Collapse - How Societies Choose to Fail or Succeed - PDF Room - Inglês (2024)

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COLLAPSEHOW S O C I E T I E S CHOOSETO FAIL OR S U C C E E D J A R E D D I A M O N DV I K I N GVIKINGPublished by the Penguin GroupPenguin Group (USA) Inc., 375 Hudson Street,New York, New York 10014, U.S.A.Penguin Group (Canada), 10 Alcorn Avenue, Toronto, Ontario, Canada M4V 3B2(a division of Pearson Penguin Canada Inc.)Penguin Books Ltd, 80 Strand, London WC2R ORL, EnglandPenguin Ireland, 25 St. Stephen's Green, Dublin 2, Ireland(a division of Penguin Books Ltd)Penguin Books Australia Ltd, 250 Camberwell Road, Camberwell, Victoria 3124, Australia(a division of Pearson Australia Group Pty Ltd)Penguin Books India Pvt Ltd, 11 Community Centre, Panchsheel Park,New Delhi—110 017, IndiaPenguin Group (NZ), Cnr Airborne and Rosedale Roads, Albany,Auckland 1310, New Zealand(a division of Pearson New Zealand Ltd)Penguin Books (South Africa) (Pty) Ltd, 24 Sturdee Avenue,Rosebank, Johannesburg 2196, South AfricaPenguin Books Ltd, Registered Offices: 80 Strand, London WC2R ORL, EnglandFirst published in 2005 by Viking Penguin, a member of Penguin Group (USA) Inc.13579 10 8642Copyright © Jared Diamond, 2005All rights reservedMaps by Jeffrey L. WardLIBRARY OF CONGRESS CATALOGING IN PUBLICATION DATADiamond, Jared M.Collapse: how societies choose to fail or succeed/Jared Diamond.p. cm.Includes index.ISBN 0-670-03337-51. Social history—Case studies. 2. Social change—Case studies. 3. Environmental policy—Case studies. I. Title.HN13. D5 2005304.2'8—dc22 2004057152This book is printed on acid-free paper. 8Printed in the United States of AmericaSet in MinionDesigned by Francesca BelangerWithout limiting the rights under copyright reserved above, no part of this publication may bereproduced, stored in or introduced into a retrieval system, or transmitted, in any form or by anymeans (electronic, mechanical, photocopying, recording or otherwise), without the prior writtenpermission of both the copyright owner and the above publisher of this book.The scanning, uploading, and distribution of this book via the Internet or via any other meanswithout the permission of the publisher is illegal and punishable by law. Please purchase onlyauthorized electronic editions and do not participate in or encourage electronic piracy ofcopyrightable materials. Your support of the author's rights is appreciated.ToJack and Ann Hirschy,Jill Hirschy Eliel and John Eliel,Joyce Hirschy McDowell,Dick (1929-2003) and Margy Hirschy,and their fellow Montanans:guardians of Montana's big skyI met a traveler from an antique land Who said:"Two vast and trunkless legs of stone Stand in thedesert. Near them, on the sand, Half sunk, ashattered visage lies, whose frown, And wrinkledlip and sneer of cold command, Tell that itssculptor well those passions read, Which yetsurvive, stampt on these lifeless things, The handthat mockt them and the heart that fed: And onthe pedestal these words appear: 'My name isOzymandias, king of kings: Look on my works,ye Mighty, and despair!' Nothing beside remains.Round the decay Of that colossal wreck,boundless and bare The lone and level sandsstretch far away.""Ozymandias," by Percy Bysshe Shelley (1817)C O N T E N T SList of Maps xiuPrologue: A Tale of Two Farms1Two farms « Collapses, past and present » Vanished Edens? Afive-point framework Businesses and the environment Thecomparative method Plan of the book PartOne: MODERN MONTANA 25Chapter 1: Under Montana's Big Sky 27Stan Falkow's story « Montana and me Why begin withMontana? Montana's economic history Mining • Forests Soil Water «» Native and non-native species Differing visions »Attitudes towards regulation • Rick Laible's story Chip Pigman'sstory » Tim Huls's story John Cook's story Montana, model ofthe world *PartTwo: PAST SOCIETIES 77Chapter 2: Twilight at Easter 79The quarry's mysteries « Easter's geography and history Peopleand food * Chiefs, clans, and commoners Platforms and statues Carving, transporting, erecting The vanished forest Consequences for society Europeans and explanations Whywas Easter fragile? Easter as metaphor •Chapter 3: The Last People Alive: Pitcairn and Henderson Islands 120Pitcairn before the Bounty Three dissimilar islands » Trade The movie's ending *Chapter 4: The Ancient Ones: The Anasazi and Their Neighbors 136Desert farmers • Tree rings * Agricultural strategies * Chaco'sproblems and packrats • Regional integration Chaco's decline andend * Chaco's message X ContentsChapter 5: The Maya Collapses 157Mysteries of lost cities The Maya environment Mayaagriculture Maya history Copan * Complexities ofcollapses Wars and droughts Collapse in the southernlowlands The Maya message Chapter 6: The Viking Prelude and Fugues 178Experiments in the Atlantic The Viking explosion Autocatalysis Viking agriculture Iron Viking chiefs Vikingreligion Orkneys, Shetlands, Faeroes Iceland's environment Iceland's history Iceland in context Vinland Chapter 7: Norse Greenland's Flowering 211Europe's outpost Greenland's climate today Climate in the past Native plants and animals « Norse settlement Farming Hunting and fishing An integrated economy Society Tradewith Europe * Self-image Chapter 8: Norse Greenland's End 248Introduction to the end Deforestation » Soil and turf damage The Inuit's predecessors Inuit subsistence Inuit/Norse relations* The end Ultimate causes of the end «Chapter 9: Opposite Paths to Success 277Bottom up, top down New Guinea highlands Tikopia Tokugawa problems Tokugawa solutions Why Japansucceeded Other successes Part Three: MODERN SOCIETIES 309Chapter 10: Malthus in Africa: Rwanda's Genocide 311A dilemma Events in Rwanda * More than ethnic hatred Buildup in Kanama Explosion in Kanama Why it happened Chapter 11: One Island, Two Peoples, Two Histories:The Dominican Republic and Haiti 329Differences * Histories Causes of divergence * Dominicanenvironmental impacts Balaguer The Dominicanenvironment today The future Contents xiChapter 12: China, Lurching Giant 358China's significance Background Air, water, soil Habitat,species, megaprojects Consequences Connections The future•Chapter 13: "Mining" Australia 378Australia's significance * Soils Water Distance Early historyE Imported values Trade and immigration Land degradation •Other environmental problems Signs of hope and change Part Four: PRACTICAL LESSONS 417Chapter 14: Why Do Some Societies Make DisastrousDecisions? 419Road map for success Failure to anticipate Failure to perceive Rational bad behavior Disastrous values Other irrationalfailures Unsuccessful solutions • Signs of hope «Chapter 15: Big Businesses and the Environment:Different Conditions, Different Outcomes 441Resource extraction « Two oil fields » Oil company motives Hardrock mining operations * Mining company motives •Differences among mining companies The logging industry «Forest Stewardship Council The seafood industry Businessesand the public »Chapter 16: The World as a Polder: What Does It All Meanto Us Today? 486Introduction The most serious problems • If we don't solve them... Life in Los Angeles • One-liner objections The past and thepresent Reasons for hope Acknowledgments 526Further Readings 529Index ' 561Illustration Credits 576LIST OF MAPSThe World: Prehistoric, Historic, and Modern Societies 4-5Contemporary Montana 31The Pacific Ocean, the Pitcairn Islands, and Easter Island 84-85The Pitcairn Islands 122Anasazi Sites 142Maya Sites 161The Viking Expansion 182-183Contemporary Hispaniola 331Contemporary China 361Contemporary Australia 386Political Trouble Spots of the Modern World;Environmental Trouble Spots of the Modern World 497IC O L L A P S EP R O L O G U EA Tale of Two FarmsTwo farms Collapses, pastreconnection, mywife and sons and I have been visiting Montana every year—drawn to it ul-timately by the same unforgettable beauty of its big sky that drew or keptmy other friends there (Plates 1-3).That big sky grew on me. After living for so many years elsewhere, Ifound that it took me several visits to Montana to get used to the panoramaof the sky above, the mountain ring around, and the valley floor below—toappreciate that I really could enjoy that panorama as a daily setting for partof my life—and to discover that I could open myself up to it, pull myselfaway from it, and still know that I could return to it. Los Angeles has its ownpractical advantages for me and my family as a year-round base of work,school, and residence, but Montana is infinitely more beautiful and (as StanFalkow said) peaceful. To me, the most beautiful view in the world is theview down to the Big Hole's meadows and up to the snowcapped peaks ofthe Continental Divide, as seen from the porch of Jill and John Eliel's ranchhouse.Montana in general, and the Bitterroot Valley in its southwest, are a land ofparadoxes. Among the lower 48 states, Montana is the third largest in area,yet the sixth smallest in population, hence the second lowest in populationdensity. Today the Bitterroot Valley looks lush, belying its original naturalvegetation of just sagebrush. Ravalli County in which the valley is located isso beautiful and attracts so many immigrants from elsewhere in the U.S.(including even from elsewhere in Montana) that it is one of our nation'sfastest growing counties, yet 70% of its own high school graduates leave thevalley, and most of those leave Montana. Although population is increasingin the Bitterroot, it is falling in eastern Montana, so that for the state ofMontana as a whole the population trend is flat. Within the past decade thenumber of Ravalli County residents in their 50s has increased steeply, butthe number in their 30s has actually decreased. Some of the people recentlyestablishing homes in the valley are extremely wealthy, such as the broker-age house founder Charles Schwab and the Intel president Craig Barrett,but Ravalli County is nevertheless one of the poorest counties in the state ofMontana, which in turn is nearly the poorest state in the U.S. Many of thecounty's residents find that they have to hold two or three jobs even to earnan income at U.S. poverty levels.We associate Montana with natural beauty. Indeed, environmentallyMontana is perhaps the least damaged of the lower 48 states; ultimately,that's the main reason why so many people are moving to Ravalli County.The federal government owns over one-quarter of the land in the state andthree-quarters of the land in the county, mostly under the title of nationalforest. Nevertheless, the Bitterroot Valley presents a microcosm of the envi-ronmental problems plaguing the rest of the United States: increasingpopulation, immigration, increasing scarcity and decreasing quality of wa-ter, locally and seasonally poor air quality, toxic wastes, heightened risksfrom wildfires, forest deterioration, losses of soil or of its nutrients, losses ofbiodiversity, damage from introduced pest species, and effects of climatechange.Montana provides an ideal case study with which to begin this book onpast and present environmental problems. In the case of the past societiesthat I shall discuss—Polynesian, Anasazi, Maya, Greenland Norse, andothers—we know the eventual outcomes of their inhabitants' decisionsabout managing their environment, but for the most part we don't knowtheir names or personal stories, and we can only guess at the motives thatled them to act as they did. In contrast, in modern Montana we do knownames, life histories, and motives. Some of the people involved have beenmy friends for over 50 years. From understanding Montanans' motives, wecan better imagine motives operating in the past. This chapter will put apersonal face on a subject that could otherwise seem abstract.In addition, Montana provides a salutory balance to the following chap-ters' discussions of small, poor, peripheral, past societies in fragile environ-ments. I intentionally chose to discuss those societies because they were theones suffering the biggest consequences of their environmental damage,and they thus powerfully illustrate the processes that form the subject ofthis book. But they are not the only types of societies exposed to serious en-vironmental problems, as illustrated by the contrast case of Montana. It ispart of the richest country in the modern world, and it is one of the mostpristine and least populated parts of that country, seemingly with fewerproblems of environment and population than the rest of the U.S. Cer-tainly, Montana's problems are far less acute than those of crowding, traffic,smog, water quality and quantity, and toxic wastes that beset Americans inLos Angeles, where I live, and in the other urban areas where most Ameri-cans live. If, despite that, even Montana has environmental and populationproblems, it becomes easier to understand how much more serious thoseproblems are elsewhere in the U.S. Montana will illustrate the five mainthemes of this book: human impacts on the environment; climate change; asociety's relations with neighboring friendly societies (in the case of Mon-tana, those in other U.S. states); a society's exposure to acts of other poten-tially hostile societies (such as overseas terrorists and oil producers today);and the importance of a society's responses to its problems.The same environmental disadvantages that penalize food productionthroughout the whole of the American Intermontane West also limit Mon-tana's suitability for growing crops and raising livestock. They are: Mon-tana's relatively low rainfall, resulting in low rates of plant growth; its highlatitude and high altitude, both resulting in a short growing season and lim-iting crops to one a year rather than the two a year possible in areas with alonger summer; and its distance from markets in the more densely popu-lated areas of the U.S. that might buy its products. What those disadvan-tages mean is that anything grown in Montana can be grown more cheaplyand with higher productivity, and transported faster and more cheaply topopulation centers, elsewhere in North America. Hence Montana's historyconsists of attempts to answer the fundamental question of how to make aliving in this beautiful but agriculturally non-competitive land.Human occupation of Montana falls into several economic phases. Thefirst phase was of Native Americans, who arrived at least 13,000 years ago.In contrast to the agricultural societies that they developed in eastern andsouthern North America, Montana's Native Americans before European ar-rival remained hunter-gatherers, even in areas where agriculture and herd-ing are practiced today. One reason is that Montana lacked native wild plantand animal species lending themselves to domestication, so there were noindependent origins of agriculture in Montana, in contrast to the situationin eastern North America and Mexico. Another reason is that Montana layfar from those two Native American centers of independent agriculturalorigins, so that crops originating there had not spread to Montana by thetime of European arrival. Today, about three-quarters of Montana's remain-ing Native Americans live on seven reservations, most of which are poor innatural resources except for pasture.The first recorded Europeans to visit Montana were the members of thetranscontinental Lewis and Clark Expedition of 1804-1806, which spentmore time in what was later to become Montana than in any other state.They were followed by Montana's second economic phase involving themountain men," fur trappers and traders coming down from Canada andalso from the U.S. The next phase began in the 1860s and was based onthree foundations of Montana's economy that havecontinued (albeit withdiminishing importance) until the present: mining, especially of copperand gold; logging; and food production, involving raising cattle and sheepand growing grains, fruits, and vegetables. The influx of miners to Mon-tana's big copper mine at Butte stimulated other sectors of the economy tomeet the needs of that internal market within the state. In particular, muchtimber was taken out of the nearby Bitterroot Valley to provide power forthe mines, to construct miners' houses, and to shore up the mine shafts; andmuch food for the miners was grown in the valley, whose southerly locationand mild climate (by Montana standards) give it the nickname of "Mon-tana's Banana Belt." Although the valley's rainfall is low (13 inches per year)and the natural vegetation is sagebrush, the first European settlers in the1860s already began overcoming that disadvantage by building small irriga-tion ditches fed by streams draining the Bitterroot Mountains on the valley'swest side; and later, by engineering two sets of large-scale and expensive irri-gation systems, one (the so-called Big Ditch) built in 1908-1910 to take wa-ter from Lake Como on the west side of the valley, and the other consistingof several large irrigation canals drawing water from the Bitterroot River it-self. Among other things, irrigation permitted a boom in apple orchardsthat began in the Bitterroot Valley in the 1880s and peaked in the early de-cades of the 20th century, but today few of those orchards remain in com-mercial operation.Of those former bases of Montana's economy, hunting and fishing haveshifted from a subsistence activity to a recreation; the fur trade is extinct;and mines, logging, and agriculture are declining in importance, because ofeconomic and environmental factors to be discussed below. Instead, the sec-tors of the economy that are growing nowadays are tourism, recreation, re-tirement living, and health care. A symbolic landmark in the BitterrootValley's recent economic transformation took place in 1996, when a 2,600-acre farm called the Bitterroot Stock Farm, formerly the estate of the Mon-tana copper baron Marcus Daly, was acquired by the wealthy brokeragehouse owner Charles Schwab. He began to develop Daly's estate for veryrich out-of-staters who wanted a second (or even a third or fourth) home inthe beautiful valley to visit for fishing, hunting, horseback riding, and golf-ing a couple of times each year. The Stock Farm includes an 18-hole cham-pionship golf course and about 125 sites for what are called either houses orcabins, "cabin" being a euphemism for a structure of up to six bedroomsand 6,000 square feet selling for $800,000 or more. Buyers of Stock Farmlots must be able to prove that they meet high standards of net worth andincome, the least of which is the ability to afford a club membership initia-tion fee of $125,000, which is more than seven times the average annual in-come of Ravalli County residents. The whole Stock Farm is fenced, and theentrance gate bears a sign, MEMBERS AND GUESTS ONLY. Many of the ownersarrive by private jet and rarely shop or set foot in Hamilton, but prefer to eat atthe Stock Farm club or else have their groceries picked up from Hamilton byclub employees. As one local Hamilton resident explained to me bitterly, "Youcan spot coveys of the aristocracy when they decide to go slumming downtownin tight packs like foreign tourists."The announcement of the Stock Farm's development plan came as a shock tosome Bitterroot Valley long-timers, who predicted that no one would pay somuch money for valley land, and that the lots would never sell. As it turned out,the long-timers were wrong. While rich out-of-staters had already been visitingand buying in the valley as individuals, the Stock Farm's opening was asymbolic milestone because it involved so many very rich people buyingBitterroot land at once. Above all, the Stock Farm drove home how much morevaluable the valley's land had become for recreation than for its traditional usesof growing cows and apples.Montana's environmental problems today include almost all of the dozen typesof problems that have undermined pre-industrial societies in the past, or thatnow threaten societies elsewhere in the world as well. Particularly conspicuousin Montana are problems of toxic wastes, forests, soils, water (and sometimesair), climate change, biodiversity losses, and introduced pests. Let's begin withseemingly the most transparent problem, that of toxic wastes.While concern is mounting in Montana about runoff of fertilizer, manure,septic tank contents, and herbicides, by far the biggest toxic waste issue is posedby residues from metal mining, some of it from the last century and some of itrecent or ongoing. Metal mining—especially of copper, but also of lead,molybdenum, palladium, platinum, zinc, gold, and silver— stood as one of thetraditional pillars of Montana's economy. No one disagrees that mining isessential, somewhere and somehow: modern civilization and its chemical,construction, electric, and electronic industries run on metals. Instead, thequestion is where and how best to mine metal-bearing ores.Unfortunately, the ore concentrate that is eventually carried away from aMontana mine in order to extract the metals represents only a fraction of theearth that must first be dug up. The remainder is waste rock and tailings stillcontaining copper, arsenic, cadmium, and zinc, which are toxic to people(as well as to fish, wildlife, and our livestock) and hence are bad news whenthey get into groundwater, rivers, and soil. In addition, Montana ores arerich in iron sulfide, which yields sulfuric acid. In Montana there are about20,000 abandoned mines, some of them recent but many of them a centuryor more old, that will be leaking acid and those toxic metals essentially for-ever. The vast majority of those mines have no surviving owners to bear fi-nancial responsibility, or else the known owners aren't rich enough toreclaim the mine and treat its acid drainage in perpetuity.Toxicity problems associated with mining were already recognized atButte's giant copper mine and nearby smelter a century ago, when neigh-boring ranchers saw their cows dying and sued the mine's owner, AnacondaCopper Mining Company. Anaconda denied responsibility and won the re-sulting lawsuit, but in 1907 it nevertheless built the first of several settlingponds to contain the toxic wastes. Thus, we have known for a long time thatmine wastes can be sequestered so as to minimize problems; some newmines around the world now do so with state-of-the-art technology, whileothers continue to ignore the problem. In the U.S. today, a company open-ing a new mine is required by law to buy a bond by which a separate bond-holding company pledges to pay for the mine's cleanup costs in case themining company itself goes bankrupt. But many mines have been "under-bonded" (i.e., the eventual cleanup costs have proved to exceed the value ofthe bond), and older mines were not required to buy such bonds at all.In Montana as elsewhere, companies that have acquired older mines re-spond to demands to pay for cleanup in either of two ways. Especially if thecompany is small, its owners may declare the company bankrupt, in somecases conceal its assets, and transfer their business efforts to other compa-nies or to new companies that do not bear responsibility for cleanup at theold mine. If the company is so large that it cannot claim that it would bebankrupted by cleanup costs (as in the case of ARCO that I shall discuss be-low), the company instead denies its responsibility or else seeks to minimizethe costs. In either case, either the mine site and areas downstream of it re-main toxic, thereby endangering people, or else the U.S. federal governmentand the Montana state government (hence ultimately all taxpayers) pay forthe cleanup through the federal Superfund and a correspondingMontanastate fund.These two alternative responses by mining companies pose a questionthat will recur throughout this book, as we try to understand why any per-son or group in any society would knowingly do something harmful to thesociety as a whole. While denial or minimization of responsibility may be inthe short-term financial interests of the mining company, it is bad for soci-ety as a whole, and it may also be bad for the long-term interests of thecompany itself, or of the entire mining industry. Despite Montanans' long-standing embrace of mining as a traditional value defining their state'sidentity, they have recently become increasingly disillusioned with miningand have contributed to the industry's near-demise within Montana. Forinstance, in 1998, to the shock of the industry, and to politicians supportingand supported by the industry, Montana voters passed a ballot initiativebanning a problem-plagued method of gold mining termed cyanide heap-leach mining and discussed further below. Some of my Montana friendsnow say: in retrospect, when we compare the multi-billion-dollar minecleanup costs borne by us taxpayers with Montana's own meager past earn-ings from its mines, most of whose profits went to shareholders in the east-ern U.S. or in Europe, we realize that Montana would have been better off inthe long run if it had never mined copper at all but had just imported itfrom Chile, leaving the resulting problems to the Chileans!It is easy for us non-miners to become indignant at mining companiesand to view their behavior as morally culpable. Didn't they knowingly dothings that harmed us, and aren't they now shirking their responsibility? Asign posted over the toilet of one Montanan friend of mine reads, "Do notflush. Be like the mining industry and let someone else clean up yourwaste!"In fact, the moral issue is more complex. Here is one explanation that Iquote from a recent book: "... ASARCO [American Smelting and RefiningCompany, a giant mining and smelting company] can hardly be blamed[for not cleaning up an especially toxic mine that it owned]. American busi-nesses exist to make money for their owners; it is the modus operandi ofAmerican capitalism. A corollary to the money-making process is notspending it needlessly... Such a tight-fisted philosophy is not limited to themining industry. Successful businesses differentiate between those expensesnecessary to stay in business and those more pensively characterized asmoral obligations.' Difficulties or reluctance to understand and accept thisdistinction underscores much of the tension between advocates of broadlymandated environmental programs and the business community. Businessleaders are more likely to be accountants or attorneys than members of theclergy." That explanation does not come from the CEO of ASARCO, butfrom environmental consultant David Stiller, who sought in his bookWounding the West: Montana, Mining, and the Environment to understandhow Montana's toxic mine waste problem arose, and what society really hasto do to fix it.It's a cruel fact that no simple cheap way exists to clean up old mines.Early miners behaved as they did because the government required almostnothing of them, and because they were businessmen operating accordingto the principles that David Stiller explained. Not until 1971 did the state ofMontana pass a law requiring mining companies to clean up their propertywhen their mine closed. Even rich companies (like ARCO and ASARCO)that may be inclined to clean up become reluctant to do so when they real-ize that they may then be asked to do the impossible, or that the costs will beexcessive, or that the achievable results will be less than the public expected.When the mine owner can't or won't pay, taxpayers don't want to step inand pay billions of dollars of cleanup costs either. Instead, taxpayers feelthat the problem has existed for a long time, out of sight and out of theirbackyards, so it must be tolerable; most taxpayers balk at spending money ifthere isn't an immediate crisis; and not enough taxpayers complain abouttoxic wastes or support high taxes. In this sense, the American public is asresponsible for inaction as are miners and the government; we the publicbear the ultimate responsibility. Only when the public pressures its politi-cians into passing laws demanding different behavior from mining compa-nies will the companies behave differently: otherwise, the companies wouldbe operating as charities and would be violating their responsibility to theirshareholders. Three cases will serve to illustrate some of the various out-comes of these dilemmas to date: the cases of the Clark Fork, MilltownDam, and Pegasus Zortman-Landusky Mine.In 1882 the mining companies that later became the Anaconda CopperMining Company began operations at Butte near the headwaters of theClark Fork of the Columbia River. By 1900, Butte accounted for half of theU.S.'s copper output. Until 1955 most mining at Butte involved under-ground tunnels, but in 1955 Anaconda began excavating an open-pit minecalled the Berkeley Pit, now an enormous hole over a mile in diameter and1,800 feet deep. Huge quantities of acidic mine tailings with toxic metalsended up in the Clark Fork River. But Anaconda's fortunes then declinedbecause of cheaper foreign competition, expropriation of its mines in Chile,and growing environmental concerns in the U.S. In 1976 Anaconda wasbought by the big oil company ARCO (more recently bought in turn by thebigger oil company BP), which closed the smelter in 1980 and the mine it-self in 1983, thereby eliminating thousands of jobs and three-quarters ofthe economic base for the Butte area.The Clark Fork River, including the Berkeley Pit, is now the largest andmost expensive Superfund cleanup site in the U.S. In ARCO's view, it is un-fair to hold ARCO responsible for damage done by the mine's previousowner, before the Superfund law even existed. In the view of the federal andstate governments, ARCO acquired Anaconda's assets, including Anaconda'sliabilities. At least, ARCO and BP are not declaring bankruptcy. As one envi-ronmentalist friend told me, "They are trying to get away with paying as lit-tle as possible, but there are worse companies to deal with than ARCO." Theacidic water seeping into the Berkeley Pit will be pumped out and treatedforever. ARCO has already paid several hundred million dollars to the stateof Montana for restoration of the Clark Fork, and its total eventual liabilityis estimated at one billion dollars, but that estimate is uncertain becausethe cleanup treatment consumes much power: who knows what power willcost 40 years from now?The second case involves Milltown Dam, built in 1907 across the ClarkFork River downstream of Butte to generate power for a nearby sawmill.Since then, 6,600,000 cubic yards of sediments contaminated with arsenic,cadmium, copper, lead, and zinc have been washed down from Butte'smines and accumulated in the reservoir behind the dam. A resulting "mi-nor" problem is that the dam prevents fish from migrating along the ClarkFork and Blackfoot Rivers (the latter is the trout stream made famous byNorman Maclean's novella and Robert Redford's film A River Runs ThroughIt). The major problem, discovered in 1981 when local people noticed a badtaste in drinking water from their wells, is that a huge plume of ground-water with dangerous arsenic levels 42 times higher than federal water stan-dards is spreading from the reservoir. The dam is decrepit, in need of repair,poorly anchored, located in an earthquake zone, was nearly broken by anice jam in 1996, and is expected to break sooner or later. No one wouldthink of constructing such a flimsy dam today. If the dam did break and re-lease its toxic sediments, the water supply of Missoula, southwestern Mon-tana's largest city located just seven miles downstream of the dam, wouldbecome undrinkable, and the lowerClark Fork River would be ruined forfishing.ARCO acquired the liability for the toxic sediments behind the damwhen it bought Anaconda Copper Mining Company, whose activities cre-ated the sediments. The near-disaster in the ice jam of 1996, and fish deathsdownstream resulting from releases of water with toxic copper levels fromthe dam then and again in 1998, triggered recognition that something hadto be done about the dam. Federal and state scientists recommended re-moving it and its accumulated toxic sediments, at a cost to ARCO of about$100,000,000. For a long time, ARCO denied that the toxic sediments causedthe fish deaths, denied its liability for the arsenic in Milltown groundwateror for cancer in the Milltown area, funded a "grass-roots" movement in thenearby town of Bonner to oppose removing the dam, and proposed insteadjust strengthening it, at the much lower cost of $20,000,000. But Missoulapoliticians, businesspeople, and the public, who initially considered theproposal to remove the dam crazy, switched to being strongly in favor of it.In 2003 the federal Environmental Protection Agency adopted the proposal,making it almost certain that the dam will be removed.The remaining case is that of the Zortman-Landusky Mine owned byPegasus Gold, a small company founded by people from other mining com-panies. That mine employed a method known as cyanide heap-leaching, de-veloped for extracting very low-grade gold ores requiring 50 tons of ores toyield one ounce of gold. The ore is excavated from an open pit, piled in abig heap (approximating a small mountain) inside a lined leach pad, andsprayed with a solution of cyanide, best known as the poison used to gener-ate the hydrogen cyanide gas used both in Nazi gas chambers and in Ameri-can prison gas chambers, but with the virtue of binding to gold. Hence asthe cyanide-containing solution seeps through the ore heap, it picks up thegold and is drained off to a nearby pond, whence it is pumped to a process-ing plant for extracting the gold. The leftover cyanide solution containingtoxic metals is disposed of by spraying it on nearby forests or rangeland, orelse is enriched with more cyanide and sprayed back on the heap.Obviously, in this heap-leach process several things can go wrong, all ofwhich did go wrong at the Zortman-Landusky Mine (Plate 4). The leach pad'sliner is as thin as a nickel and inevitably develops leaks under the weightof millions of tons of ore being pushed around by heavy machinery. Thepond with its noxious brew may overflow; that happened at the Zortman-Landusky Mine during a rainstorm. Finally, the cyanide itself is dangerous:in a flooding emergency at the mine, when the owners received permissionto dispose of excess solution by spraying it nearby to prevent the pads frombursting, mishandling of the spraying operation led to the formation ofcyanide gas that nearly killed some of the workers. Pegasus Gold eventuallydeclared bankruptcy, abandoning its huge open pits, heaps, and ponds fromwhich acid and cyanide will leak out forever. Pegasus' bond proved insuffi-cient to cover the cleanup cost, leaving taxpayers to pay the remaining bills,estimated at $40,000,000 or more. These three case studies of toxic minewaste problems that I have described, and thousands of others, illustratewhy visitors from Germany, South Africa, Mongolia, and other countriescontemplating mining investments have recently been coming to Montanato inform themselves at first hand about bad mining practices and theirconsequences.A second set of environmental problems in Montana involves the loggingand burning of its forests. Just as no one denies that metal mining is essen-tial, somewhere and somehow, no one would dispute that logging is alsonecessary to obtain wood for timber and for making paper. The questionthat my Montana friends sympathetic to logging raise is: if you object tologging in Montana, where do you propose to get wood instead? Rick Laibledefended to me a controversial recent Montana logging proposal by noting,"It beats cutting down the rainforest!" Jack Ward Thomas's defense wassimilar: "By refusing to harvest our own dead trees and instead importinglive trees from Canada, we have exported both the environmental effects oflogging, and the economic benefits of it, to Canada." Dick Hirschy sarcasti-cally commented, "There's a saying, 'Don't rape the land by logging'—so weare raping Canada instead."Commercial logging began in the Bitterroot Valley in 1886, to providePonderosa Pine logs for the mining community at Butte. The post-WorldWar II housing boom in the U.S., and the resulting surge in demand forwood, caused timber sales on U.S. National Forest land to peak around 1972at over six times their 1945 levels. DDT was released over forests from air-planes to control insect tree pests. In order to be able to reestablish uniformeven-aged trees of chosen tree species, and thereby to maximize timberyields and increase logging efficiency, logging was carried out by clear-cutting all trees rather than by selective logging of marked individual trees.Set against those big advantages of clear-cutting were some disadvantages:water temperatures in streams no longer shaded by trees rose above valuesoptimal for fish spawning and survival; snow on unshaded bare groundmelted in a quick pulse in the spring, instead of the shaded forest's snow-pack gradually melting and releasing water for irrigating ranches through-out the summer; and, in some cases, sediment runoff increased, and waterquality decreased. But the most visible evil of clear-cutting, for citizens of astate who considered their land's most valuable resource to be its beauty,was that clear-cut hillsides looked ugly, really ugly.The resulting debate became known as the Clearcut Controversy. Out-raged Montana ranchers, landowners, and the general public protested. U.S.Forest Service managers made the mistake of insisting that they were theprofessionals who knew all about logging, and that the public was ignorantand should keep quiet. The 1970 Bolle Report, prepared by forestry profes-sionals outside the Forest Service, criticized Forest Service policies and,fanned by similar disputes over clear-cutting of West Virginia nationalforests, led to national changes, including restrictions on clear-cutting and areturn to emphasis on managing forests for multiple purposes other thantimber production (as already envisioned when the Forest Service was es-tablished in 1905).In the decades since the Clearcut Controversy, Forest Service annualtimber sales have decreased by more than 80%—in part because of environ-mental regulations mandated in the Endangered Species Act, the Clean Wa-ter Act, and requirements for national forests to maintain habitats for allspecies, and in part because of the decline in easily accessible big trees dueto logging itself. When the Forest Service now proposes a timber sale, envi-ronmental organizations file protests and appeals that take up to 10 years toresolve and that make logging less economic even if the appeals are ulti-mately denied. Virtually all my Montana friends, even those who considerthemselves dedicated environmentalists, told me that they consider the pen-dulum to have swung too far in the direction away from logging. They feelfrustrated that logging proposals appearing well justified to them (such asfor the purpose of reducing the forest fire fuel loads discussed below) en-counter long delays in the courts. But the environmental organizations fil-ing the protests have concluded that they should suspect the usual disguisedpro-logging agenda behind any seemingly reasonable government proposalinvolving logging. All of the Bitterroot Valley's former timber mills havenow closed, because so little timber is available from Montana publiclyowned timberland, and because the valley's privately owned timberland hasalready been logged twice. The mills' closinghas meant the loss of manyhigh-paying unionized jobs, as well as of traditional Montanan self-image.Elsewhere in Montana, outside the Bitterroot Valley, much private tim-berland remains, most of it originating from government land grants madein the 1860s to the Great Northern Railroad as an inducement for buildinga transcontinental railroad. In 1989 that land was spun off from the rail-roads to a Seattle-based entity called Plum Creek Timber Company, orga-nized for tax purposes as a real estate investment trust (so that its earningswill be taxed at lower rates as capital gains), and now the largest owner ofprivate timberland in Montana and the second-largest one in the U.S. I'veread Plum Creek's publications and talked with their director of corporateaffairs, Bob Jirsa, who defends Plum Creek's environmental policies andsustainable forestry practices. I've also heard numerous Montana friendsvent unfavorable opinions about Plum Creek. Typical of their complaintsare the following: "Plum Creek cares only about the bottom line"; "they arenot interested in sustainable forestry"; "they have a corporate culture, andtheir goal is 'Get out more logs!' "; "Plum Creek earns money in whateverway it can from the land"; "they do weed control only if someonecomplains."Should these polarized views remind you of the views that I alreadyquoted about mining companies, you're right. Plum Creek is organized as aprofit-making business, not as a charity. If Montana citizens want PlumCreek to do things that would diminish its profits, it's their responsibility toget their politicians to pass and enforce laws demanding those things, or tobuy out the lands and manage them differently. Looming over this disputeis a basic hard fact: Montana's cold dry climate and high elevation placemost of its land at a relative disadvantage for forestry. Trees grow severaltimes faster in the U.S. Southeast and Northeast than in Montana. WhilePlum Creek's largest land holdings are in Montana, four other states (Ar-kansas, Georgia, Maine, and Mississippi) each produce more timber forPlum Creek on only 60 to 64% of its Montana acreage. Plum Creek cannotget a high rate of return from its Montana logging operations: it has to paytaxes and fire protection on the land while sitting on it for 60 to 80 years be-fore harvesting trees, whereas trees reach a harvestable size in 30 years on itssoutheastern U.S. lands. When Plum Creek faces economic realities and seesmore value in developing its Montana lands, especially those along riversand lakes, for real estate than for timber, that's because prospective buyerswho seek beautiful waterfront property hold the same opinion. Those buy-ers are often representatives of conservation interests, including the govern-ment. For all these reasons, the future of logging in Montana even morethan elsewhere in the U.S. is uncertain, as is that of mining.Related to these issues of forest logging are issues of forest fires, whichhave recently increased in intensity and extent in some forest types in Mon-tana and throughout the western U.S., with the summers of 1988, 1996,2000, 2002, and 2003 being especially severe fire years. In the summer of2000, one-fifth of the Bitterroot Valley's remaining area of forest burned.Whenever I fly back to the Bitterroot nowadays, my first thought on lookingout my airplane's window is to count the number of fires or to gauge theamount of smoke on this particular day. (On August 19, 2003, as I was fly-ing to Missoula airport, I counted a dozen fires whose smoke reduced visi-bility to a few miles.) Each time that John Cook took my sons out fly-fishingin 2000, his choice of which stream to fish depended partly on where thefires were burning that day. Some of my friends in the Bitterroot have hadto be evacuated repeatedly from their homes because of approaching fires.This recent increase in fires has resulted partly from climate change (therecent trend towards hot dry summers) and partly from human activities,for complicated reasons that foresters came increasingly to understandabout 30 years ago but whose relative importance is still debated. One factoris the direct effects of logging, which often turns a forest into something ap-proximating a huge pile of kindling: the ground in a logged forest may re-main covered with lopped-off branches and treetops, left behind when thevaluable trunks are carted away; a dense growth of new vegetation springsup, further increasing the forest's fuel loads; and the trees logged and re-moved are of course the biggest and most fire-resistant individuals, leavingbehind smaller and more flammable trees. Another factor is that the U.S.Forest Service in the first decade of the 1900s adopted a policy of fire sup-pression (attempting to put out forest fires) for the obvious reasons that itdidn't want valuable timber to go up in smoke, nor people's homes and livesto be threatened. The Forest Service's announced goal became, "Put outevery forest fire by 10:00 A.M. on the morning after the day when it is firstreported." Firefighters became much more successful at achieving that goalafter World War II, thanks to the availability of firefighting planes, an ex-panded road system for sending in fire trucks, and improved firefightingtechnology. For a few decades after World War II, the annual acreage burntdecreased by 80%.That happy situation began to change in the 1980s, due to the increasingfrequency of large forest fires that were essentially impossible to extinguishunless rain and low winds combined to help. People began to realize thatthe U.S. federal government's fire suppression policy was contributing tothose big fires, and that natural fires caused by lightning had previouslyplayed an important role in maintaining forest structure. That natural roleof fire varies with altitude, tree species, and forest type. To take the Bitter-root's low-altitude Ponderosa Pine forest as an example, historical records,plus counts of annual tree rings and datable fire scars on tree stumps,demonstrated that a Ponderosa Pine forest experiences a lightning-lit fireabout once a decade under natural conditions (i.e., before fire suppressionbegan around 1910 and became effective after 1945). The mature Ponderosatrees have bark two inches thick and are relatively resistant to fire, which in-stead burns out the understory of fire-sensitive Douglas Fir seedlings thathave grown up since the last fire. But after only a decade's growth until thenext fire, those seedlings are still too low for fire to spread from them intothe crowns. Hence the fire remains confined to the ground and understory.As a result, many natural Ponderosa Pine forests have a park-like appear-ance, with low fuel loads, big trees well spaced apart, and a relatively clearunderstory.Of course, though, loggers concentrated on removing those big, old,valuable, fire-resistant Ponderosa Pines, while fire suppression for decadeslet the understory fill up with Douglas Fir saplings that would in turn be-come valuable when full-grown. Tree densities increased from 30 to 200trees per acre, the forest's fuel load increased by a factor of 6, and Congressrepeatedly failed to appropriate money to thin out the saplings. Anotherhuman-related factor, sheep grazing in national forests, may also haveplayed a major role by reducing understory grasses that would otherwisehave fueled frequent low-intensity fires. When a fire finally does start in asapling-choked forest, whether due to lightning or human carelessness or(regrettably often) intentional arson, the dense tall saplings may become aladder that allows the fire to jump into the crowns. The outcome is some-times an unstoppable inferno in which flames shoot 400 feet into the air,leap from crown to crown across wide gaps, reach temperatures of 2,000 de-grees Fahrenheit, kill the tree seed bank in the soil, and may be followed bymudslides and mass erosion.Forestersnow identify the biggest problem in managing western forestsas what to do with those increased fuel loads that built up during the previ-ous half-century of effective fire suppression. In the wetter eastern U.S.,dead trees rot away more quickly than in the drier West, where more deadtrees persist like giant matchsticks. In an ideal world, the Forest Servicewould manage and restore the forests, thin them out, and remove the denseunderstory by cutting or by controlled small fires. But that would cost overa thousand dollars per acre for the one hundred million acres of western U.S.forests, or a total of about $100 billion. No politician or voter wants to spendthat kind of money. Even if the cost were lower, much of the public wouldbe suspicious of such a proposal as just an excuse for resuming logging oftheir beautiful forest. Instead of a regular program of expenditures for main-taining our western forests in a less fire-susceptible condition, the federalgovernment tolerates flammable forests and is forced to spend money un-predictably whenever a firefighting emergency arises: e.g., about $1.6 billionto fight the summer 2000 forest fires that burned 10,000 square miles.Montanans themselves hold diverse and often self-contradictory viewsabout forest management and forest fires. On the one hand, the public fearsand instinctively dislikes the "let it burn" response that the Forest Service isforced to take towards huge fires that would be dangerous or impossible totry to extinguish. When the 1988 fires in much of Yellowstone National Parkwere allowed to burn, the public was especially loud in its protests, not un-derstanding that in fact there was nothing that could be done except to prayfor rain or snow. On the other hand, the public also dislikes proposals forforest thinning programs that could make the forests less flammable, be-cause people prefer beautiful views of dense forests, they object to "unnatu-ral" interference with nature, they want to leave the forest in a "natural"condition, and they certainly don't want to pay for thinning by increasedtaxes. They (like most foresters until recently) fail to understand that west-ern forests are already in a highly unnatural condition, as the result of a cen-tury of fire suppression, logging, and sheep grazing.Within the Bitterroot, people build trophy homes next to or surroundedby flammable forests at the urban/wildland interface and then expect thegovernment to protect those homes against fires. In July 2001, when mywife and I went for a hike west of the town of Hamilton through what hadbeen the Blodgett forest, we found ourselves in a landscape of fire-charreddead trees killed in one of the big forest fires whose smoke had filled the val-ley during our summer 2000 visit. Blodgett-area residents who had previ-ously blocked Forest Service proposals to thin the forest demanded thenthat the Service hire 12 big firefighting helicopters at a cost of $2,000 perhour to save their homes by dropping water on them, while the Forest Ser-vice, obeying a government-imposed mandate to protect lives, people'sproperty, and then the forest in that order, was simultaneously allowing ex-panses of public timberlands far more valuable than those homes to burn.The Forest Service subsequently announced that it will no longer spend somuch money and endanger firefighters' lives just to protect private prop-erty. Many homeowners sue the Forest Service if their house burns in a for-est fire, or if it burns in a backfire lit by the Forest Service to control a muchbigger fire, or if it doesn't burn but if a forest providing a pretty view fromthe deck of their house does burn. Yet some Montana homeowners are af-flicted with such a rabidly anti-government attitude that they don't want topay taxes towards the costs of firefighting, nor to allow government employ-ees onto their land to carry out fire prevention measures.The next set of environmental problems in Montana involves its soils. One"minor" and specific soil problem is that the Bitterroot Valley's boom incommercial apple orchards, which were initially very profitable, collapsed,due in part to apple trees exhausting the soil's nitrogen. A more widespreadsoil problem is erosion, resulting from any of several changes that removethe plant cover normally protecting the soil: overgrazing, noxious weed in-festation, logging, or excessively hot forest fires that sterilize the topsoil.Long-timer ranching families know better than to overgraze their pastures:as Dick and Jack Hirschy expressed it to me, "We must take good care of ourland, or we will be ruined." However, one of the Hirschys' neighbors is anoutsider who paid more for his property than it could sustainably supportby ranching, and who is now overstocking his pastures in the short-sightedhope of recouping his investment. Other neighbors made the mistake ofrenting grazing rights on their land to tenants, who overgrazed for a quickprofit during their three-year lease and didn't care about the resulting long-term damage. The net result of these various causes of soil erosion is thatabout one-third of the Bitterroot's watersheds are considered to be in goodshape and not eroded, one-third are at risk of erosion, and one-third are al-ready eroded and in need of restoration.The remaining soil problem in Montana, besides nitrogen exhaustionand erosion, is salinization, a process involving salt accumulation in soil andgroundwater. While such accumulation has always occurred naturally insome areas, a more recent concern is the ruining of large areas of farmlandby salinization resulting from some human agricultural practices that I'llexplain in the next few paragraphs and in Chapter 13—particularly fromclearing of natural vegetation, and from irrigation. In parts of Montana, saltconcentrations in soil water have reached levels double those of seawater.Besides certain salts having specific toxic effects on crops, high salt con-centrations exert a general harmful effect on crops similar to the effect of adrought, by raising the osmotic pressure of soil water and thereby making itharder for roots to absorb water by osmosis. The salty groundwater mayalso end up in wells and streams and may evaporate on the surface to leave acaked layer of salt. If you imagine yourself drinking a glass of "water" moreconcentrated than the ocean, you will appreciate that not only does it tastehorrible and prevent farmers from growing crops, but that its dissolvedboron, selenium, and other toxic ingredients may be bad for your health(and for that of wildlife and your livestock). Salinization is a problem todayin many parts of the world besides the U.S., including India, Turkey, and es-pecially Australia (see Chapter 13). In the past it contributed to the declineof the world's oldest civilizations, those of Mesopotamia: salinization pro-vides a large part of the explanation for why applying the term "FertileCrescent" today to Iraq and Syria, formerly the leading center of world agri-culture, would be a cruel joke.Montana's main form of salinization is one that has ruined several mil-lion acres of cropland in the northern Great Plains as a whole, includingseveral hundred thousand acres in northern, eastern, and central Montana.The form is called "saline seep," because salty water building up in theground in an uphill area percolates through the soil to emerge as a seep in adownhill area up to half a mile or farther distant. Saline seeps frequently be-come bad for neighborly friendship when the agricultural practices of onefarmer uphill cause a saline seep on a downhill neighbor's property.Here is how a saline seep arises. Eastern Montana has lots of water-soluble salts (especially sodium, calcium, and magnesium sulfates) presentas components of the rocks and soils themselves, and also trapped in ma-rine deposits (because much of the region used to be ocean). Below the soilzone is a layerof bedrock (shale, sandstone, or coal) that has low perme-ability to water. In dry eastern Montana environments covered with nativevegetation, almost all rain that falls is promptly taken up by the vegeta-tion's roots and transpired back into the atmosphere, leaving the soil belowthe root layer dry. However, when a farmer clears the native vegetation topractice crop-and-fallow agriculture, in which an annual crop like wheat isgrown during one year and the land is left fallow the next year, there areno plant roots to take up rainwater falling in the fallow year. That rain-water accumulates in the soil, waterlogs it below the root layer, and dissolvessalts that then rise into the root zone as the water table rises. Because ofthe impermeable underlying bedrock, the salty water doesn't drain deeplyinto the ground but emerges somewhere downhill nearby as a saline seep.The result is that crops grow more poorly or not at all, both in the uphillarea where the problem arises and in the downhill area where the seepemerges.Saline seeps became widespread in much of Montana after 1940 as aconsequence of changes in agricultural practices—especially the increasinguse of tractors and more efficient soil tilling devices, weed-killers to killweed plant cover during the fallow period, and more land under fallow eachyear. The problem must be combatted by various intensive types of farmmanagement, such as sowing salt-tolerant plants in the downhill seep areasto start reclaiming them, decreasing the length of fallow time in the uphillarea by a crop schedule known as flexible cropping, and planting alfalfa andother perennial water-demanding crops with deep roots to take up excesswater from the soil.In the areas of Montana where agriculture depends directly on rainfall,saline seeps are the main salt-related form of land damage. But they are notthe only form. Several million acres of agricultural land that depend for theirwater on irrigation rather than on rainfall are distributed patchily throughoutthe whole state, including in my summering areas of the Bitter-root Valleyand Big Hole Basin. Salinization is starting to appear in some of those areaswhere the irrigation water contains salt. Another form arises > from anindustrial method to extract methane for natural gas from coal beds bydrilling into the coal and pumping in water to carry the methane up to thesurface. Unfortunately, water dissolves not only methane but also salt. Since1988, the adjacent state of Wyoming, which is almost as poor as Montana, hasbeen seeking to boost its economy by embarking on a big program ofmethane extraction by this method, yielding salty water that drains fromWyoming into southeastern Montana's Powder River Basin.To start to understand the apparently intractable water problems that be-devil Montana along with other dry areas of the American West, think ofthe Bitterroot Valley as having two largely separate water supplies: irrigationfrom ditches fed by mountain streams, lakes, or the Bitterroot River itself, towater fields for agriculture; and wells drilled into underground aquifers,which provide most of the water for domestic use. The valley's larger townsprovide municipal water supplies, but houses outside those few towns allget their water from individual private wells. Both the irrigation water sup-ply and the well water supply are facing the same fundamental dilemma: anincreasing number of users for decreasing amounts of water. As the Bitter-root's water commissioner, Vern Woolsey, explained it succinctly to me,Whenever you have a source of water and more than two people using it,there will be a problem. But why fight about water? Fighting won't makemore water!"The ultimate reason for decreasing amounts of water is climate change:Montana is becoming warmer and drier. While global warming will pro-duce winners as well as losers in different places around the world, Montanawill be among the big losers because its rainfall was already marginally ade-quate for agriculture. Drought has now forced abandonment of large areasof farmland in eastern Montana, as well as in adjacent areas of Alberta andSaskatchewan. Visible effects of global warming in my summering areas inwestern Montana are that snow in the mountains is becoming confined tohigher altitudes and often now no longer remains throughout the summeron the mountains surrounding the Big Hole Basin, as it did when I first vis-ited in 1953.The most visible effect of global warming in Montana, and perhaps any-where in the world, is in Glacier National Park. While glaciers all over theworld are in retreat—on Mt. Kilimanjaro, in the Andes and Alps, on themountains of New Guinea, and around Mt. Everest—the phenomenon hasbeen especially well studied in Montana because its glaciers are so accessibleto climatologists and tourists. When the area of Glacier National Park wasfirst visited by naturalists in the late 1800s, it contained over 150 glaciers;now, there are only about 35 left, mostly at just a small fraction of their first-reported size. At present rates of melting, Glacier National Park will have noglaciers at all by the year 2030. Such declines in the mountain snowpack arebad for irrigation systems, whose summer water comes from melting of thesnow that remains up in the mountains. It's also bad for well systems tap-ping the Bitterroot River's aquifer, whose volume has decreased because ofrecent drought.As in other dry areas of the American West, agriculture would be impos-sible in the Bittterroot Valley without irrigation, because annual rainfall inthe valley bottom is only about 13 inches per year. Without irrigation, thevalley's vegetation would be sagebrush, which is what Lewis and Clark re-ported on their visit in 1805-1806, and which one still sees today as soon asone crosses the last irrigation ditch on the valley's eastern side. Construc-tion of irrigation systems fed by snowmelt water from the high mountainsforming the valley's western side began already in the late 1800s and peakedin 1908-1910. Within each irrigation system or district, each landowner orgroup of landowners has the right to take for his or her land a specifiedquantity of water from the system.Unfortunately, in most Bitterroot irrigation districts the water is "over-allocated." That is—incredibly to a naive outsider like me—the sum of thewater rights allocated to all landowners exceeds the flow of water availablein most years, at least later in the summer when snowmelt is decreasing.Part of the reason is that allocations are calculated on the assumption of afixed water supply, but in fact water supplies vary from year to year with cli-mate, and the assumed fixed water supply is the value for a relatively wetyear. The solution is to assign priorities among landowners according to thehistorical date on which the water right was claimed for that property, andto cut off water deliveries first to the most junior right-owner and then toearlier right-owners as water flows in the ditches decrease. That's already arecipe for conflict, because the oldest farms with the earliest rights claimedare often downhill, and it's hard for uphill farmers with lower-rankingrights to see water that they desperately need flowing merrily downhill pasttheir property and yet to refrain from taking the water. But if they did takeit, their downhill neighbors could sue them.A further problem results from land subdivision: originally the land wasowned in large blocks whose single owner of course took water from theditch for his different fields in sequence, and who wouldn't have been sosilly as to try to water all his fields simultaneously and thus run out of water.But as those original 160-acre blocks have become subdivided each into 40four-acre house lots, there isn't enough water when each of those 40 house-owners tries to water and keep the house's garden green without realizingthat the other 39 neighbors areirrigating simultaneously. Still anotherproblem is that irrigation rights apply only to so-called "beneficial" use ofwater benefitting the piece of land holding the right. Leaving water in theriver for the fish and for the tourists trying to float down the river on rafts isnot considered a "beneficial" right. Sections of the Big Hole River have actu-ally dried up in some recent dry summers. Until 2003, many of those poten-tial conflicts in the Bitterroot Valley were amicably adjudicated for severaldecades by Vern Woolsey, the 82-year-old water commissioner whom every-one respected, but my Bitterroot friends are terrified at the potential forconflict now that Vern has finally stepped down.Bitterroot irrigation systems include 28 small privately owned damsconstructed across mountain streams, in order to store snowmelt water inthe spring and to release it for irrigating fields in the summer. These damsconstitute ticking time bombs. They were all built a century ago, to weakdesigns now considered primitive and dangerous. They have been main-tained poorly or not at all. Many are at risk of collapses that would floodhouses and property lying below them. Devastating floods resulting fromfailures of two such dams several decades ago convinced the Forest Serviceto declare that a dam's owners, and also any contractor that has ever workedon the dam, bear the liability for damages caused by a dam failure. Ownersare responsible for either fixing or removing their dam. While this principlemay seem reasonable, three facts often make it financially onerous: most ofthe present owners bearing the liability get little financial benefit from theirdam and no longer care to fix it (e.g., because the land has been subdividedinto house lots, and they now use the dam just to water their lawns ratherthan to earn a living as farmers); the federal and state governments offermoney on a cost-sharing basis to fix a dam, but not to remove one; and halfof the dams are on lands now designated as wilderness areas, where roadsare forbidden and repair machinery must be flown in by expensive heli-copter charters.One example of such a time bomb is Tin Cup Dam, whose collapsewould inundate Darby, the largest town in the southern Bitterroot Valley.Leaks and the dam's poor condition triggered lengthy arguments and law-suits between the dam's owners, the Forest Service, and environmentalgroups about whether and how to repair the dam, climaxing in an emer-gency when a serious leak was noted in 1998. Unfortunately, the contractorwhom the owners hired to drain the dam's reservoir soon encounteredheavy rocks whose removal would require big excavation equipment to beflown in by helicopter. At that point the owners declared that they had runout of money, and both the state of Montana and Ravalli County also de-cided against spending money on the dam, but the situation remained a po-tentially life-threatening emergency for Darby. Hence the Forest Serviceitself hired the helicopters and equipment to work on the dam and billedthe owners, who have not paid; the U.S. Department of Justice is nowpreparing to sue them in order to collect the costs.The Bitterroot's other water supply besides snowmelt-fed irrigationconsists of wells for domestic water use, tapping into underground aquifers.They, too, face the problem of increasing demand for decreasing water.While mountain snowpack and underground aquifers may seem to be sepa-rate, they are in fact coupled: some runoff of used irrigation water may per-colate down through the ground to the aquifers, and some aquifer watermay originate ultimately from snowmelt. Hence the ongoing decrease inMontana's snowpack forebodes a decrease in the aquifers as well.There is no doubt about increasing demand for aquifer water: the Bitter-root's continuing population explosion means more people drinking morewater and flushing more toilets. Roxa French, coordinator for the local Bit-ter Root Water Forum, advises people building new houses to drill theirwells deep, because there are going to be "more straws in the milkshake"—i.e., more wells drilled into the same aquifer and lowering its level. Montanalaw and county regulations about domestic water are currently weak. Thewell that one new house-owner drills may lower the water level of a neigh-bor's well, but it is difficult for the latter person to collect damages. In orderto calculate how much domestic water use an aquifer could support, onewould have to map the aquifer and to measure how rapidly water is flow-ing into it, but—astonishingly—those two elementary steps have not beenaccomplished for any Bitterroot Valley aquifer. The county itself lacks theresources to monitor its aquifers and does not carry out independent as-sessments of water availability when it is considering a developer's appli-cation to build a new house. Instead, the county relies on the developer'sassurance that enough well water will be available for the house.Everything that I have said about water so far concerns water quantity.However, there are also issues of water quality, which rivals western Mon-tana's scenery as its most valuable natural resource because the rivers andirrigation systems originate from relatively pure snowmelt. Despite that ad-vantage, the Bitterroot River is already on Montana's list of "impairedstreams," for several reasons. The most important of those reasons isbuildup of sediments released by erosion, road construction, forest fires,logging, and falling water levels in ditches and streams due to use for irriga-tion. Most of the Bitterroot's watersheds are now already eroded or at risk.A second problem is fertilizer runoff: every farmer growing hay adds at least200 pounds of fertilizer to each acre of land, but it is unknown how muchof that fertilizer ends up in the river. Waste nutrients from septic tanks areyet another increasing hazard to water quality. Finally, as I already explained,toxic minerals draining out of mines are the most serious water qualityproblem in some other parts of Montana, though not in the Bitterroot.Air quality also deserves brief mention. It may at first seem shamelessfor me, as a resident of the American city (Los Angeles) with the worst airquality, to say anything negative about Montana in this regard. In fact, someareas of Montana do suffer seasonally from poor air quality, worst of all inMissoula, whose air (despite improvements since the 1980s) is sometimes asbad as in Los Angeles. Missoula's air problems, exacerbated by winter tem-perature inversions and by its location in a valley that traps air, stem froma combination of vehicle emissions throughout the year, wood-burningstoves in the winter, and forest fires and logging in the summer.Montana's remaining major sets of environmental problems are the linkedones of introductions of harmful non-native species and losses of valuablenative species. These problems especially involve fish, deer and elk, andweeds.Montana originally supported valuable fisheries based on native Cut-throat Trout (Montana's state fish), Bull Trout, Arctic Grayling, and White-fish. All of those species except Whitefish have now declined in Montanafrom a combination of causes whose relative impact varies among thespecies: less water in the mountain streams where they spawn and develop,because of water removal for irrigation; warmer temperatures and moresediment in those streams, because of logging; overfishing; competitionfrom, and in some cases hybridization with, introduced Rainbow Trout,Brook Trout, and Brown Trout; predation by introduced Northern Pike andLake Trout; and infection by an introduced parasite causing whirling dis-ease. For example, Northern Pike, which are voracious fish-eaters, have beenillegally introduced into some western Montana lakes and rivers by fisher-men fond of catching pike, and have virtually eliminated from those lakesand rivers the populations of Bull Trout andCutthroat on which they prey.Similarly, Flathead Lake's formerly robust fishery based on several nativefish species has been destroyed by introduced Lake Trout.Whirling disease was accidentally introduced into the U.S from its na-tive Europe in 1958 when a Pennsylvania fish hatchery imported some Dan-ish fish that proved to be infected with the disease. It has now spreadthroughout most of the western U.S., partly through transport by birds, butespecially as a result of people (including government agencies and privatefish hatcheries) stocking lakes and rivers with infected fish. Once the para-site gets into a body of water, it is impossible to eradicate. By 1994 whirlingdisease had reduced the Rainbow Trout population of the Madison River,Montana's most famous trout stream, by more than 90%.At least whirling disease is not transmissible to humans; it is merely badfor fishing-based tourism. Another introduced disease, chronic wasting dis-ease (CWD) of deer and elk, is of more concern because it might cause anincurably fatal human illness. CWD is the deer/elk equivalent of prion dis-eases in other animals, of which the most notorious are Creutzfeldt-Jakobdisease in humans, mad cow disease or bovine spongiform encephalopathy(BSE) of cattle (transmissible to humans), and scrapie of sheep. These in-fections cause an untreatable degeneration of the nervous system; no hu-man infected with Creutzfeldt-Jakob disease has ever recovered. CWD wasfirst detected in western North American deer and elk in the 1970s, possibly(some people suggest) because deer housed for studies at a western univer-sity in a pen near scrapie-infected sheep were released into the wild aftercompletion of the studies. (Today, such a release would be considered acriminal act.) Further spread from state to state was accelerated by transfersof exposed deer and elk from one commercial game farm to another. We donot know yet whether CWD can be transmitted from deer or elk to people,as can mad cow disease, but the recent deaths of some elk hunters fromCreutzfeldt-Jakob disease have raised alarms in some quarters. The state ofWisconsin, concerned that fear of transmission could cripple the state'sone-billion-dollar-per-year deer hunting industry, is in the process of killing25,000 deer (a desperate solution that sickens everybody involved) in an in-fected area in hopes of controlling the CWD epidemic there.While CWD is potentially Montana's most frightening problem causedby an introduced pest, introduced weeds are already Montana's most expen-sive such problem. About 30 noxious weed species, mostly of Eurasian ori-gin, have become established in Montana after arriving accidentally in hayor as wind-blown seeds, or in one case being introduced intentionally as anattractive ornamental plant whose dangers weren't anticipated. They causedamage in several ways: they are inedible or poorly edible to livestock andwild animals, but they crowd out edible plant species, so they reduce theamount of livestock fodder by up to 90%; some of them are toxic to ani-mals; and they may triple rates of erosion because their roots hold the soilless well than do roots of native grasses.Economically, the two most important of these weeds are Spotted Knap-weed and Leafy Spurge, both now widespread throughout Montana. Spot-ted Knapweed takes over from native grasses by secreting chemicals thatquickly kill them, and by producing vast numbers of seeds. While it can bepulled out by hand from selected small fields, it has now infested 566,000acres in the Bitterroot Valley alone and 5,000,000 acres in all of Montana, anarea far too large for hand-pulling to be feasible. Spotted Knapweed canalso be controlled by herbicides, but the cheaper herbicides that kill it alsokill many other plant species, and the herbicide specific for Spotted Knap-weed is very expensive ($800 per gallon). In addition, it is uncertain whetherthe breakdown products of those herbicides end up in the Bitterroot Riveror in the aquifers used for human drinking water, and whether those prod-ucts themselves have harmful effects. Because Spotted Knapweed has be-come established on large areas of national forest as well as of pastureland,it reduces the fodder production not only for domestic animals but also forwild herbivores in the forest, so that it may have the effect of driving deerand elk from forest down into pastures by reducing the amount of foodavailable in the forest. Leafy Spurge is at present less widespread than knap-weed but much harder to control and impossible to pull out by hand, be-cause it establishes underground roots 20 feet long.Estimates of the direct economic damage that these and other weedscause in Montana are over $100,000,000 per year. Their presence also re-duces real estate values and farm productivity. Above all, they are a hugepain in the neck for farmers, because they cannot be controlled by any sin-gle measure alone but require complex integrated management systems.They force farmers to change many practices simultaneously: pulling outweeds, applying herbicides, changing fertilizer use, releasing insect and fun-gus enemies of weeds, lighting controlled fires, changing mowing schedules,and altering crop rotations and annual grazing practices. All that because ofa few small plants whose dangers were mostly unappreciated at the time,and some of whose seeds arrived unnoticed!Thus, seemingly pristine Montana actually suffers from serious environ-mental problems involving toxic wastes, forests, soils, water, climate change,biodiversity losses, and introduced pests. All of these problems translateinto economic problems. They provide much of the explanation for whyMontana's economy has been declining in recent decades to the point wherewhat was formerly one of our richest states is now one of the poorest.Whether or how these problems become resolved will depend on the at-titudes and values that Montanans hold. But Montana's population is be-coming increasingly heterogeneous and cannot agree on a vision for theirstate's environment and future. Many of my friends commented on thegrowing polarization of opinion. For instance, banker Emil Erhardt ex-plained to me, "There is too much raucous debate here. The prosperity ofthe 1950s meant that all of us were poor then, or we felt poor. There were noextremes of wealth; at least, wealth wasn't visible. Now, we have a two-tieredsociety with lower-income families struggling to survive at the bottom, andthe wealthier newcomers at the top able to acquire enough property thatthey can isolate themselves. In essence, we are zoning by money, not by landuse!The polarization that my friends mention is along many axes: richversus poor, old-timers versus newcomers, those clinging to a traditionallifestyle versus others welcoming change, pro-growth versus anti-growthvoices, those for and against governmental planning, and those with andwithout school-age children. Fueling these disagreements are Montana'sparadoxes that I mentioned near the beginning of this chapter: a state withpoor residents but attracting rich newcomers, even while the state's ownchildren are deserting Montana upon graduating high school.I initially wondered whether Montana's environmental problems andpolarizing disputes might involve selfish behavior on the part of individualswho advanced their own interests in full knowledge that they were simulta-neously damaging the rest of Montana society. This may be true in somecases, such as the proposals of some mining executives to carry out cyanideheap-leach gold extraction despite the abundant evidence of resulting tox-icity problems; the transfers of deer and elk between game farms by somefarm owners despite the known resulting risk of spreading chronic wastingdisease; and the illegal introductions of pike into lakes and rivers by somefishermen for their own fishing pleasure, despite the history of such trans-fers having destroyed many other fisheries. Even in these cases, though, Ihaven't interviewed individuals involved and don't know whether theycould honestly claim that they thought they had been acting safely. When-ever I have actually been able to talk with Montanans, I have found their ac-tions to be consistent with their values, even if those values clash with myown or those of other Montanans. That is, for the most part Montana's dif-ficulties cannot be simplistically attributed to selfish evil people knowinglyand reprehensibly profiting at the expense of neighbors. Instead, they in-volve clashes between people whose own particular backgrounds and valuescause them to favor policies differing from those favored by people with dif-ferent backgrounds and values. Here are some of the points of view cur-rently competing to shape Montana's future.One clash is between "old-timers" and "newcomers": i.e., people born inMontana, of families resident in the state for many generations, respecting alifestyle and economy traditionally built on the three pillars of mining, log-ging, and agriculture, versus recent arrivals or seasonal visitors. All three ofthose economic pillars are now in steep decline in Montana. All but a fewMontana mines are already closed, due to toxic waste problems plus compe-tition from overseas mines with lower costs. Timber sales are now morethan 80% below former peak levels, and most mills and timber businessesother than specialty firms (notably, log cabin home builders) have closedbecause of a combination of factors: increasing public preference for main-taining intact forests, huge costs of forest management and fire suppression,and competition from logging operations in warmer and wetter climateswith inherent advantages over logging operations in cold dry Montana.Agriculture, the third pillar, is also dwindling: for instance, of the 400dairies operating in the Bitterroot Valley in 1964, only nine still exist. Thereasons behind Montana agriculture's decline are more complex than thosebehind the decline in mining and logging, though in the background loomsthe fundamental competitive disadvantage of Montana's cold dry climatefor growing crops and cows as well as trees.Montana farmers today who continue to farm into their old age do it inpart because they love the lifestyle and take great pride in it. As Tim Hulstold me, "It's a wonderful lifestyle to get up before dawn and see the sunrise,to watch hawks fly overhead, and to see deer jump through your hay field toavoid your haying equipment." Jack Hirschy, a rancher whom I met in 1950when he was 29 years old, is still working on his ranch today at the age of 83,while his father Fred rode a horse on his 91st birthday. But "ranching andfarming are hazardous hard work," in the words of Jack's rancher sister Jill.Jack suffered internal injuries and broken ribs from a tractor accident at age77, while Fred was almost killed by a falling tree at age 58. Tim Huls addedto his proud comment about the wonderful lifestyle, "Occasionally I get upat 3 A.M. and work until 10 P.M. This isn't a 9 to 5 job. But none of our chil-dren will sign up for being a farmer if it is 3 A.M. to 10 P.M. every day."That remark by Tim illustrates one reason for the rise and fall of Mon-tana farming: the lifestyle was highly valued by older generations, but manyfarmers' children today have different values. They want jobs that involvesitting indoors in front of computer screens rather than heaving hay bales,and taking off evenings and weekends rather than having to milk cows andharvest hay that don't take evenings and weekends off. They don't want alife forcing them to do literally back-breaking physical work into their 80s,as all three surviving Hirschy brothers and sisters are still doing.Steve Powell explained to me, "People used to expect no more of a farmthan to produce enough to feed themselves; today, they want more out oflife than just getting fed; they want to earn enough to send their kids to col-lege." When John Cook was growing up on a farm with his parents, "At din-nertime, my mother was satisfied to go to the orchard and gather asparagus,and as a boy I was satisfied for fun to go hunting and fishing. Now, kids ex-pect fast food and HBO; if their parents don't provide that, they feel de-prived compared to their peers. In my day a young adult expected to bepoor for the next 20 years, and only thereafter, if you were lucky, might youhope to end up more comfortably. Now, young adults expect to be comfort-able early; a kid's first questions about a job are 'What are the pay, the hours,and the vacations?'" Every Montana farmer whom I know, and who lovesbeing a farmer, is either very concerned whether any of his/her children willwant to carry on the family farm, or already knows that none of them will.Economic considerations now make it difficult for farmers to earn a liv-ing at farming, because farm costs have been rising much faster than farmincome. The price that a farmer receives for milk and beef today is virtuallythe same as 20 years ago, but costs of fuel, farm machinery, fertilizers, andother farm necessities are higher. Rick Laible gave me an example: "Fiftyyears ago, a farmer who wanted to buy a new truck paid for it by selling twocows. Nowadays, a new truck costs around $15,000, but a cow still sells foronly $600, so the farmer would have to sell 25 cows to pay for the truck."That's the logic underlying the following joke that I was told by a Montanafarmer. Question: "What would you do if you were given a million dollars?"Answer: "I love farming, and I would stay here on my money-losing farmuntil I had used up the million dollars!"Those shrinking profit margins, and increasing competition, have madethe Bitterroot Valley's hundreds of formerly self-supporting small farmsuneconomic. First, the farmers found that they needed additional incomefrom outside jobs to survive, and then they had to give up the farm becauseit required too much work on evenings and weekends after the outside job.For instance, 60 years ago Kathy Vaughn's grandparents supported them-selves on a 40-acre farm, and so Kathy and Pat Vaughn bought their own40-acre farm in 1977. With six cows, six sheep, a few pigs, hay, Kathy work-ing as a schoolteacher, and Pat as an irrigation system builder, they fed andraised three children on the farm, but it provided no security or retirementincome. After eight years, they sold the farm, moved into town, and all oftheir children have now left Montana.Throughout the U.S., small farms are being squeezed out by large farms,the only ones able to survive on shrinking profit margins by economies ofscale. But in southwestern Montana it is now impossible for small farmersto become large farmers by buying more land, for reasons succinctly ex-plained by Allen Bjergo: "Agriculture in the U.S. is shifting to areas like Iowaand Nebraska, where no one would live for the fun of it because it isn'tbeautiful as in Montana! Here in Montana, people do want to live for thefun of it, and so they are willing to pay much more for land than agricultureon the land would support. The Bitterroot is becoming a horse valley.Horses are economic because, whereas prices for agricultural products de-pend on the value of the food itself and are not unlimited, many people arewilling to spend anything for horses that yield no economic benefit."Land prices in the Bitterroot are now 10 or 20 times higher than a fewdecades ago. At those prices, carrying costs for a mortgage are far higherthan could be paid by use of the land as a farm. That's the immediate reasonwhy small farmers in the Bitterroot can't survive by expanding, and why thefarms eventually become sold for non-farm use. If old farmers are still liv-ing on their farm when they die, their heirs are forced to sell the land to adeveloper for much more than it would fetch by sale to another farmer, inand present Vanished Edens? A five-point framework * Businesses and the environment The comparative method * Plan of the book few summers ago I visited two dairy farms, Huls Farm and GardarFarm, which despite being located thousands of miles apart were stillremarkably similar in their strengths and vulnerabilities. Both wereby far the largest, most prosperous, most technologically advanced farms intheir respective districts. In particular, each was centered around a magnifi-cent state-of-the-art barn for sheltering and milking cows. Those structures,both neatly divided into opposite-facing rows of cow stalls, dwarfed allother barns in the district. Both farms let their cows graze outdoors in lushpastures during the summer, produced their own hay to harvest in the latesummer for feeding the cows through the winter, and increased their pro-duction of summer fodder and winter hay by irrigating their fields. The twofarms were similar in area (a few square miles) and in barn size, Huls barnholding somewhat more cows than Gardar barn (200 vs. 165 cows, respec-tively). The owners of both farms were viewed as leaders of their respectivesocieties. Both owners were deeply religious. Both farms were located ingorgeous natural settings that attract tourists from afar, with backdrops ofhigh snow-capped mountains drained by streams teaming with fish, andsloping down to a famous river (below Huls Farm) or fjord (below GardarFarm).Those were the shared strengths of the two farms. As for their sharedvulnerabilities, both lay in districts economically marginal for dairying, be-cause their high northern latitudes meant a short summer growing seasonin which to produce pasture grass and hay. Because the climate was thussuboptimal even in good years, compared to dairy farms at lower latitudes,both farms were susceptible to being harmed by climate change, withdrought or cold being the main concerns in the districts of Huls Farm orGardar Farm respectively. Both districts lay far from population centers townich they could market their products, so that transportation costs andAhazards placed them at a competitive disadvantage compared to more cen-trally located districts. The economies of both farms were hostage to forcesbeyond their owners' control, such as the changing affluence and tastes oftheir customers and neighbors. On a larger scale, the economies of thecountries in which both farms lay rose and fell with the waxing and waningof threats from distant enemy societies.The biggest difference between Huls Farm and Gardar Farm is in theircurrent status. Huls Farm, a family enterprise owned by five siblings andtheir spouses in the Bitterroot Valley of the western U.S. state of Montana, iscurrently prospering, while Ravalli County in which Huls Farm lies boastsone of the highest population growth rates of any American county. Tim,Trudy, and Dan Huls, who are among Huls Farm's owners, personally tookme on a tour of their high-tech new barn, and patiently explained to me theattractions and vicissitudes of dairy farming in Montana. It is inconceivablethat the United States in general, and Huls Farm in particular, will collapsein the foreseeable future. But Gardar Farm, the former manor farm of theNorse bishop of southwestern Greenland, was abandoned over 500 yearsago. Greenland Norse society collapsed completely: its thousands of inhabi-tants starved to death, were killed in civil unrest or in war against an enemy,or emigrated, until nobody remained alive. While the strongly built stonewalls of Gardar barn and nearby Gardar Cathedral are still standing, so thatI was able to count the individual cow stalls, there is no owner to tell me to-day of Gardar's former attractions and vicissitudes. Yet when Gardar Farmand Norse Greenland were at their peak, their decline seemed as inconceiv-able as does the decline of Huls Farm and the U.S. today.Let me make clear: in drawing these parallels between Huls and GardarFarms, I am not claiming that Huls Farm and American society are doomedto decline. At present, the truth is quite the opposite: Huls Farm is in theprocess of expanding, its advanced new technology is being studied foradoption by neighboring farms, and the United States is now the most pow-erful country in the world. Nor am I claiming that farms or societies in gen-eral are prone to collapse: while some have indeed collapsed like Gardar,others have survived uninterruptedly for thousands of years. Instead, mytrips to Huls and Gardar Farms, thousands of miles apart but visited duringthe same summer, vividly brought home to me the conclusion that even therichest, technologically most advanced societies today face growing envi-ronmental and economic problems that should not be underestimated.Many of our problems are broadly similar to those that undermined GardarFarm and Norse Greenland, and that many other past societies also strug-gled to solve. Some of those past societies failed (like the Greenland Norse),and others succeeded (like the Japanese and Tikopians). The past offers usa rich database from which we can learn, in order that we may keep onsucceeding.Norse Greenland is just one of many past societies that collapsed or van-ished, leaving behind monumental ruins such as those that Shelley imag-ined in his poem "Ozymandias." By collapse, I mean a drastic decrease inhuman population size and/or political/economic/social complexity, over aconsiderable area, for an extended time. The phenomenon of collapses isthus an extreme form of several milder types of decline, and it becomesarbitrary to decide how drastic the decline of a society must be before itqualifies to be labeled as a collapse. Some of those milder types of declineinclude the normal minor rises and falls of fortune, and minor political/economic/social restructurings, of any individual society; one society's con-quest by a close neighbor, or its decline linked to the neighbor's rise, with-out change in the total population size or complexity of the whole region;and the replacement or overthrow of one governing elite by another. Bythose standards, most people would consider the following past societies tohave been famous victims of full-fledged collapses rather than of just minordeclines: the Anasazi and Cahokia within the boundaries of the modernU.S., the Maya cities in Central America, Moche and Tiwanaku societies inSouth America, Mycenean Greece and Minoan Crete in Europe, Great Zim-babwe in Africa, Angkor Wat and the Harappan Indus Valley cities in Asia,and Easter Island in the Pacific Ocean (map, pp. 4-5).The monumental ruins left behind by those past societies hold a roman-tic fascination for all of us. We marvel at them when as children we firstlearn of them through pictures. When we grow up, many of us plan vaca-tions in order to experience them at firsthand as tourists. We feel drawn totheir often spectacular and haunting beauty, and also to the mysteries thatthey pose. The scales of the ruins testify to the former wealth and powerof their builders—they boast "Look on my works, ye mighty, and despair!" inShelley's words. Yet the builders vanished, abandoning the great structuresthat they had created at such effort. How could a society that was once somighty end up collapsing? What were the fates of its individual citizens?—did they move away, and (if so) why, or did they die there in some unpleas-ant way? Lurking behind this romantic mystery is the nagging thought:might such a fate eventually befall our own wealthy society? Will touristssomeday stare mystified at the rusting hulks of New York's skyscrapers,much as we stare today at the jungle-overgrown ruins of Maya cities?It has long been suspected that many of those mysterious abandon-ments were at least partly triggered by ecological problems: people inadver-tently destroying the environmental resources on which their societiesdepended. This suspicion of unintendedorder to pay the estate taxes on the great increase in land value during thedeceased farmer's lifetime. More often, the farm is sold by the old farmersthemselves. Much as they cringe at seeing the land that they have farmedand loved for 60 years subdivided into 5-acre lots of suburban sprawl, therise in land prices lets them sell even a small formerly self-supporting farmto a developer for a million dollars. They have no other choice to obtain themoney necessary to support themselves after retirement, because they havenot been able to save money as farmers, and because their children don'twant to continue farming anyway. In Rick Laible's words, "For a farmer, hisland is his only pension fund."What accounts for the enormous jump in land prices? Basically, it's be-cause the Bitterroot's gorgeous environment attracts wealthy newcomers.The people who buy out old farmers are either those new arrivals them-selves, or else land speculators who will subdivide the farm into lots to sellto newcomers or to wealthy people already living in the valley. Almost all ofthe valley's recent 4%-per-year population growth represents newcomersmoving in from outside the valley, not an excess of births over deaths withinthe valley. Seasonal recreational tourism is also on the increase, thanks toout-of-staters (like Stan Falkow, Lucy Tompkins, and my sons) visiting tofly-fish, golf, or hunt. As a recent economic analysis commissioned byRavalli County explains it, "There should be no mystery as to why so manyresidents are coming to the Bitterroot Valley. Simply put, it is a very attrac-tive place to live with its mountains, forests, streams, wildlife, views andvistas, and relatively mild climate."The largest group of immigrants consists of "half-retirees" or early re-tirees in the age bracket 45-59, supporting themselves by real estate equityfrom their out-of-state homes that they sold, and often also by income thatthey continue to earn from their out-of-state businesses or Internet busi-nesses. That is, their sources of support are immune to the economic prob-lems associated with Montana's environment. For example, a Californianwho sells a tiny house in California for $500,000 can use that money inMontana to buy five acres of land with a large house and horses, go fishing,and support herself in her early retirement with savings and with what re-mains of her cashed-out California house equity. Hence nearly half of therecent immigrants to the Bitterroot have been Californians. Because theyare buying Bitterroot land for its beauty and not for the value of the cows orapples that it could produce, the price that they are willing to offer forBitterroot land bears no relation to what the land would be worth if usedfor agriculture.But that huge jump in house prices has created a housing problem forBitterroot Valley residents who have to support themselves by working.Many end up unable to afford houses, having to live in mobile homes orrecreational vehicles or with their parents, and having to hold two or threejobs simultaneously to support even that spartan lifestyle.Naturally, these cruel economic facts create antagonism between theold-time residents and the new arrivals from out-of-state, especially richout-of-staters who maintain a second, third, or even fourth home in Mon-tana (in addition to their homes in San Francisco, Palm Springs, andFlorida), and who visit for just short periods each year in order to fish,hunt, golf, or ski. The old-timers complain about the noisy private jetplanes flying rich visitors in and out of Hamilton Airport within a singleday from their home in San Francisco, just to spend a few hours playing golfat their fourth home on the Stock Farm. Old-timers resent outsiders buyingup large former farms that local residents would also like to buy but can nolonger afford, and on which the locals could formerly get permission tohunt or fish, but now the new landowners want to hunt or fish there exclu-sively with their rich friends and keep out the locals. Misunderstandingsarise from the clash of values and expectations: for instance, newcomerswant elk to come down from the mountains to ranch areas, because theylook pretty or in order to hunt them, but old-timers don't want elk to comedown and eat their hay.Rich out-of-state homeowners are careful to stay in Montana for lessthan 180 days per year, in order to avoid having to pay Montana income taxand thereby to contribute to the cost of local government and schools. Onelocal told me, "Those outsiders have different priorities from us here: whatthey want is privacy and expensive isolation, and they don't want to be in-volved locally except when they take their out-of-state friends to the localbar to show their friends the rural lifestyle and the quaint local people. Theylike wildlife, fishing, hunting, and the scenery, but they're not part of the lo-cal community." Or, as Emil Erhardt said, "Their attitude is, T came here toride my horse, enjoy the mountains, and go fishing: don't bother me withissues I moved here to get away from.'"But there's another side to the rich out-of-staters. Emil Erhardt added,The Stock Farm provides employment with high-paying jobs, it pays a highfraction of the property taxes for the whole Bitterroot Valley, it pays for itsown security staff, and it doesn't make many demands on the communityor on local government services. Our sheriff doesn't get called to the StockFarm to break up bar fights, and Stock Farm owners don't send their chil-dren to the schools here." John Cook acknowledged, "The plus side of thoserich owners is that if Charles Schwab hadn't bought up all that land, itwouldn't still be providing wildlife habitat and green open space, becausethat land would otherwise have been subdivided by some developer."Because the rich out-of-staters were attracted to Montana by its beauti-ful environment, some of them take good care of their property and be-come leaders in defending the environment and instituting land planning.For example, my summer home for the last seven years has been a rentedhouse situated on the Bitterroot River south of Hamilton, and belonging toa private entity called the Teller Wildlife Refuge. Otto Teller was a rich Cali-fornian who liked to come to Montana to fish for trout. One day, he was in-furiated to encounter large construction machinery dumping dirt into oneof his favorite fishing holes on the Gallatin River. He became further en-raged when he saw how massive clear-cutting carried out by logging com-panies in the 1950s was devastating his beloved trout streams and damagingtheir water quality. In 1984 Otto began buying up prime riverside landalong the Bitterroot River and incorporated it into a private wildlife refugee,which he nevertheless let local people continue to visit in order to hunt andfish. He ultimately donated conservation easements on his land to a non-profit organization called the Montana Land Reliance, in order to ensurethat the land would be managed in perpetuity so as to preserve its environ-mental qualities. Had Otto Teller, that wealthy Californian, not bought that1,600 acres of land, it would have been subdivided for small house lots.The influx of newcomers, the resulting rise in land prices and propertytaxes, the poverty of Montana old-timer residents, and their conservativeattitude towards government and taxes (see below) all contribute to theplight of Montana schools, which are funded largely by property taxes. Be-cause Ravalli County has so little industrial or commercial property, themain source of property taxes there is residential property taxes, and thosehave been rising with the increase in land values. To old-timers and less af-fluent newcomers already on a tight budget, every increase in property taxesis a big deal. Not surprisingly, they often react by voting against proposedschool bonds and supplemental local property tax levies for their schools.As a result, while public schools account for two-thirds of RavalliCounty local government spending, that spending as a percentage of per-sonal income stands last among 24 rural western U.S. counties comparableto Ravalli County, and personal income itself is low in Ravalli County. Evenby the low school-funding standards of the state of Montana, RavalliCounty school funding stands out as low. Most Ravalli County school dis-tricts keep their spending down to the absolute minimum required byMontana state law. The average salaries of Montana schoolteachers rankamong the lowest in the U.S., and especially in Ravalli County those lowsalaries plus soaring land prices make it hard for teachers to afford housing.Montana-born children are leaving the state because many of them as-pire to non-Montana lifestyles, and because those who do aspire to Mon-tana lifestyles can't find jobs within the state. For instance, in the years sinceSteve Powell graduated from Hamilton High School, 70% of his classmateshave left the Bitterroot Valley. Without exception, all of my friends whochose to live in Montana discussed, as a painful subject, whether their chil-dren had remained or would come back. All eight of Allen and JackieBjergo's children, and six of Jill and John Eliel's eight children, are now liv-ing outside Montana.To quote Emil Erhardt again, "We in the Bitterroot Valley export chil-dren. Outside influences, like TV, have now made our children aware ofwhat's available outside the valley, and what's unavailable inside it. Peoplebring their children here because of the outdoors, and because it's a greatplace to bring up kids, but then their children don't want the outdoors." Irecall my own sons, who love coming to Montana to fish for two weeks inthe summer but are accustomed to the urban life of Los Angeles for the restof the year, expressing shock as they came out of a Hamilton fast-foodrestaurant and realized how few urban recreational opportunities wereavailable to the local teenagers who had just waited on them. Hamilton hasthe grand total of two movie theatres, and the nearest mall is 50 miles awayin Missoula. A similar shock grows on many of those Hamilton teenagersthemselves, when they travel outside Montana and realize what they aremissing back at home.Like rural western Americans in general, Montanans tend to be conserva-tive, and suspicious of governmental regulation. That attitude arose histori-cally because early settlers were living at low population density on afrontier far from government centers, had to be self-sufficient, and couldn'tlook to government to solve their problems. Montanans especially bristleat the geographically and psychologically remote federal government inWashington, D.C., telling them what to do. (But they don't bristle at the fed-eral government's money, of which Montana receives and accepts about adollar-and-a-half for every dollar sent from Montana to Washington.) Inthe view of Montanans, the American urban majority that runs the federalgovernment has no comprehension of conditions in Montana. In the viewof federal government managers, Montana's environment is a treasurebelonging to all Americans and is not there just for the private benefit ofMontanans.Even by Montana standards, the Bitterroot Valley is especially conserva-tive and anti-government. That may be due to many early Bitterroot settlershaving come from Confederate states, and to a further influx of bitter right-wing conservatives from Los Angeles after that city's race riots. As ChrisMiller said, "Liberals and Democrats living here weep as they read the re-sults after each election, because the outcomes are so conservative." Extremeproponents of right-wing conservativism in the Bitterroot are members ofthe so-called militias, groups of landowners who hoard weapons, refuse topay taxes, keep all others off their property, and are variously tolerated orelse regarded as paranoid by other valley residents.One consequence of those political attitudes in the Bitterroot is opposi-tion to governmental zoning or planning, and a feeling that landownersshould enjoy the right to do whatever they want with their private property.Ravalli County has neither a county building code nor county-wide zoning.Outside of two towns plus voluntary zoning districts formed by local votersin some rural areas outside towns, there aren't even any restrictions on theuse to which land can be put. For instance, one evening when I was visitingthe Bitterroot with my teenaged son Joshua, he read in the newspaper that amovie he had wanted to see was playing in one of Hamilton's two movietheatres. I asked for directions to that theatre, drove him there, and discov-ered to my astonishment that it had been built recently in an area otherwiseconsisting entirely of farmland, except for an adjacent large biotechnologylaboratory. There were no zoning regulations about that changed use offarmland. In contrast, in many other parts of the U.S. there is sufficientpublic concern about loss of farmland that zoning regulations restrict orprohibit its conversion to commercial property, and voters would be espe-cially horrified at the prospect of a theatre with lots of traffic next to apotentially sensitive biotechnology facility.Montanans are beginning to realize that two of their most cherished atti-tudes are in direct opposition: their pro-individual-rights anti-government-regulation attitude, and their pride in their quality of life. That phrase"quality of life" has come up in virtually every conversation that I have hadwith Montanans about their future. The phrase refers to Montanans' beingable to enjoy, every day of their lives, that beautiful environment which out-of-state tourists like me consider it a privilege to be able to visit for a weekor two each year. The phrase also refers to Montanans' pride in their tradi-tional lifestyle as a rural, low-density, egalitarian population descendedfrom old-timer settlers. Emil Erhardt told me, "In the Bitterroot peoplewant to maintain the essence of a rural quiet little community in whicheveryone is in the same condition, poor and proud of it." Or, as Stan Falkowsaid, "Formerly, when you drove down the road in the Bitterroot, you wavedat any car that passed, because you knew everyone."Unfortunately, by permitting unrestricted land use and thereby makingpossible an influx of new residents, Montanans' long-standing and continu-ing opposition to government regulation is responsible for degradation ofthe beautiful natural environment and quality of life that they cherish. Thiswas best explained to me by Steve Powell: "I tell my real estate agent anddeveloper friends, 'You have to protect the beauty of the landscape, thewildlife, and the agricultural land.' Those are the things that create propertyvalue. The longer we wait to do planning, the less landscape beauty therewill be. Undeveloped land is valuable to the community as a whole: it's animportant part of that 'quality of life' that attracts people here. With in-creasing growth pressure, the same people who used to be anti-governmentare now concerned about growth. They say that their favorite recreationarea is becoming crowded, and they now admit that there have to be rules."When Steve was a Ravalli County commissioner in 1993, he sponsored pub-lic meetings just to start discussion of land use planning and to stimulatethe public to think about it. Tough-looking members of the militias came tothose meetings to disrupt them, openly carrying holsters with guns in orderto intimidate other people. Steve lost his subsequent bid for reelection.It's still unclear how the clash between this resistance to governmentplanning and that need for government planning will be resolved. To quoteSteve Powell again, "People are trying to preserve the Bitterroot as a ruralcommunity, but they can't figure out how to preserve it in a way that wouldlet them surviveeconomically." Land Lindbergh and Hank Goetz made es-sentially the same point: "The fundamental problem here is how we hangon to these attractions that brought us to Montana, while still dealing withthe change that can't be avoided."To conclude this chapter about Montana, largely related in my words, I'llnow let four of my Montanan friends relate in their own words how theycame to be Montanans, and their concerns for Montana's future. Rick Laibleis a newcomer, now a state senator; Chip Pigman, an old-timer and a landdeveloper; Tim Huls, an old-timer and a dairy farmer; and John Cook, anewcomer and a fishing guide.Here is Rick Laible's story: "I was born and brought up in the areaaround Berkeley, California, where I have a business manufacturingwooden store fixtures. My wife Frankie and I were both working hard. Oneday, Frankie looked at me and said, 'You're working 10 to 12 hours a day,seven days a week.' We decided to semi-retire, drove 4,600 miles around theWest to find a place to settle, bought our first house in a remote part of theBitterroots in 1993, and moved to a ranch that we bought near the town ofVictor in 1994. My wife raises Egyptian Arabian horses on the ranch, and Igo back to California once a month for my business that I still own there.We have five children. Our oldest son always wanted to move to Montana,and he manages our ranch. The other four of our kids don't understand theMontana quality of life, don't understand that Montanans are nicer people,and don't understand why their parents moved here."Nowadays, after each of my monthly four-day visits to California, Iwant to get out of there: I feel, 'They're like rats in a cage!' Frankie goes backto California only twice a year to see her grandchildren, and that's enoughof California for her. As an example of what I don't like about California, Iwas recently back there for a meeting, and I had a little free time, so I took awalk on the town street. I noticed that people coming in the other directionlowered their eyes and avoided eye contact with me. When I say 'goodmorning' to people that I don't know in California, they're taken aback.Here, in the Bitterroot, it's the rule that when you pass someone that youdon't know, you make eye contact."As for how I got into politics, I've always had many political opinions.The state assembly legislator for my district here in the Bitterroots decidednot to run and suggested to me that I run instead. He tried to convince me,and so did Frankie. Why did I decide to run? It was 'to put somethingback'—I felt that life has been good to me, and I wanted to make life betterfor local people."The legislative issue in which I'm particularly interested is forest man-agement, because my district is forested and many of my constituents arewoodworkers. The town of Darby, which lies in my district, used to be a richlumber town, and forest management would create jobs for the valley.Originally, there were about seven lumber mills in the valley, but now thereare none, so the valley has lost those jobs and infrastructure. The decisionsabout forest management here are currently made by environmental groupsand the federal government, with the county and state being excluded. I'mworking on forest management legislation that would involve collaborationbetween the three lead parties within the state: federal, state, and countyagencies."Several decades ago Montana was among the top 10 U.S. states in itsper-capita income; now, it stands 49 out of 50, because of the decline of theextraction industries (logging, coal, mines, oil, and gas). Those lost jobswere high-paying union jobs. Of course, we should not go back to over-extraction, of which there was some in the old days. Here in the Bitterroot,both a husband and wife have to work, and often they each have to hold twojobs, in order to make ends meet, yet here we are surrounded by this over-fueled forest. Everybody here, environmentalists or not, agrees that we needsome fuel reduction in our forests. Forest restoration would eliminate over-fueling of the forests, especially of the low small trees. Now, that overfuelingis eliminated just by burning it. The federal government's National Fire Planwould do it by mechanical extraction of the logs, the purpose being to re-duce the biomass of fuel. Most of our American timber comes from Canada!Yet the original mandate of our national forests was to provide a steadystream of timber, and to provide watershed protection. It used to be that25% of the revenue from national forests went to schools, but that nationalforest revenue has decreased greatly recently. More logging would meanmore money for our schools."At present, there is no growth policy for all of Ravalli County! The val-ley's population has grown by 40% in the last decade, and it may grow by40% in the next decade: where will that next 40% go? Can we lock the doorto more people moving in? Do we have the right to lock the door? Should afarmer be forbidden to subdivide and develop his property, and should hebe sentenced to a life of farming? A farmer's money for his retirement is allin his land. If the farmer is forbidden to sell his land for development or tobuild a house, what are you doing to him?"As for the long-term effects of growth, there will be cycles here in thefuture, as there have been in the past, and in one of the cycles the newcom-ers will go back home. Montana will never overdevelop, but Ravalli Countywill continue to develop. There is a huge amount of publicly owned landhere in the county. The price of land here will rise until it gets too high, atwhich point prospective buyers will start a land boom somewhere else withcheaper land. Ultimately, all of the farmland in the valley will be developed."Now, this is Chip Pigman's story: "My mother's grandfather moved herefrom Oklahoma around 1925 and had an apple orchard. My mother grewup here on a dairy and sheep farm, and she now owns a real estate agency intown. My father moved here as a child, was in mining and sugarbeets, andheld a second job in construction; that's how I got into construction. I wasborn and went to school here, and I got my B.A. in accounting at the Uni-versity of Montana nearby in Missoula."For three years I moved to Denver, but I disliked city living and I wasdetermined to move back here, in part because the Bitterroot is a great placeto raise children. My bicycle was stolen within my first two weeks in Denver.I didn't like the city's traffic and large groups of people. My needs are satis-fied here. I was raised without 'culture' and I don't need it. I waited just untilmy stock in the Denver company that employed me was vested, and then Imoved back here. That meant leaving a Denver job paying $35,000 a yearplus fringe benefits, and coming back here to earn $17,000 per year withoutany benefits. I was willing to give up the secure Denver job in order to beable to live in the valley, where I can hike. My wife had never experiencedthat insecurity, but I had always lived with that insecurity in the Bitterroot.Here in the Bitterroot, you have to be a two-income household in order tosurvive, and my parents always had to hold multiple odd jobs. I was pre-pared if necessary to take a nighttime job stocking groceries to earn moneyfor my family. After we returned here, it took five years before I again had anincome at my Denver level, and it was another year or two after that until Ihad health insurance."My business is mainly house construction, plus development of the lessexpensive parcels of raw land—I can't afford to buy and develop high-endparcels. Originally, the lots that I developed used to be ranches, but most ofthem are no longer operating ranches by the time that I acquire them; theyhave already been sold, resold, and possibly subdivided several times sincethey were last farmed. They're already out of production, and they carryknapweed rather than pasture."An exception is my current Hamilton Heights project, a 40-acre formerranch that I acquired and that I'm now trying to subdivide for the first time.I submitted to the county a detailed development plan requiring three setsof approvals, of which I succeeded in getting the first two. But the third andlast step was a public hearing, at which 80 people living nearby appearedand protested on the grounds that subdivision would mean a loss of agri-cultural land. Yes, the lot has good soil and used to be good agriculturalland, but it was no longer in agricultural production when I bought it. Ipaid $225,000 for those 40 acres; it would be impossible to support thathigh cost by agriculture. But public opinion doesn't look at the economics.Instead, neighbors say, 'We like to see open space of farmland or forestaround us.' But how is one to maintain that open space if the lot's seller issomeone in their sixties who needs the money to retire? If the neighborshad wanted to preserve that lot as open land, they should have bought itthemselves. They could have bought it, but they didn't. They want still tocontrol it, even though they don't own it."I was turned down at that public hearing because the county plannersdidn't want to oppose 80 voters shortly before an election. I hadn't negoti-ated with the neighbors before submitting my plan, because I am bull-headed, I want to do what I think I have the right to do, and I don't likebeing told what to do. Also, people don't realize that, on a small project likethis one, negotiations are very expensive of my time and money. On a simi-lar project next time, I would talk first with the neighbors, but I would alsobring 50 of my own workers to the hearing, so that the county commission-ers would see that there's also public demand in favor of the project. I'vebeen stuck with the carrying cost of the land during this fight. The neigh-bors would like the land to sit with nothing done to it!"People talk about there being too much development here and thevalley eventually becoming overpopulated, and they try to blame me. Myanswer is: there's demand for my product, the demand isn't something thatI'm creating. Every year there are more buildings and traffic in the valley.But I like to hike, and when you hike or fly over the valley, you see lots ofopen space here. The media say that there was 44% growth in the valley inthe last 10 years, but that just meant a population increase from 25,000 tostill only 35,000 people. Young people are leaving the valley. I have 30 em-ployees, to whom my company gives employment and provides a pensionplan, health insurance, paid vacation, and a profit-sharing plan. No com-petitor offers that package, so I have only low turnover of my workforce. I'mfrequently seen by environmentalists as a cause of the problems in the val-ley, but I can't create demand; someone else will put up the buildings if Idon't."I intend to stay here in the valley for the rest of my life. I belong to thiscommunity, and I support many community projects: for example, I supportthe local baseball, swim, and football teams. Because I'm from here and Iwant to stay here, I don't have a get-rich-and-get-out mentality. I expect stillto be here in 20 years, driving by my old projects. I don't want to look outthen and have to admit to myself, 'That was a bad project that I did!' "Tim Huls is a dairy farmer from an old-timer family: "My great-grand-parents were the first ones in our family to come here in 1912. They bought40 acres when land was still very cheap, and they kept a dozen dairy cowswhich they milked by hand for two hours every morning and then again fortwo hours every evening. My grandparents bought 110 more acres for justpennies per acre, sold cream from their cows' milk to make cheese, andraised apples and hay. However, it was a struggle. There were difficult times,and they hung on by their fingernails, while some other farmers weren'table to. My father considered going to college but decided instead to stay onthe farm. He was the innovative visionary who made the crucial businessdecision to commit himself to specialized dairy farming and to build a 150-cow milking barn, as a way to increase the value obtained from the land."My brothers and I bought the farm from our parents. They didn't giveit to us. Instead, they sold it to us, because they wanted us to decide whoreally wanted badly enough to do farming to be willing to pay for the farm.Each brother and spouse own their own land and lease it to our family cor-poration. Most of the work of running the farm is done by us brothers, ourwives, and our children; we have only a small number of non-family em-ployees. There are very few family farm corporations like ours. One thingthat lets us succeed is that we all share a common religious faith; most of usgo to the same community church in Corvallis. Sure, we do have familyconflicts. But we can have a good fight and still be best friends at night; ourparents fought too, but they always talked about it before sundown. We havefigured out which hills are worth dying on, and which are not."Somehow, that family spirit got passed on to my two sons. The two ofthem learned cooperation as children: when the youngest was still onlyseven years old, they began shifting 40-foot sections of aluminum sprinklerpipe, 16 sections in a line, one boy at each end of a 40-foot section. Afterleaving home, they became roommates, and now they are best friends andneighbors. Other families try to raise their children to maintain family tiesas did our children, but the children of those other families didn't stay to-gether, even though they seemed to be doing the same things that ourfamily did."Farm economics are tough, because the highest value to which land canbe put here in the Bitterroot is for homes and development. Farmers in ourarea face the decision: should we continue farming, or should we sell ourland for home sites and retire? There's no legal crop that would let us com-pete with the house development value of our land, so we can't afford tobuy more land. Instead, what determines our survival is whether we can beas efficient as possible on the 760 acres that we already own or lease. Ourcosts, like the price of pickup trucks, have increased, but we still get thesame money today for 100 pounds of milk as we did 20 years ago. How canwe make a profit on a tighter profit margin? We have to adopt new tech-nology, which takes capital, and we have to continue to educate ourselves onapplying the technology to our circumstances. We have to be willing toabandon old ways."For instance, this year we spent substantial capital to build a new com-puterized 200-cow dairy parlor. It will have automatic manure collection,and a moving fence to push cows towards an automatic milking machinethrough which they'll be moved automatically. Each cow is recognized bycomputer, is milked with a computer at her stall, the conductivity of hermilk is measured at once to detect an infection early, each milking isweighed to track her health and nutritional needs, and the computer's sort-ing criteria let us group cows together into different pens. Our farm is nowserving as a model for the whole state of Montana. Other farmers arewatching us to see if this will work."We have some doubts ourselves whether it will work, because of tworisks beyond our control. But if we're to have any hope of staying in agricul-ture, we had to do this modernization, or else we would have no alternativeto becoming developers: here one either has to grow cows or to grow houseson one's land. One of the two risks beyond our control is price fluctuationsin the farm machinery and services that we have to buy, and in the price weget for our milk. Dairy farmers have no control over the price of milk. Ourmilk is perishable; once the cow is milked, we have only two days to getthat milk off the ranch to market, so we have no bargainingpower. We sellthe milk, and buyers tell us what price it will fetch."The other risk beyond our control is the public's environmental con-cerns, which include our treatment of animals, their wastes, and associatedodor. We try to control these impacts to the best of our ability, but our effortswill probably not please everyone. The newcomers to the Bitterroot come forthe view. At first, they like to see the cows and hayfields in the distance,but sometimes they don't comprehend all that comes with agriculturaloperations, especially dairies. In other areas where dairies and developmentcoexist, the objections to dairies are associated with their odor, the sound ofrunning equipment too late at night, truck traffic on 'our quiet rural road,' andmore. We even had a complaint once when a neighbor got cow manure on herwhite jogging shoes. One of our concerns is that people unsympathetic withanimal agriculture could propose an initiative to restrict or ban dairy farming inour area. For example, two years ago an initiative banning hunting on gamefarms put a Bitterroot elk ranch out of business. We never thought that thatwould happen, and we can't help but feel that there is a possibility that, if we arenot vigilant, it could happen to us. In a society that espouses tolerance, it'samazing how intolerant some folks are to animal agriculture and what comeswith producing food."The last of these four life stories that I'll quote is that of John Cook, the fishingguide who with infinite patience introduced my then-10-year-old sons to fly-fishing and has been taking them out on the Bitterroot River for the last sevensummers: "I grew up on an apple orchard in Washington's We-natchee Valley.At the end of high school I had a wild hippie phase and set off for India on amotorcycle. I only got as far as the U.S. East Coast, but by then I had traveledall over the U.S. After I met my wife Pat, we moved to Washington's OlympicPeninsula and then to Kodiak Island in Alaska, where I worked for 16 years as awildlife and fisheries ranger. We next moved down to Portland, so that Pat couldtake care of her sick grandmother and grandfather. The grandmother died soon,and then one week after the grandfather's death we got out of Portland and cameto Montana."I had first visited Montana in the 1970s, when Pat's father was a wildernessoutfitter working in Idaho's Selway-Bitterroot Wilderness just over the Montanaborder. Pat and I used to work for him part-time, with Pat doing the cooking andme doing the guiding. Already then, Pat loved the Bitterroot River and wanted tolive on it, but land there already cost a thousand dollars per acre, much tooexpensive to support the cost of a mortgage by farming. Then in 1994, when wewere looking to leave Portland, the opportunity arose to buy a 10-acre farm nearthe Bitterroot River at an affordable price. The farmhouse needed someattention, so we spent a few years fixing it up, and I took out a license as anoutfitter and fishing guide."There are only two places in the world to which I feel a deep spiritual bond:one of them is the Oregon coast, and the other is here in the Bitterroot Valley.When we bought this farm, we thought of it as 'dying property':that is, a house where we wanted to live for the rest of our lives. Righthere, on our property, we have great horned owls, pheasants, quail, woodducks, and a pasture big enough for our two horses."People may be born into a time in which they feel that they can live,and they may not want to live in another time. We love this valley as it was30 years ago. Since then, it has been filling up with people. I wouldn't wantto be living here if the valley became a strip mall, with a million people liv-ing on the valley floor between Missoula and Darby. A view of open space isimportant to me. The land across the road from my house is an old farmtwo miles long and half a mile wide, consisting entirely of pastureland, witha couple of barns as the only buildings. It's owned by an out-of-state rocksinger and actor called Huey Lewis, who comes here for just a month or soeach year to hunt and fish, and for the rest of the year has a caretaker whoruns cows, grows hay, and leases some of the land to farmers. If HueyLewis's land across the street got subdivided into house lots, I couldn't standthe sight facing me every day, and I would move."I often think about how I would want to die. My own father recentlydied a slow death of lung disease. He lost control over his own life, and hislast year was painful. I don't want to die that way. It may seem cold-blooded, but here is my fantasy of how I would die if I had my choice. In myfantasy, Pat would die before me. That's because, when we got married, Ipromised to love, honor, and take care of her, and if she died first, I wouldknow that I had fulfilled my promise. Also, I have no life insurance to sup-port her, so it would be hard if she outlived me. After Pat died—my fantasycontinues—I would turn over the deed of the house to my son Cody, then Iwould go trout-fishing every day as long as I was physically in condition todo it. When I became no longer capable of fishing, I would get hold of alarge supply of morphine and go off a long way into the woods. I wouldpick some remote place where nobody would ever find my body, and fromwhich I could enjoy an especially beautiful view. I'd lie down facing thatview and—take my morphine. That would be the best way to die: dying inthe way that I chose, with the last sight I see being a view of Montana as Iwant to remember it."In short, the life stories of these four Montanans, and my own commentspreceding them, illustrate that Montanans differ among themselves in theirvalues and goals. They want more or less population growth, more orless government regulation, more or less development and subdivision ofagricultural land, more or less retention of agricultural uses of land, moreor less mining, and more or less outdoor-based tourism. Some of thesegoals are obviously incompatible with others of them.We have previously seen in this chapter how Montana is experiencingmany environmental problems that translate into economic problems. Ap-plication of these different values and goals that we have just seen illustratedwould result in different approaches to these environmental problems, pre-sumably associated with different probabilities of succeeding or failing atsolving them. At present, there is honest and wide difference of opinionabout the best approaches. We don't know which approaches the citizens ofMontana will ultimately choose, and we don't know whether Montana's en-vironmental and economic problems will get better or worse.It may initially have seemed absurd to select Montana as the subject ofthis first chapter of a book on societal collapses. Neither Montana in par-ticular, nor the U.S. in general, is in imminent danger of collapse. But:please reflect that half of the income of Montana residents doesn't comefrom their work within Montana, but instead consists of money flowinginto Montana from other U.S. states: federal government transfer payments(such as Social Security, Medicare, Medicaid, and poverty programs) andprivate out-of-state funds (out-of-state pensions, earnings on real estateequity, and business income). That is, Montana's own economy already fallsfar short of supporting the Montana lifestyle, which is instead supported byand dependent on the rest of the U.S. If Montana were an isolated island, asEaster Island in the Pacific Ocean was in Polynesian times before Europeanarrival, its present First World economy would already have collapsed, norcould it have developed that economy in the first place.Then reflect that Montana's environmental problems that we have beendiscussing, although serious, are still much less severe than those in most ofthe rest of the U.S., almost all of which has much denser human popula-tions and heavier human impacts, andmuch of which is environmentallymore fragile than Montana. The U.S. in turn depends for essential resourceson, and is economically, politically, and militarily involved with, other partsof the world, some of which have even more severe environmental prob-lems and are in much steeper decline than is the U.S.In the remainder of this book we shall be considering environmentalproblems, similar to Montana's, in various past and modern societies. Forthe past societies that I shall discuss, half of which lack writing, we know farless about individual people's values and goals than we do for Montana. Forthe modern societies, information about values and goals is available, but Imyself have more experience of them in Montana than elsewhere in themodern world. Hence as you read this book, and as you consider environ-mental problems posed mostly in impersonal terms, please think of theproblems of those other societies as viewed by individual people like StanFalkow, Rick Laible, Chip Pigman, Tim Huls, John Cook, and the Hirschybrothers and sisters. When we discuss Easter Island's apparently homoge-neous society in the next chapter, imagine an Easter Island chief, farmer,stone carver, and porpoise fisherman each relating his or her particular lifestory, values, and goals, just as my Montana friends did for me.PART TWOP A S TS O C I E T I E SC H A P T E R 2Twilight at EasterThe quarry's mysteries Easter's geography and history People andfood Chiefs, clans, and commoners Platforms and statues Carving, transporting, erecting The vanished forest Consequences for society Europeans and explanations Why was Easter fragile? Easter as metaphoro other site that I have visited made such a ghostly impression onme as Rano Raraku, the quarry on Easter Island where its famousgigantic stone statues were carved (Plate 5). To begin with, the islandis the most remote habitable scrap of land in the world. The nearest landsare the coast of Chile 2,300 miles to the east and Polynesia's Pitcairn Islands1,300 miles to the west (map, pp. 84-85). When I arrived in 2002 by jetplane from Chile, my flight took more than five hours, all spent over thePacific Ocean stretching endlessly between the horizons, with nothing to seebelow us except water. By the time, towards sunset, that the small low speckthat was Easter Island finally did become dimly visible ahead in the twilight,I had become concerned whether we would succeed in finding the islandbefore nightfall, and whether our plane had enough fuel to return to Chile ifwe overshot and missed Easter. It is hardly an island that one would expectto have been discovered and settled by any humans before the large swiftEuropean sailing ships of recent centuries.Rano Raraku is an approximately circular volcanic crater about 600yards in diameter, which I entered by a trail rising steeply up to the craterrim from the low plain outside, and then dropping steeply down againtoward the marshy lake on the crater floor. No one lives in the vicinity to-day. Scattered over both the crater's outer and inner walls are 397 stone stat-ues, representing in a stylized way a long-eared legless human male torso,mostly 15 to 20 feet tall but the largest of them 70 feet tall (taller than theaverage modern 5-story building), and weighing from 10 up to 270 tons.The remains of a transport road can be discerned passing out of the craterthrough a notch cut into a low point in its rim, from which three moretransport roads about 25 feet wide radiate north, south, and west for up toN9 miles towards Easter's coasts. Scattered along the roads are 97 more stat-ues, as if abandoned in transport from the quarry. Along the coast and oc-casionally inland are about 300 stone platforms, a third of them formerlysupporting or associated with 393 more statues, all of which until a few de-cades ago were not erect but thrown down, many of them toppled so as tobreak them deliberately at the neck.From the crater rim, I could see the nearest and largest platform (calledAhu Tongariki), whose 15 toppled statues the archaeologist Claudio Cris-tino described to me re-erecting in 1994 by means of a crane capable of lift-ing 55 tons. Even with that modern machinery, the task proved challengingfor Claudio, because Ahu Tongariki's largest statue weighed 88 tons. YetEaster Island's prehistoric Polynesian population had owned no cranes, nowheels, no machines, no metal tools, no draft animals, and no means otherthan human muscle power to transport and raise the statues.The statues remaining at the quarry are in all stages of completion.Some are still attached to the bedrock out of which they were being carved,roughed out but with details of the ears or hands missing. Others are fin-ished, detached, and lying on the crater slopes below the niche where theyhad been carved, and still others had been erected in the crater. The ghostlyimpression that the quarry made on me came from my sense of being in afactory, all of whose workers had suddenly quit for mysterious reasons,thrown down their tools, and stomped out, leaving each statue in whateverstage it happened to be at the moment. Littering the ground at the quarryare the stone picks, drills, and hammers with which the statues were beingcarved. Around each statue still attached to rock is the trench in whichthe carvers stood. Chipped in the rock wall are stone notches on which thecarvers may have hung the gourds that served as their water bottles. Somestatues in the crater show signs of having been deliberately broken or de-faced, as if by rival groups of carvers vandalizing one another's products.Under one statue was found a human finger bone, possibly the result ofcarelessness by a member of that statue's transport crew. Who carved thestatues, why did they carve them at such effort, how did the carvers trans-port and raise such huge stone masses, and why did they eventually throwthem all down?Easter's many mysteries were already apparent to its European discov-erer, the Dutch explorer Jacob Roggeveen, who spotted the island on EasterDay (April 5, 1722), hence the name that he bestowed and that has re-mained. As a sailor who had just spent 17 days crossing the Pacific fromChile in three large European ships without any sight of land, Roggeveenasked himself: how had the Polynesians greeting him when he landed onEaster's coast reached such a remote island? We know now that the voyageto Easter from the nearest Polynesian island to the west would have taken atleast as many days. Hence Roggeveen and subsequent European visitorswere surprised to find that the islanders' only watercraft were small andleaky canoes, no more than 10 feet long, capable of holding only one or atmost two people. In Roggeveen's words: "As concerns their vessels, these arebad and frail as regards use, for their canoes are put together with manifoldsmall planks and light inner timbers, which they cleverly stitched togetherwith very fine twisted threads, made from the above-named field-plant. Butas they lacked the knowledge and particularly the materials for caulking andmaking tight the great number of seams of the canoes, these are accordinglyvery leaky, for which reason they are compelled to spend half the time inbailing." How could a band of human colonists plus their crops, chickens,and drinking water have survived a two-and-a-half-week sea journey insuch watercraft?Like all subsequent visitors, including me, Roggeveen was puzzled tounderstand how the islanders had erected their statues. To quote his journalagain, "The stone images at first caused us to be struck with astonishment,because we could not comprehend how it was possible that these people,who are devoid of heavy thick timber for making any machines, as well asstrong ropes, nevertheless had been able to erect such images, which werefully 30 feet high and thick in proportion." No matter what had been the ex-actmethod by which the islanders raised the statues, they needed heavytimber and strong ropes made from big trees, as Roggeveen realized. Yet theEaster Island that he viewed was a wasteland with not a single tree or bushover 10 feet tall (Plates 6, 7): "We originally, from a further distance, haveconsidered the said Easter Island as sandy, the reason for that is this, that wecounted as sand the withered grass, hay, or other scorched and burnt vege-tation, because its wasted appearance could give no other impression thanof a singular poverty and barrenness." What had happened to all the formertrees that must have stood there?Organizing the carving, transport, and erection of the statues required acomplex populous society living in an environment rich enough to supportit. The statues' sheer number and size suggest a population much largerthan the estimated one of just a few thousand people encountered by Euro-pean visitors in the 18th and early 19th centuries: what had happened to theformer large population? Carving, transporting, and erecting statues wouldhave called for many specialized workers: how were they all fed, when theEaster Island seen by Roggeveen had no native land animals larger than in-sects, and no domestic animals except chickens? A complex society is alsoimplied by the scattered distribution of Easter's resources, with its stonequarry near the eastern end, the best stone for making tools in the southwest,the best beach for going out fishing in the northwest, and the best farmlandin the south. Extracting and redistributing all of those products would haverequired a system capable of integrating the island's economy: how could itever have arisen in that poor barren landscape, and what happened to it?All those mysteries have spawned volumes of speculation for almostthree centuries. Many Europeans were incredulous that Polynesians, "meresavages," could have created the statues or the beautifully constructed stoneplatforms. The Norwegian explorer Thor Heyerdahl, unwilling to attributesuch abilities to Polynesians spreading out of Asia across the western Pacific,argued that Easter Island had instead been settled across the eastern Pacificby advanced societies of South American Indians, who in turn must havereceived civilization across the Atlantic from more advanced societies of theOld World. Heyerdahl's famous Kon-Tiki expedition and his other raft voy-ages aimed to prove the feasibility of such prehistoric transoceanic contacts,and to support connections between ancient Egypt's pyramids, the giantstone architecture of South America's Inca Empire, and Easter's giant stonestatues. My own interest in Easter was kindled over 40 years ago by readingHeyerdahl's Kon-Tiki account and his romantic interpretation of Easter'shistory; I thought then that nothing could top that interpretation for excite-ment. Going further, the Swiss writer Erich von Daniken, a believer in vis-its to Earth by extraterrestrial astronauts, claimed that Easter's statues werethe work of intelligent spacelings who owned ultramodern tools, becamestranded on Easter, and were finally rescued.The explanation of these mysteries that has now emerged attributesstatue-carving to the stone picks and other tools demonstrably litteringRano Raraku rather than to hypothetical space implements, and to Easter'sknown Polynesian inhabitants rather than to Incas or Egyptians. This his-tory is as romantic and exciting as postulated visits by Kon-Tiki rafts orextraterrestrials—and much more relevant to events now going on in themodern world. It is also a history well suited to leading off this series ofchapters on past societies, because it proves to be the closest approximationthat we have to an ecological disaster unfolding in complete isolation.Easter is a triangular island consisting entirely of three volcanoes that arosefrom the sea, in close proximity to each other, at different times withinthe last million or several million years, and that have been dormantthroughout the island's history of human occupation. The oldest volcano,Poike, erupted about 600,000 years ago (perhaps as much as 3,000,000 yearsago) and now forms the triangle's southeast corner, while the subsequenteruption of Rano Kau formed the southwest corner. Around 200,000 yearsago, the eruption of Terevaka, the youngest volcano centered near the trian-gle's north corner, released lavas now covering 95% of the island's surface.Easter's area of 66 square miles and its elevation of 1,670 feet are bothmodest by Polynesian standards. The island's topography is mostly gentle,without the deep valleys familiar to visitors to the Hawaiian Islands. Exceptat the steep-sided craters and cinder cones, I found it possible almost any-where on Easter to walk safely in a straight line to anywhere else nearby,whereas in Hawaii or the Marquesas such a walking path would havequickly taken me over a cliff.The subtropical location at latitude 27 degrees south—approximately asfar south of the equator as Miami and Taipei lie north of the equator—givesEaster a mild climate, while its recent volcanic origins give it fertile soils. Bythemselves, this combination of blessings should have endowed the islandwith the makings of a miniature paradise, free from the problems besettingmuch of the rest of the world. Nevertheless, Easter's geography did poseseveral challenges to its human colonists. While a subtropical climate iswarm by the standards of European and North American winters, it is coolby the standards of mostly tropical Polynesia. All other Polynesian-settledislands except New Zealand, the Chathams, Norfolk, and Rapa lie closer tothe equator than does Easter. Hence some tropical crops that are importantelsewhere in Polynesia, such as coconuts (introduced to Easter only in mod-ern times), grow poorly on Easter, and the surrounding ocean is too cold forcoral reefs that could rise to the surface and their associated fish and shell-fish. As Barry Rolett and I found while tramping around on Teravaka andPoike, Easter is a windy place, and that caused problems for ancient farmersand still does today; the wind makes recently introduced breadfruits dropbefore they are ripe. Easter's isolation meant, among other things, that it isdeficient not just in coral-reef fish but in fish generally, of which it has only127 species compared to more than a thousand fish species on Fiji. All ofthose geographic factors resulted in fewer food sources for Easter Islandersthan for most other Pacific Islanders.The remaining problem associated with Easter's geography is its rainfall,on the average only about 50 inches per year: seemingly abundant by thestandards of Mediterranean Europe and Southern California, but low byPolynesian standards. Compounding the limitations imposed by that modestrainfall, the rain that does fall percolates quickly into Easter's porous volcanicsoils. As a consequence, freshwater supplies are limited: just one intermittentstream on Mt. Teravaka's slopes, dry at the time of my visit; ponds or marshes atthe bottoms of three volcanic craters; wells dug down where the water table isnear the surface; and freshwater springs bubbling up on the ocean bottom justoffshore or between the high-tide and low-tide lines. Nevertheless, EasterIslanders did succeed in getting enough water for drinking, cooking, andgrowing crops, but it took effort.Both Heyerdahl and von Daniken brushed aside overwhelming evidence thatthe Easter Islanders were typical Polynesians derived from Asia rather than fromthe Americas, and that their culture (including even their statues) also grew outof Polynesian culture. Their language was Polynesian, as Captain Cook hadalready concluded during his brief visit to Easter in 1774, when a Tahitian manaccompanying him was able to converse with the Easter Islanders. Specifically,they spoke an eastern Polynesian dialect related to Hawaiian and Marquesan,and most closelyrelated to the dialect known as Early Mangarevan. Theirfishhooks, stone adzes, harpoons, coral files, and other tools were typicallyPolynesian and especially resembled early Marquesan models. Many of theirskulls exhibit a characteristically Polynesian feature known as a "rocker jaw."When DNA extracted from 12 skeletons found buried in Easter's stone platformswas analyzed, all 12 samples proved to exhibit a nine-base-pair deletion andthree base substitutions present in most Polynesians. Two of those three basesubstitutions do not occur in Native Americans and thus argue againstHeyerdahl's claim that Native Americans contributed to Easter's gene pool.Easter's crops were bananas, taro, sweet potato, sugarcane, and paper mulberry,typical Polynesian crops mostly of Southeast Asian origin. Easter's soledomestic animal, the chicken, was also typically Polynesian and ultimatelyAsian, as were even the rats that arrived as stowaways in the canoes of the firstsettlers.The prehistoric Polynesian expansion was the most dramatic burst ofoverwater exploration in human prehistory. Until 1200 B.C., the spread of ancienthumans from the Asian mainland through Indonesia's islands to Australia andNew Guinea had advanced no farther into the Pacific than the Solomon Islandseast of New Guinea. Around that time, a seafaring and farming people,apparently originating from the Bismarck Archipelago northeast of New Guinea,and producing ceramics known as Lapita-stylepottery, swept nearly a thousand miles across the open oceans east of theSolomons to reach Fiji, Samoa, and Tonga, and to become the ancestors ofthe Polynesians. While Polynesians lacked compasses and writing and metaltools, they were masters of navigational arts and of sailing canoe tech-nology. Abundant archaeological evidence at radiocarbon-dated sites—such as pottery and stone tools, remains of houses and temples, food debris,and human skeletons—testifies to the approximate dates and routes of theirexpansion. By around A.D. 1200, Polynesians had reached every habitablescrap of land in the vast watery triangle of ocean whose apexes are Hawaii,New Zealand, and Easter Island.Historians used to assume that all those Polynesian islands were discov-ered and settled by chance, as a result of canoes full of fishermen happeningto get blown off course. It is now clear, however, that both the discoveriesand the settlements were meticulously planned. Contrary to what onewould expect for accidental drift voyages, much of Polynesia was settled in awest-to-east direction opposite to that of the prevailing winds and currents,which are from east to west. New islands could have been discovered by voy-agers sailing upwind on a predetermined bearing into the unknown, orwaiting for a temporary reversal of the prevailing winds. Transfers of manyspecies of crops and livestock, from taro to bananas and from pigs to dogsand chickens, prove beyond question that settlement was by well-preparedcolonists, carrying products of their homelands deemed essential to the sur-vival of the new colony.The first expansion wave of Lapita potters ancestral to Polynesiansspread eastwards across the Pacific only as far as Fiji, Samoa, and Tonga,which lie within just a few days' sail of each other. A much wider gap ofocean separates those West Polynesian islands from the islands of East Poly-nesia: the Cooks, Societies, Marquesas, Australs, Tuamotus, Hawaii, NewZealand, Pitcairn group, and Easter. Only after a "Long Pause" of about1,500 years was that gap finally breached—whether because of improve-ments in Polynesian canoes and navigation, changes in ocean currents,emergence of stepping-stone islets due to a drop in sea level, or just onelucky voyage. Some time around A.D. 600-800 (the exact dates are debated),the Cooks, Societies, and Marquesas, which are the East Polynesian islandsmost accessible from West Polynesia, were colonized and became in turnthe sources of colonists for the remaining islands. With New Zealand's oc-cupation around A.D. 1200, across a huge water gap of at least 2,000 miles,the settlement of the Pacific's habitable islands was at last complete.By what route was Easter itself, the Polynesian island farthest east,occupied? Winds and currents would probably have ruled out a direct voy-age to Easter from the Marquesas, which supported a large population anddo seem to have been the immediate source for Hawaii's settlement. In-stead, the jumping-off points for the colonization of Easter are more likelyto have been Mangareva, Pitcairn, and Henderson, which lie about halfwaybetween the Marquesas and Easter, and the fates of whose populations willbe the story of our next chapter (Chapter 3). The similarity between Easter'slanguage and Early Mangarevan, the similarity between a Pitcairn statueand some Easter statues, the resemblances of Easter tool styles to Mangare-van and Pitcairn tool styles, and the correspondence of Easter Island skullsto two Henderson Island skulls even more closely than to Marquesan skullsall suggest use of Mangareva, Pitcairn, and Henderson as stepping-stones.In 1999 the reconstructed Polynesian sailing canoe Hokuk'a succeeded inreaching Easter from Mangareva after a voyage of 17 days. To us modernlandlubbers, it is literally incredible that canoe voyagers sailing east fromMangareva could have had the good luck to hit an island only nine mileswide from north to south after such a long voyage. However, Polynesiansknew how to anticipate an island long before land became visible, from theflocks of nesting seabirds that fly out over a radius of a hundred miles fromland to forage. Thus, the effective diameter of Easter (originally home tosome of the largest seabird colonies in the whole Pacific) would have been arespectable 200 miles to Polynesian canoe-voyagers, rather than a merenine.Easter Islanders themselves have a tradition that the leader of the expe-dition to settle their island was a chief named Hotu Matu'a ("the Great Par-ent") sailing in one or two large canoes with his wife, six sons, and extendedfamily. (European visitors in the late 1800s and early 1900s recorded manyoral traditions from surviving islanders, and those traditions contain muchevidently reliable information about life on Easter in the century or so be-fore European arrival, but it is uncertain whether the traditions accuratelypreserve details about events a thousand years earlier.) We shall see (Chap-ter 3) that the populations of many other Polynesian islands remained incontact with each other through regular interisland two-way voyaging aftertheir initial discovery and settlement. Might that also have been true ofEaster, and might other canoes have arrived after Hotu Matu'a? Archaeolo-gist Roger Green has suggested that possibility for Easter, on the basis ofsimilarities between some Easter tool styles and the styles of Mangarevantools at a time several centuries after Easter's settlement. Against that possi-bility, however, stands Easter's traditional lack of dogs, pigs, and some typi-cal Polynesian crops that one might have expected subsequent voyagers tohave brought if those animals and crops had by chance failed to survive inHotu Matu'a's canoe or had died out soon after his arrival. In addition, weshall see in the next chapter that finds of numerous tools made of stonewhose chemical composition is distinctive for one island, turning up on an-other island, unequivocally prove interisland voyaging between the Mar-quesas, Pitcairn, Henderson, Mangareva, and Societies, but no stone ofEaster origin has been found on any other island or vice versa. Thus, EasterIslanders may have remained effectively completely isolated at the end ofthe world, with no contact with outsiders for the thousand years or so sepa-rating Hotu Matu'a's arrival from Roggeveen's.Given that East Polynesia's main islands may have been settled aroundA.D. 600-800, when was Easter itself occupied?There is considerable uncer-tainty about the date, as there is for the settlement of the main islands. Thepublished literature on Easter Island often mentions possible evidence forsettlement at A.D. 300-400, based especially on calculations of language di-vergence times by the technique known as glottochronology, and on threeradiocarbon dates from charcoal in Ahu Te Peu, in the Poike ditch, and inlake sediments indicative of forest clearance. However, specialists on EasterIsland history increasingly question these early dates. Glottochronologicalcalculations are considered suspect, especially when applied to languageswith as complicated histories as Easter's (known to us mainly through, andpossibly contaminated by, Tahitian and Marquesan informants) and Man-gareva's (apparently secondarily modified by later Marquesan arrivals). Allthree of the early radiocarbon dates were obtained on single samples datedby older methods now superseded, and there is no proof that the charcoalobjects dated were actually associated with humans.Instead, what appear to be the most reliable dates for early occupation ofEaster are the radiocarbon dates of A.D. 900 that paleontologist DavidSteadman and archaeologists Claudio Cristino and Patricia Vargas obtainedon wood charcoal and on bones of porpoises eaten by people, from the old-est archaeological layers offering evidence of human presence at Easter'sAnakena Beach. Anakena is by far the best canoe landing beach on the island,the obvious site at which the first settlers would have based themselves. Thedating of the porpoise bones was done by the modern state-of-the-art radio-carbon method known as AMS (accelerator mass spectrometry), and a so-called marine reservoir correction for radiocarbon dating of bones ofmarine creatures like porpoises was roughly estimated. These dates arelikely to be close to the time of first settlement, because they came fromarchaeological layers containing bones of native land birds that were exter-minated very quickly on Easter and many other Pacific islands, and becausecanoes to hunt porpoises soon became unavailable. Hence the current bestestimate of Easter's settlement is somewhat before A.D. 900.What did the islanders eat, and how many of them were there?At the time of European arrival, they subsisted mainly as farmers, grow-ing sweet potatoes, yams, taro, bananas, and sugarcane, plus chickens astheir sole domestic animal. Easter's lack of coral reefs or of a lagoon meantthat fish and shellfish made a smaller contribution to the diet than on mostother Polynesian islands. Seabirds, land birds, and porpoises were availableto the first settlers, but we shall see that they declined or disappeared later.The result was a high-carbohydrate diet, exacerbated by the islanders' com-pensating for Easter's limited sources of fresh water by copiously drinkingsugarcane juice. No dentist would be surprised to learn that the islandersended up with the highest incidence of cavities and tooth decay of anyknown prehistoric people: many children already had cavities by age 14, andeveryone did by their 20s.Easter's population at its peak has been estimated by methods such ascounting the number of house foundations, assuming 5 to 15 people perhouse, and assuming one-third of identified houses to have been occupiedsimultaneously, or by estimating the numbers of chiefs and their followersfrom the numbers of platforms or erected statues. The resulting estimatesrange from a low of 6,000 to a high of 30,000 people, which works out to anaverage of 90 to 450 people per square mile. Some of the island's area, suchas the Poike Peninsula and the highest elevations, was less suitable for agri-culture, so that population densities on the better land would have beensomewhat higher, but not much higher because archaeological surveysshow that a large fraction of the land surface was utilized.As usual anywhere in the world when archaeologists debate rival esti-mates for prehistoric population densities, those preferring the lower esti-mates refer to the higher estimates as absurdly high, and vice versa. My ownopinion is that the higher estimates are more likely to be correct, in part be-cause those estimates are by the archaeologists with the most extensiverecent experience of surveying Easter: Claudio Cristino, Patricia Vargas, Ed-mundo Edwards, Chris Stevenson, and Jo Anne Van Tilburg. In addition,the earliest reliable estimate of Easter's population, 2,000 people, was madeby missionaries who took up residence in 1864 just after an epidemic ofsmallpox had killed off most of the population. And that was after the kid-napping of about 1,500 islanders by Peruvian slave ships in 1862-63, aftertwo previous documented smallpox epidemics dating back to 1836, afterthe virtual certainty of other undocumented epidemics introduced by regu-lar European visitors from 1770 onwards, and after a steep population crashthat began in the 1600s and that we shall discuss below. The same shipthat brought the third smallpox epidemic to Easter went on to the Mar-quesas, where the resulting epidemic is known to have killed seven-eighthsof the population. For these reasons it seems to me impossible that the1864 post-smallpox population of 2,000 people represented the residue of apre-smallpox, pre-kidnapping, pre-other-epidemic, pre-17th-century-crashpopulation of only 6,000 to 8,000 people. Having seen the evidence for in-tensive prehistoric agriculture on Easter, I find Claudio's and Edmundo's"high" estimates of 15,000 or more people unsurprising.That evidence for agricultural intensification is of several types. Onetype consists of stone-lined pits 5 to 8 feet in diameter and up to 4 feet deepthat were used as composting pits in which to grow crops, and possibly alsoas vegetable fermentation pits. Another type of evidence is a pair of stonedams built across the bed of the intermittent stream draining the southeast-ern slope of Mt. Terevaka, in order to divert water onto broad stone plat-forms. That water diversion system resembles systems for irrigated taroproduction elsewhere in Polynesia. Still further evidence for agricultural in-tensification is numerous stone chicken houses (called hare mod), mostly upto 20 feet long (plus a few 70-foot monsters), 10 feet wide, and 6 feet high,with a small entrance near the ground for chickens to run in and out, andwith an adjacent yard ringed by a stone wall to prevent the precious chick-ens from running away or being stolen. If it were not for the fact thatEaster's abundant big stone hare moa are overshadowed by its even biggerstone platforms and statues, tourists would remember Easter as the islandof stone chicken houses. They dominate much of the landscape near thecoast, because today the prehistoric stone chicken houses—all 1,233 ofthem—are much more conspicuous than the prehistoric human houses,which had only stone foundations or patios and no stone walls.But the most widespread method adopted to increase agricultural out-put involved various uses of lava rocks studied by archaeologist ChrisStevenson. Large boulders were stacked as windbreaks to protect plantsfrom being dried out by Easter's frequent strong winds. Smaller boulderswere piled to create protected aboveground or sunken gardens, for growingbananas and also for starting seedlings to be transplanted after they hadgrown larger. Extensive areas of ground were partly covered by rocks placedat close intervals on the surface, such that plants could come up between therocks. Other large areas were modified by so-called "lithic mulches," whichmeans partly filling the soil with rocks down to a depth of a foot, either bycarrying rocks from nearby outcrops or else by digging down to and break-ing up bedrock. Depressions for planting taro were excavated into naturalgravel fields. All of these rock windbreaks and gardens involved a huge ef-fort to construct, because they requiredmoving millions or even billions ofrocks. As archaeologist Barry Rolett, who has worked in other parts of Poly-nesia, commented to me when he and I made our first visit to Easter to-gether, "I have never been to a Polynesian island where people were sodesperate, as they were on Easter, that they piled small stones together in acircle to plant a few lousy small taro and protect them against the wind! Onthe Cook Islands, where they have irrigated taro, people will never stoop tothat effort!"Indeed, why did farmers go to all that effort on Easter? On farms in thenortheastern U.S. where I spent my boyhood summers, farmers exertedthemselves to carry stones out of fields, and would have been horrified atthe thought of intentionally bringing stones into the fields. What good doesit do to have a rocky field?The answer has to do with Easter's windy, dry, cool climate that I alreadydescribed. Rock garden or lithic mulch agriculture was invented indepen-dently by farmers in many other dry parts of the world, such as Israel'sNegev desert, southwestern U.S. deserts, and dry parts of Peru, China, Ro-man Italy, and Maori New Zealand. Rocks make the soil moister by coveringit, reducing evaporative water loss due to sun and wind, and replacing ahard surface crust of soil that would otherwise promote rain runoff. Rocksdamp out diurnal fluctuations in soil temperature by absorbing solar heatduring the day and releasing it at night; they protect soil against beingeroded by splashing rain droplets; dark rocks on lighter soil warm up thesoil by absorbing more solar heat; and rocks may also serve as slow-time-release fertilizer pills (analogous to the slow-time-release vitamin pills thatsome of us take with breakfast), by containing needed minerals that gradu-ally become leached out into the soil. In modern agricultural experimentsin the U.S. Southwest designed to understand why the ancient Anasazi(Chapter 4) used lithic mulches, it turned out that the mulches yielded bigadvantages to farmers. Mulched soils ended up with double the soil mois-ture content, lower maximum soil temperatures during the day, higherminimum soil temperatures at night, and higher yields for every one of 16plant species grown—four times higher yields averaged over the 16 species,and 50 times higher yields of the species most benefited by the mulch.Those are enormous advantages.Chris Stevenson interprets his surveys as documenting the spread ofrock-assisted intensive agriculture on Easter. For about the first 500 years ofPolynesian occupation, in his view, farmers remained in the lowlandswithin a few miles of the coast, in order to be closer to freshwater sourcesand fishing and shellflshing opportunities. The first evidence for rock gar-dens that he can discern appears around A.D. 1300, in higher-elevation in-land areas that have the advantage of higher rainfall than coastal areas butcooler temperatures (mitigated by the use of dark rocks to raise soil temper-atures). Much of Easter's interior was converted into rock gardens. Interest-ingly, it seems clear that farmers themselves didn't live in the interior,because there are remains of only small numbers of commoners' housesthere, lacking chicken houses and with only small ovens and garbage piles.Instead, there are scattered elite-type houses, evidently for resident upper-class managers who ran the extensive rock gardens as large-scale plantations(not as individual family gardens) to produce surplus food for the chiefs' la-bor force, while all the peasants continued to live near the coast and walkedback and forth several miles inland each day. Roads five yards wide withstone edges, running between the uplands and the coast, may mark theroutes of those daily commutes. Probably the upland plantations did not re-quire year-round effort: the peasants just had to march up and plant taroand other root crops in the spring, then return later in the year for theharvest.As elsewhere in Polynesia, traditional Easter Island society was divided intochiefs and commoners. To archaeologists today, the difference is obviousfrom remains of the different houses of the two groups. Chiefs and mem-bers of the elite lived in houses termed hare paenga, in the shape of a longand slender upside-down canoe, typically around 40 feet long (in one case,310 feet), not more than 10 feet wide, and curved at the ends. The house'swalls and roof (corresponding to the canoe's inverted hull) were of threelayers of thatch, but the floor was outlined by neatly cut and fitted founda-tion stones of basalt. Especially the curved and beveled stones at each endwere difficult to make, prized, and stolen back and forth between rival clans.In front of many hare paenga was a stone-paved terrace. Hare paenga werebuilt in the 200-yard-broad coastal strip, 6 to 10 of them at each major site,immediately inland of the site's platform bearing the statues. In contrast,houses of commoners were relegated to locations farther inland, weresmaller, and were associated each with its own chicken house, oven, stonegarden circle, and garbage pit—utilitarian structures banned by religioustapu from the coastal zone containing the platforms and the beautiful harepaenga.Both oral traditions preserved by the islanders, and archaeological sur-veys, suggest that Easter's land surface was divided into about a dozen (ei-ther 11 or 12) territories, each belonging to one clan or lineage group, andeach starting from the seacoast and extending inland—as if Easter were apie cut into a dozen radial wedges. Each territory had its own chief and itsown major ceremonial platforms supporting statues. The clans competedpeacefully by seeking to outdo each other in building platforms and statues,but eventually their competition took the form of ferocious fighting. Thatdivision into radially sliced territories is typical for Polynesian islands else-where in the Pacific. What is unusual in that respect about Easter is that,again according to both oral traditions and archaeological surveys, thosecompeting clan territories were also integrated religiously, and to some ex-tent economically and politically, under the leadership of one paramountchief. In contrast, on both Mangareva and the larger Marquesan islandseach major valley was an independent chiefdom locked in chronic fiercewarfare against other chiefdoms.What might account for Easter's integration, and how was it detectablearchaeologically? It turns out that Easter's pie does not consist of a dozenidentical slices, but that different territories were endowed with differentvaluable resources. The most obvious example is that Tongariki territory(called Hotu Iti) contained Rano Raraku crater, the island's only source ofthe best stone for carving statues, and also a source of moss for caulking ca-noes. The red stone cylinders on top of some statues all came from PunaPau quarry in Hanga Poukura territory. Vinapu and Hanga Poukura terri-tories controlled the three major quarries of obsidian, the fine-grained vol-canic stone used for making sharp tools, while Vinapu and Tongariki hadthe best basalt for hare paenga slabs. Anakena on the north coast had thetwo best beaches for launching canoes, while Heki'i, its neighbor on thesame coast, had the third best beach. As a result, artifacts associated withfishing have been found mainly on that coast. But those same north-coastterritories have the poorest land for agriculture, the best land being alongthe south and west coasts. Only five of the dozen territories had extensiveareas of interior uplands used for rock-garden plantations. Nesting seabirdseventually became virtually confined to a few offshore islets along the southcoast, especially in Vinapu territory. Other resources such as timber, coralfor making files, red ochre, and paper mulberry trees (the source of barkpounded into tapa cloth) were also unevenly distributed.The clearest archaeological evidence forecological suicide—ecocide—hasbeen confirmed by discoveries made in recent decades by archaeologists,climatologists, historians, paleontologists, and palynologists (pollen scien-tists). The processes through which past societies have undermined them-selves by damaging their environments fall into eight categories, whoserelative importance differs from case to case: deforestation and habitat de-struction, soil problems (erosion, salinization, and soil fertility losses), wa-ter management problems, overhunting, overfishing, effects of introducedspecies on native species, human population growth, and increased per-capita impact of people.Those past collapses tended to follow somewhat similar courses consti-tuting variations on a theme. Population growth forced people to adoptintensified means of agricultural production (such as irrigation, double-cropping, or terracing), and to expand farming from the prime lands firstchosen onto more marginal land, in order to feed the growing number ofhungry mouths. Unsustainable practices led to environmental damage ofone or more of the eight types just listed, resulting in agriculturally mar-ginal lands having to be abandoned again. Consequences for society in-cluded food shortages, starvation, wars among too many people fightingfor too few resources, and overthrows of governing elites by disillusionedmasses. Eventually, population decreased through starvation, war, or dis-ease, and society lost some of the political, economic, and cultural com-plexity that it had developed at its peak. Writers find it tempting to drawanalogies between those trajectories of human societies and the trajectoriesof individual human lives—to talk of a society's birth, growth, peak, senes-cence, and death—and to assume that the long period of senescence thatmost of us traverse between our peak years and our deaths also applies tosocieties. But that metaphor proves erroneous for many past societies (andfor the modern Soviet Union): they declined rapidly after reaching peaknumbers and power, and those rapid declines must have come as a surpriseand shock to their citizens. In the worst cases of complete collapse, every-body in the society emigrated or died. Obviously, though, this grim trajec-tory is not one that all past societies followed unvaryingly to completion:different societies collapsed to different degrees and in somewhat differentways, while many societies didn't collapse at all.The risk of such collapses today is now a matter of increasing concern;indeed, collapses have already materialized for Somalia, Rwanda, and someother Third World countries. Many people fear that ecocide has now cometo overshadow nuclear war and emerging diseases as a threat to global civi-lization. The environmental problems facing us today include the sameeight that undermined past societies, plus four new ones: human-causedclimate change, buildup of toxic chemicals in the environment, energyshortages, and full human utilization of the Earth's photosynthetic capacity.Most of these 12 threats, it is claimed, will become globally critical withinthe next few decades: either we solve the problems by then, or the problemswill undermine not just Somalia but also First World societies. Much morelikely than a doomsday scenario involving human extinction or an apoca-lyptic collapse of industrial civilization would be "just" a future of signifi-cantly lower living standards, chronically higher risks, and the underminingof what we now consider some of our key values. Such a collapse could as-sume various forms, such as the worldwide spread of diseases or else ofwars, triggered ultimately by scarcity of environmental resources. If this rea-soning is correct, then our efforts today will determine the state of theworld in which the current generation of children and young adults livesout their middle and late years.But the seriousness of these current environmental problems is vigor-ously debated. Are the risks greatly exaggerated, or conversely are they un-derestimated? Does it stand to reason that today's human population ofalmost seven billion, with our potent modern technology, is causing our en-vironment to crumble globally at a much more rapid rate than a mere fewmillion people with stone and wooden tools already made it crumble locallyin the past? Will modern technology solve our problems, or is it creatingnew problems faster than it solves old ones? When we deplete one resource(e.g., wood, oil, or ocean fish), can we count on being able to substitutesome new resource (e.g., plastics, wind and solar energy, or farmed fish)?Isn't the rate of human population growth declining, such that we're alreadyon course for the world's population to level off at some manageable num-ber of people?All of these questions illustrate why those famous collapses of past civili-zations have taken on more meaning than just that of a romantic mystery.Perhaps there are some practical lessons that we could learn from all thosepast collapses. We know that some past societies collapsed while others didn't:what made certain societies especially vulnerable? What, exactly, were theprocesses by which past societies committed ecocide? Why did some pastsocieties fail to see the messes that they were getting into, and that (one wouldthink in retrospect) must have been obvious? Which were the solutions thatsucceeded in the past? If we could answer these questions, we might be able toidentify which societies are now most at risk, and what measures could best helpthem, without waiting for more Somalia-like collapses.But there are also differences between the modern world and its problems,and those past societies and their problems. We shouldn't be so naive as to thinkthat study of the past will yield simple solutions, directly transferable to oursocieties today. We differ from past societies in some respects that put us atlower risk than them; some of those respects often mentioned include ourpowerful technology (i.e., its beneficial effects), globalization, modernmedicine, and greater knowledge of past societies and of distant modernsocieties. We also differ from past societies in some respects that put us atgreater risk than them: mentioned in that connection are, again, our potenttechnology (i.e., its unintended destructive effects), globalization (such that nowa collapse even in remote Somalia affects the U.S. and Europe), the dependenceof millions (and, soon, billions) of us on modern medicine for our survival, andour much larger human population. Perhaps we can still learn from the past, butonly if we think carefully about its lessons.Efforts to understand past collapses have had to confront one major controversyand four complications. The controversy involves resistance to the idea that pastpeoples (some of them known to be ancestral to peoples currently alive andvocal) did things that contributed to their own decline. We are much moreconscious of environmental damage now than we were a mere few decades ago.Even signs in hotel rooms now invoke love of the environment to make us feelguilty if we demand fresh towels or let the water run. To damage theenvironment today is considered morally culpable.Not surprisingly, Native Hawaiians and Maoris don't like paleontologiststelling them that their ancestors exterminated half of the bird species that hadevolved on Hawaii and New Zealand, nor do Native Americans likearchaeologists telling them that the Anasazi deforested parts of the southwesternU.S. The supposed discoveries by paleontologists and archaeolo-gists sound to some listeners like just one more racist pretext advanced bywhites for dispossessing indigenous peoples. It's as if scientists were saying,"Your ancestors were bad stewards of their lands, so they deserved to be dis-possessed." Some American and Australian whites, resentful of governmentpayments and land retribution to Native Americans and Aboriginal Aus-some degree of integrationamong the competing clan territories is that stone statues and their redcylinders, from quarries in the territories of the Tongariki and HangaPoukura clans respectively, ended up on platforms in all 11 or 12 territoriesdistributed all over the island. Hence the roads to transport the statues andcrowns out of those quarries over the island also had to traverse many terri-tories, and a clan living at a distance from the quarries would have neededpermission from several intervening clans to transport statues and cylindersacross the latter's territories. Obsidian, the best basalt, fish, and other local-ized resources similarly became distributed all over Easter. At first, thatseems only natural to us moderns living in large politically unified coun-tries like the U.S.: we take it for granted that resources from one coast areroutinely transported long distances to other coasts, traversing many otherstates or provinces en route. But we forget how complicated it has usuallybeen throughout history for one territory to negotiate access to another ter-ritory's resources. A reason why Easter may thus have become integrated,while large Marquesan islands never did, is Easter's gentle terrain, contrast-ing with Marquesan valleys so steep-sided that people in adjacent valleyscommunicated with (or raided) each other mainly by sea rather thanoverland.We now return to the subject that everyone thinks of first at the mention ofEaster Island: its giant stone statues (termed moat), and the stone platforms(termed ahu) on which they stood. About 300 ahu have been identified, ofwhich many were small and lacked moai, but about 113 did bear moai, and25 of them were especially large and elaborate. Each of the island's dozenterritories had between one and five of those large ahu. Most of the statue-bearing ahu are on the coast, oriented so that the ahu and its statues facedinland over the clan's territory; the statues do not look out to sea.The ahu is a rectangular platform, made not of solid stone but of rubblefill held in place by four stone retaining walls of gray basalt. Some of thosewalls, especially those of Ahu Vinapu, have beautifully fitted stones reminis-cent of Inca architecture and prompting Thor Heyerdahl to seek connec-tions with South America. However, the fitted walls of Easter ahu just havestone facing, not big stone blocks as do Inca walls. Nevertheless, one of Easter'sfacing slabs still weighs 10 tons, which sounds impressive to us until wecompare it with the blocks of up to 361 tons at the Inca fortress of Sac-sahuaman. The ahu are up to 13 feet high, and many are extended by lateralwings to a width of up to 500 feet. Hence an ahu's total weight—from about 300tons for a small ahu, up to more than 9,000 tons for Ahu Tongariki— dwarfs thatof the statues that it supports. We shall return to the significance of this pointwhen we estimate the total effort involved in building Easter's ahu and moai.An ahu's rear (seaward) retaining wall is approximately vertical, but thefront wall slopes down to a flat rectangular plaza about 160 feet on each side. Inback of an ahu are crematoria containing the remains of thousands of bodies. Inthat practice of cremation, Easter was unique in Polynesia, where bodies wereotherwise just buried. Today the ahu are dark gray, but originally they were amuch more colorful white, yellow, and red: the facing slabs were encrusted withwhite coral, the stone of a freshly cut moai was yellow, and the moai's crownand a horizontal band of stone coursing on the front wall of some ahu were red.As for the moai, which represent high-ranking ancestors, Jo Anne VanTilburg has inventoried a total of 887 carved, of which nearly half still remain inRano Raraku quarry, while most of those transported out of the quarry wereerected on ahu (between 1 and 15 per ahu). All statues on ahu were of RanoRaraku tuff, but a few dozen statues elsewhere (the current count is 53) werecarved from other types of volcanic stone occurring on the island (variouslyknown as basalt, red scoria, gray scoria, and trachyte). The "average" erectedstatue was 13 feet tall and weighed about 10 tons. The tallest ever erectedsuccessfully, known as Paro, was 32 feet tall but was slender and weighed"only" about 75 tons, and was thus exceeded in weight by the 87-ton slightlyshorter but bulkier statue on Ahu Tongariki that taxed Claudio Cristino in hisefforts to reerect it with a crane. While islanders successfully transported astatue a few inches taller than Paro to its intended site on Ahu Hanga Te Tenga,it unfortunately fell over during the attempt to erect it. Rano Raraku quarrycontains even bigger unfinished statues, including one 70 feet long and weighingabout 270 tons. Knowing what we do about Easter Island technology, it seemsimpossible that the islanders could ever have transported and erected it, and wehave to wonder what megalomania possessed its carvers.To extraterrestrial-enthusiast Erich von Daniken and others, Easter Island'sstatues and platforms seemed unique and in need of special expla-nation. Actually, they have many precedents in Polynesia, especially in EastPolynesia. Stone platforms called marae, used as shrines and often support-ing temples, were widespread; three were formerly present on Pitcairn Is-land, from which the colonists of Easter might have set out. Easter's ahudiffer from marae mainly in being larger and not supporting a temple. TheMarquesas and Australs had large stone statues; the Marquesas, Australs,and Pitcairn had statues carved of red scoria, similar to the material usedfor some Easter statues, while another type of volcanic stone called a tuff(related to Rano Raraku stone) was also used in the Marquesas; Mangarevaand Tonga had other stone structures, including on Tonga a well-known bigtrilithon (a pair of vertical stone pillars supporting a horizontal crosspiece,each pillar weighing about 40 tons); and there were wooden statues onTahiti and elsewhere. Thus, Easter Island architecture grew out of an exist-ing Polynesian tradition.We would of course love to know exactly when Easter Islanders erectedtheir first statues, and how styles and dimensions changed with time. Un-fortunately, because stone cannot be radiocarbon-dated, we are forced torely on indirect dating methods, such as radiocarbon-dated charcoal foundin ahu, a method known as obsidian-hydration dating of cleaved obsidiansurfaces, styles of discarded statues (assumed to be early ones), and succes-sive stages of reconstruction deduced for some ahu, including those thathave been excavated by archaeologists. It seems clear, however, that laterstatues tended to be taller (though not necessarily heavier), and that thebiggest ahu underwent multiple rebuildings with time to become larger andmore elaborate. The ahu-building period seems to have fallen mainly in theyears A.D. 1000-1600. These indirectly derived dates have recently gainedsupport from a clever study by J. Warren Beck and his colleagues, who ap-plied radiocarbon dating to the carbon contained in the coral used for filesand for the statues' eyes, and contained in the algae whose white nodulesdecorated the plaza. That direct dating suggests three phases of construc-tion and reconstruction of Ahu Nau Nau at Anakena, the first phase aroundA.D. 1100 and the last phase ending around 1600. The earliest ahu wereprobably platforms without any statues, like Polynesian marae elsewhere.Statues inferred to be early were reused in the walls of later ahu and otherstructures. They tend to be smaller, rounder, and more human than lateones, and to be made of various types of volcanic stone other than RanoRaraku tuff.Eventually, Easter Islanders settled on the volcanic tuff from RanoRaraku, for the simple reason that it was infinitely superior for carving. TheI!tuff has a hard surface but an ashlike consistency inside and is thus easier tocarve thanvery hard basalt. As compared to red scoria, the tuff is less break-able and lends itself better to polishing and to carving of details. With time,insofar as we can infer relative dates, Rano Raraku statues became larger,more rectangular, more stylized, and almost mass-produced, although eachstatue is slightly different from others. Paro, the tallest statue ever erected,was also one of the latest.The increase in statue size with time suggests competition between rivalchiefs commissioning the statues to outdo each other. That conclusion alsoscreams from an apparently late feature called a pukao: a cylinder of redscoria, weighing up to 12 tons (the weight of Paro's pukao), mounted as aseparate piece to rest on top of a moai's flat head (Plate 8). (When you readthat, just ask yourself: how did islanders without cranes manipulate a 12-ton block so that it balanced on the head of a statue up to 32 feet tall? Thatis one of the mysteries that drove Erich von Daniken to invoke extraterres-trials. The mundane answer suggested by recent experiments is that thepukao and statue were probably erected together.) We don't know for surewhat the pukao represented; our best guess is a headdress of red birds'feathers prized throughout Polynesia and reserved for chiefs, or else a hat offeathers and tapa cloth. For instance, when a Spanish exploring expeditionreached the Pacific island of Santa Cruz, what really impressed the localpeople was not Spanish ships, swords, guns, or mirrors, but their red cloth.All pukao are of red scoria from a single quarry, Puna Pau, where (just as istrue of moai at the moai workshop on Rano Raraku) I observed unfinishedpukao, plus finished ones awaiting transport.We know of not more than a hundred pukao, reserved for statues on thebiggest and richest ahu built late in Easter prehistory. I cannot resist thethought that they were produced as a show of one-upsmanship. They seemto proclaim: "All right, so you can erect a statue 30 feet high, but look at me:I can put this 12-ton pukao on top of my statue; you try to top that, youwimp!" The pukao that I saw reminded me of the activities of Hollywoodmoguls living near my home in Los Angeles, similarly displaying theirwealth and power by building ever larger, more elaborate, more ostenta-tious houses. Tycoon Marvin Davis topped previous moguls with his houseof 50,000 square feet, so Aaron Spelling had to top that with a house of56,000 square feet. All that those moguls' houses lack to make explicit theirmessage of power is a 12-ton red pukao on the house's highest tower, raisedinto position without resort to cranes.Given the widespread distribution over Polynesia of platforms and stat-ues, why were Easter Islanders the only ones to go overboard, to make by far thelargest investment of societal resources in building them, and to erect the biggestones? At least four different factors cooperated to produce that outcome. First,Rano Raraku tuff is the best stone in the Pacific for carving: to a sculptor used tostruggling with basalt and red scoria, it almost cries out, "Carve me!" Second,other Pacific island societies on islands within a few days' sail of other islandsdevoted their energy, resources, and labor to interisland trading, raiding,exploration, colonization, and emigration, but those competing outlets wereforeclosed for Easter Islanders by their isolation. While chiefs on other Pacificislands could compete for prestige and status by seeking to outdo each other inthose interisland activities, "The boys on Easter Island didn't have those usualgames to play," as one of my students put it. Third, Easter's gentle terrain andcomplementary resources in different territories led as we have seen to someintegration of the island, thereby letting clans all over the island obtain RanoRaraku stone and go overboard in carving it. If Easter had remained politicallyfragmented, like the Marquesas, the Tongariki clan in whose territory RanoRaraku lay could have monopolized its stone, or neighboring clans could havebarred transport of statues across their territories—as in fact eventuallyhappened. Finally, as we shall see, building platforms and statues requiredfeeding lots of people, a feat made possible by the food surpluses produced bythe elite-controlled upland plantations.How did all those Easter Islanders, lacking cranes, succeed in carving, trans-porting, and erecting those statues? Of course we don't know for sure, becauseno European ever saw it being done to write about it. But we can make informedguesses from oral traditions of the islanders themselves (especially abouterecting statues), from statues in the quarries at successive stages of completion,and from recent experimental tests of different transport methods.In Rano Raraku quarry one can see incomplete statues still in the rock faceand surrounded by narrow carving canals only about two feet wide. The hand-held basalt picks with which the carvers worked are still at the quarry. The mostincomplete statues are nothing more than a block of stone roughly carved out ofthe rock with the eventual face upwards, and with the back still attached to theunderlying cliff below by a long keel of rock. Next to be carved were the head,nose, and ears, followed by the arms, hands, and loincloth. At that stage the keelconnecting the statue's back to the cliff waschipped through, and transport of the statue out of its niche began. All stat-ues in the process of being transported still lack the eye sockets, which wereevidently not carved until the statue had been transported to the ahu anderected there. One of the most remarkable recent discoveries about the stat-ues was made in 1979 by Sonia Haoa and Sergio Rapu Haoa, who foundburied near an ahu a separate complete eye of white coral with a pupil ofred scoria. Subsequently, fragments of other similar eyes were unearthed.When such eyes are inserted into a statue, they create a penetrating, blind-ing gaze that is awesome to look at. The fact that so few eyes have been re-covered suggests that few actually were made, to remain under guard bypriests, and to be placed in the sockets only at times of ceremonies.The still-visible transport roads on which statues were moved fromquarries follow contour lines to avoid the extra work of carrying statues upand down hills, and are up to nine miles long for the west-coast ahu farthestfrom Rano Raraku. While the task may strike us as daunting, we know thatmany other prehistoric peoples transported very heavy stones at Stone-henge, Egypt's pyramids, Teotihuacan, and centers of the Incas and Olmecs,and something can be deduced of the methods in each case. Modern schol-ars have experimentally tested their various theories of statue transport onEaster by actually moving statues, beginning with Thor Heyerdahl, whosetheory was probably wrong because he damaged the tested statue in theprocess. Subsequent experimenters have variously tried hauling statues ei-ther standing or prone, with or without a wooden sled, and on or not on aprepared track of lubricated or unlubricated rollers or else with fixed cross-bars. The method most convincing to me is Jo Anne Van Tilburg's sugges-tion that Easter Islanders modified the so-called canoe ladders that werewidespread on Pacific islands for transporting heavy wooden logs, whichhad to be cut in the forest and shaped there into dugout canoes and thentransported to the coast. The "ladders" consist of a pair of parallel woodenrails joined by fixed wooden crosspieces (not movable rollers) over whichthe log is dragged. In the New Guinea region I have seen such ladders morethan a mile long, extending from the coast hundreds of feet uphill to a for-est clearing at which a huge tree was being felled and then hollowed outto make a canoe hull. We know that some of the biggest canoes that theHawaiians moved over canoe ladders weighed more than an average-sizeEaster Island moai, so theproposed method is plausible.Jo Anne enlisted modern Easter Islanders to put her theory to a test bybuilding such a canoe ladder, mounting a statue prone on a wooden sled,attaching ropes to the sled, and hauling it over the ladder. She found that 50to 70 people, working five hours per day and dragging the sled five yards ateach pull, could transport an average-sized 12-ton statue nine miles in aweek. The key, Jo Anne and the islanders discovered, was for all of thosepeople to synchronize their pulling effort, just as canoe paddlers synchro-nize their paddling strokes. By extrapolation, transport of even big statueslike Paro could have been accomplished by a team of 500 adults, whichwould have been just within the manpower capabilities of an Easter Islandclan of one or two thousand people.Easter Islanders told Thor Heyerdahl how their ancestors had erectedstatues on ahu. They were indignant that archaeologists had never deignedto ask them, and they erected a statue for him without a crane to prove theirpoint. Much more information has emerged in the course of subsequent ex-periments on transporting and erecting statues by William Mulloy, Jo AnneVan Tilburg, Claudio Cristino, and others. The islanders began by buildinga gently sloping ramp of stones from the plaza up to the top of the front ofthe platform, and pulling the prone statue with its base end forwards up theramp. Once the base had reached the platform, they levered the statue'shead an inch or two upwards with logs, slipped stones under the head tosupport it in the new position, and continued to lever up the head andthereby to tilt the statue increasingly towards the vertical. That left the ahu'sowners with a long ramp of stones, which may then have been dismantledand recycled to create the ahu's lateral wings. The pukao was probablyerected at the same time as the statue itself, both being mounted together inthe same supporting frame.The most dangerous part of the operation was the final tilting of thestatue from a very steep angle to the vertical position, because of the riskthat the statue's momentum in that final tilt might carry it beyond the verti-cal and tip it off the rear of the platform. Evidently to reduce that risk, thecarvers designed the statue so that it was not strictly perpendicular to its flatbase but just short of perpendicular (e.g., at an angle of about 87 degrees tothe base, rather than 90 degrees). In that way, when they had raised thestatue to a stable position with the base flat on the platform, the body wasstill leaning slightly forwards and at no risk of tipping over backwards. Theycould then slowly and carefully lever up the front edge of the base that finalfew degrees, slipping stones under the front of the base to stabilize it, untilthe body was vertical. But tragic accidents could still occur at that last stage,as evidently happened in the attempt to erect at Ahu Hanga Te Tenga astatue even taller than Paro, which ended with its tipping over and breaking.The whole operation of constructing statues and platforms must havebeen enormously expensive of food resources for whose accumulation,transport, and delivery the chiefs commissioning the statues must havearranged. Twenty carvers had to be fed for a month, they may also havebeen paid in food, then a transport crew of 50 to 500 people and a similarerecting crew had to be fed while doing hard physical work and thus requir-ing more food than usual. There must also have been much feasting for thewhole clan owning the ahu, and for the clans across whose territories thestatue was transported. Archaeologists who first tried to calculate the workperformed, the calories burned, and hence the food consumed overlookedthe fact that the statue itself was the smaller part of the operation: an ahuoutweighed its statues by a factor of about 20 times, and all that stone forthe ahu also had to be transported. Jo Anne Van Tilburg and her architecthusband Jan, whose business it is to erect large modern buildings in Los An-geles and to calculate the work involved for cranes and elevators, did arough calculation of the corresponding work on Easter. They concludedthat, given the number and size of Easter's ahu and moai, the work of con-structing them added about 25% to the food requirements of Easter's popu-lation over the 300 peak years of construction. Those calculations explainChris Stevenson's recognition that those 300 peak years coincided with thecenturies of plantation agriculture in Easter's interior uplands, producing alarge food surplus over that available previously.However, we have glossed over another problem. The statue operationrequired not only lots of food, but also lots of thick long ropes (made inPolynesia from fibrous tree bark) by which 50 to 500 people could drag stat-ues weighing 10 to 90 tons, and also lots of big strong trees to obtain all thetimber needed for the sleds, canoe ladders, and levers. But the Easter Islandseen by Roggeveen and subsequent European visitors had very few trees, allof them small and less than 10 feet tall: the most nearly treeless island inall of Polynesia. Where were the trees that provided the required rope andtimber?Botanical surveys of plants living on Easter within the 20th century haveidentified only 48 native species, even the biggest of them (the toromiro, upto seven feet tall) hardly worthy of being called a tree, and the rest of themlow ferns, grasses, sedges, and shrubs. However, several methods for recov-ering remains of vanished plants have shown within the last few decadesthat, for hundreds of thousands of years before human arrival and still dur-ing the early days of human settlement, Easter was not at all a barren waste-land but a subtropical forest of tall trees and woody bushes.The first such method to yield results was the technique of pollen analy-sis (palynology), which involves boring out a column of sediment depositedin a swamp or pond. In such a column, provided that it has not been shakenor disturbed, the surface mud must have been deposited most recently,while more deeply buried mud represents more ancient deposits. The actualage of each layer in the deposit can be dated by radiocarbon methods. Thereremains the incredibly tedious task of examining tens of thousands ofpollen grains in the column under a microscope, counting them, and thenidentifying the plant species producing each grain by comparison withmodern pollen from known plant species. For Easter Island the first bleary-eyed scientist to perform that task was the Swedish palynologist Olof Sell-ing, who examined cores collected from the swamps in Rano Raraku's andRano Kau's craters by Heyerdahl's 1955 expedition. He detected abundantpollen of an unidentified species of palm tree, of which Easter today has nonative species.In 1977 and 1983 John Flenley collected many more sediment cores andagain noticed abundant palm pollen, but by good luck Flenley in 1983 alsoobtained from Sergio Rapu Haoa some fossil palm nuts that visiting Frenchcave explorers had discovered that year in a lava cave, and he sent them tothe world's leading palm expert for identification. The nuts turned out to bevery similar to, but slightly larger than, those of the world's largest existingpalm tree, the Chilean wine palm, which grows up to 65 feet tall and 3 feetin diameter. Subsequent visitors to Easter have found more evidence of thepalm, in the form of casts of its trunks buried in Mt. Terevaka's lava flows afew hundred thousand years ago, and casts of its root bundles proving thatthe Easter palm's trunk reached diameters exceeding seven feet. It thusdwarfed even the Chilean palm and was (while it existed) the biggest palmin the world.Chileans prize their palm today for several reasons, and Easter Islanderswould have done so as well. As the name implies, the trunk yields a sweetsap that can be fermented to make wine or boiled down to make honey orsugar.The nuts' oily kernels are rated a delicacy. The fronds are ideal forfabricating into house thatching, baskets, mats, and boat sails. And ofcourse the stout trunks would have served to transport and erect moai, andperhaps to make rafts.Flenley and Sarah King recognized pollen of five other now-extinct treesin the sediment cores. More recently, the French archaeologist CatherineOrliac has been sieving out 30,000 fragments of wood burned to charcoalfrom cores dug into Easter Island ovens and garbage heaps. With a heroismmatching that of Selling, Flenley, and King, she has compared 2,300 of thosecarbonized wood fragments to wood samples of plants still existing todayelsewhere in Polynesia. In that way she has identified about 16 other plantspecies, most of them trees related to or the same as tree species still wide-spread in East Polynesia, that formerly grew on Easter Island as well. Thus,Easter used to support a diverse forest.Many of those 21 vanished species besides the palm would have beenvaluable to the islanders. Two of the tallest trees, Alphitonia cf. zizyphoidesand Elaeocarpus cf. rarotongensis (up to 100 and 50 feet tall respectively), areused elsewhere in Polynesia for making canoes and would have been muchbetter suited to that purpose than was the palm. Polynesians everywheremake rope from the bark of the hauhau Triumfetta semitriloba, and that waspresumably how Easter Islanders dragged their statues. Bark of the papermulberry Broussonetia papyrifera is beaten into tapa cloth; Psydrax odoratahas a flexible straight trunk suited for making harpoons and outriggers; theMalay apple Syzygium malaccense bears an edible fruit; the oceanic rose-wood Thespesia populanea and at least eight other species have hardwoodsuitable for carving and construction; toromiro yields an excellent wood forfires, like acacia and mesquite; and the fact that Orliac recovered all of thosespecies as burnt fragments from fires proves that they too were used forfirewood.The person who pored through 6,433 bones of birds and other verte-brates from early middens at Anakena Beach, probably the site of the firsthuman landing and first settlement on Easter, was zooarchaeologist DavidSteadman. As an ornithologist myself, I bow in awe before Dave's identifica-tion skills and tolerance of eye strain: whereas I wouldn't know how to tell arobin's bone from a dove's or even from a rat's, Dave has learned how to dis-tinguish even the bones of a dozen closely related petrel species from eachother. He thereby proved that Easter, which today supports not a singlespecies of native land bird, was formerly home to at least six of them, in-cluding one species of heron, two chicken-like rails, two parrots, and a barnowl. More impressive was Easter's prodigious total of at least 25 nestingseabird species, making it formerly the richest breeding site in all of Polyne-sia and probably in the whole Pacific. They included albatross, boobies,frigatebirds, fulmars, petrels, prions, shearwaters, storm-petrels, terns, andtropicbirds, attracted by Easter's remote location and complete lack ofpredators that made it an ideal safe haven as a breeding site—until humansarrived. Dave also recovered a few bones of seals, which breed today on theGalapagos Islands and the Juan Fernandez Islands to the east of Easter, butit is uncertain whether those few seal bones on Easter similarly came fromformer breeding colonies or just vagrant individuals.The Anakena excavations that yielded those bird and seal bones tell usmuch about the diet and lifestyle of Easter's first human settlers. Out ofthose 6,433 vertebrate bones identified in their middens, the most frequentones, accounting for more than one-third of the total, proved to belong tothe largest animal available to Easter Islanders: the Common Dolphin, aporpoise weighing up to 165 pounds. That's astonishing: nowhere else inPolynesia do porpoises account for even as much as 1% of the bones inmiddens. The Common Dolphin generally lives out to sea, hence it couldnot have been hunted by line-fishing or spear-fishing from shore. Instead, itmust have been harpooned far offshore, in big seaworthy canoes built fromthe tall trees identified by Catherine Orliac.Fish bones also occur in the middens but account there for only 23% ofall bones, whereas elsewhere in Polynesia they were the main food (90% ormore of all the bones). That low contribution of fish to Easter diets was be-cause of its rugged coastline and steep drop-offs of the ocean bottom, sothat there are few places to catch fish by net or handline in shallow water.For the same reason the Easter diet was low in molluscs and sea urchins. Tocompensate, there were those abundant seabirds plus the land birds. Birdstew would have been seasoned with meat from large numbers of rats,which reached Easter as stowaways in the canoes of the Polynesian colonists.Easter is the sole known Polynesian island at whose archaeological sites ratbones outnumber fish bones. In case you're squeamish and consider ratsinedible, I still recall, from my years of living in England in the late 1950s,recipes for creamed laboratory rat that my British biologist friends whokept them for experiments also used to supplement their diet during theiryears of wartime food rationing.Porpoises, fish, shellfish, birds, and rats did not exhaust the list of meatsources available to Easter's first settlers. I already mentioned a few sealrecords, and other bones testify to the occasional availability of sea turtlesand perhaps of large lizards. All those delicacies were cooked over firewoodthat can be identified as having come from Easter's subsequently vanishedforests.Comparison of those early garbage deposits with late prehistoric ones orwith conditions on modern Easter reveals big changes in those initiallybountiful food sources. Porpoises, and open-ocean fish like tuna, virtuallydisappeared from the islanders' diet, for reasons to be mentioned below.The fish that continued to be caught were mainly inshore species. Landbirds disappeared completely from the diet, for the simple reason that everyspecies became extinct from some combination of overhunting, deforesta-tion, and predation by rats. It was the worst catastrophe to befall Pacific is-land birds, surpassing even the record on New Zealand and Hawaii, whereto be sure the moas and flightless geese and other species became extinctbut many other species managed to survive. No Pacific island other thanEaster ended up without any native land birds. Of the 25 or more formerlybreeding seabirds, overharvesting and rat predation brought the result that24 no longer breed on Easter itself, about 9 are now confined to breeding inmodest numbers on a few rocky islets off Easter's coasts, and 15 have beeneliminated on those islets as well. Even shellfish were overexploited, so thatpeople ended up eating fewer of the esteemed large cowries and more ofthe second-choice smaller black snails, and the sizes of both cowry and snailshells in the middens decreased with time because of preferential over-harvesting of larger individuals.The giant palm, and all the other now-extinct trees identified by Cather-ine Orliac, John Flenley, and Sarah King, disappeared for half a dozenreasons that we can document or infer. Orliac's charcoal samples fromovens prove directly that trees were being burned for firewood. They werealso being burned to cremate bodies: Easter crematoria contain remains ofthousands of bodies and huge amounts of human bone ash, implying mas-sive fuel consumption for the purposes of cremation. Trees were beingcleared for gardens, because most of Easter's land surface except at the high-est elevations ended up being used to grow crops. From the early middenabundance of bones of open-ocean porpoises and tuna, we infer that bigtrees like Alphitonia and Elaeocarpus were being felled to make seaworthycanoes; the frail, leaky little watercraftseen by Roggeveen would not haveserved for harpooning platforms or venturing far out to sea. We infer thattrees furnished timber and rope for transporting and erecting statues, andundoubtedly for a multitude of other purposes. The rats introduced acci-dentally as stowaways "used" the palm tree and doubtless other trees fortheir own purposes: every Easter palm nut that has been recovered showstooth marks from rats gnawing on it and would have been incapable ofgerminating.Deforestation must have begun some time after human arrival by A.D.900, and must have been completed by 1722, when Roggeveen arrivedand saw no trees over 10 feet tall. Can we specify more closely when, betweenthose dates of 900 and 1722, deforestation occurred? There are five types ofevidence to guide us. Most radiocarbon dates on the palm nuts themselves arebefore 1500, suggesting that the palm became rare or extinct thereafter. On thePoike Peninsula, which has Easter's most infertile soils and hence was probablydeforested first, the palms disappeared by around 1400, and charcoal from forestclearance disappeared around 1440 although later signs of agriculture attest tocontinued human presence there. Orliac's radiocarbon-dated charcoal samplesfrom ovens and garbage pits show wood charcoal being replaced by herb andgrass fuels after 1640, even at elite houses that might have claimed the lastprecious trees after none was left for the peasants. Flenley's pollen cores showthe disappearance of palm, tree daisy, toromiro, and shrub pollen, and theirreplacement by grass and herb pollen, between 900 and 1300, but radiocarbondates on sediment cores are a less direct clock for deforestation than are directdates on the palms and their nuts. Finally, the upland plantations that ChrisStevenson studied, and whose operation may have paralleled the period ofmaximum timber and rope use for statues, were maintained from the early 1400sto the 1600s. All this suggests that forest clearance began soon after human ar-rival, reached its peak around 1400, and was virtually complete by dates thatvaried locally between the early 1400s and the 1600s.The overall picture for Easter is the most extreme example of forest destructionin the Pacific, and among the most extreme in the world: the whole forest gone,and all of its tree species extinct. Immediate consequences for the islanders werelosses of raw materials, losses of wild-caught foods, and decreased crop yields.Raw materials lost or else available only in greatly decreased amountsconsisted of everything made from native plants and birds, including wood,rope, bark to manufacture bark cloth, and feathers. Lack of large timber and ropebrought an end to the transport and erection of statues, and also to theconstruction of seagoing canoes. When five of Easter's little two-man leakycanoes paddled out to trade with a French ship anchored off Easter in 1838, itscaptain reported, "All the natives repeated often and excitedly the word miru andbecame impatient because they saw that we did not understand it: this word isthe name of the timber used by Polynesians to make their canoes. This was whatthey wanted most, and they used every means to make us understand this . .."The name "Terevaka" for Easter's largest and highestmountain means "place to get canoes": before its slopes were stripped oftheir trees to convert them to plantations, they were used for timber, andthey are still littered with the stone drills, scrapers, knives, chisels, and otherwoodworking and canoe-building tools from that period. Lack of large tim-ber also meant that people were without wood for fuel to keep themselveswarm during Easter's winter nights of wind and driving rain at a tempera-ture of 50 degrees Fahrenheit. Instead, after 1650 Easter's inhabitants werereduced to burning herbs, grasses, and sugarcane scraps and other cropwastes for fuel. There would have been fierce competition for the remainingwoody shrubs, among people trying to obtain thatching and small pieces ofwood for houses, wood for implements, and bark cloth. Even funeral prac-tices had to be changed: cremation, which had required burning muchwood per body, became impractical and yielded to mummification andbone burials.Most sources of wild food were lost. Without seagoing canoes, bones ofporpoises, which had been the islanders' principal meat during the first cen-turies, virtually disappeared from middens by 1500, as did tuna and pelagicfish. Midden numbers of fishhooks and fish bones in general also declined,leaving mainly just fish species that could be caught in shallow water orfrom the shore. Land birds disappeared completely, and seabirds were re-duced to relict populations of one-third of Easter's original species, con-fined to breeding on a few offshore islets. Palm nuts, Malay apples, and allother wild fruits dropped out of the diet. The shellfish consumed becamesmaller species and smaller and many fewer individuals. The only wild foodsource whose availability remained unchanged was rats.In addition to those drastic decreases in wild food sources, crop yieldsalso decreased, for several reasons. Deforestation led locally to soil erosionby rain and wind, as shown by huge increases in the quantities of soil-derived metal ions carried into Flenley's swamp sediment cores. For exam-ple, excavations on the Poike Peninsula show that crops were initially grownthere interspersed with palm trees left standing, so that their crowns couldshade and protect the soil and crops against hot sun, evaporation, wind, anddirect rain impacts. Clearance of the palms led to massive erosion thatburied ahu and buildings downhill with soil, and that forced the abandon-ment of Poike's fields around 1400. Once grassland had established itself onPoike, farming was resumed there around 1500, to be abandoned again acentury later in a second wave of erosion. Other damages to soil that re-sulted from deforestation and reduced crop yields included desiccation andnutrient leaching. Farmers found themselves without most of the wild plantleaves, fruit, and twigs that they had been using as compost.Those were the immediate consequences of deforestation and other hu-man environmental impacts. The further consequences start with starva-tion, a population crash, and a descent into cannibalism. Surviving islanders'accounts of starvation are graphically confirmed by the proliferation of littlestatues called moai kavakava, depicting starving people with hollowcheeks and protruding ribs. Captain Cook in 1774 described the islanders as"small, lean, timid, and miserable." Numbers of house sites in the coastallowlands, where almost everybody lived, declined by 70% from peak valuesaround 1400-1600 to the 1700s, suggesting a corresponding decline innumbers of people. In place of their former sources of wild meat, islandersturned to the largest hitherto unused source available to them: humans,whose bones became common not only in proper burials but also (crackedto extract the marrow) in late Easter Island garbage heaps. Oral traditions ofthe islanders are obsessed with cannibalism; the most inflammatory tauntthat could be snarled at an enemy was "The flesh of your mother sticks be-tween my teeth."Easter's chiefs and priests had previously justified their elite status byclaiming relationship to the gods, and by promising to deliver prosperityand bountiful harvests. They buttressed that ideology by monumental ar-chitecture and ceremonies designed to impress the masses, and made possi-ble by food surpluses extracted from the masses. As their promises werebeing proved increasingly hollow, the power of the chiefs and priests wasoverthrown around 1680 by military leaders called matatoa, and Easter'sformerly complexly integrated society collapsed in an epidemic of civil war.The obsidian spear-points (termed mata'a) from that era of fighting still lit-tered Easter in modern times. Commoners now builttheir huts in thecoastal zone, which had been previously reserved for the residences (harepaenga) of the elite. For safety, many people turned to living in caves thatwere enlarged by excavation and whose entrances were partly sealed to cre-ate a narrow tunnel for easier defense. Food remains, bone sewing needles,woodworking implements, and tools for repairing tapa cloth make clearthat the caves were being occupied on a long-term basis, not just as tempo-rary hiding places.What had failed, in the twilight of Easter's Polynesian society, was notonly the old political ideology but also the old religion, which became dis-carded along with the chiefs' power. Oral traditions record that the last ahuand moai were erected around 1620, and that Paro (the tallest statue) wasamong the last. The upland plantations whose elite-commandeered pro-duction fed the statue teams were progressively abandoned between 1600and 1680. That the sizes of statues had been increasing may reflect not onlyrival chiefs vying to outdo each other, but also more urgent appeals to an-cestors necessitated by the growing environmental crisis. Around 1680, atthe time of the military coup, rival clans switched from erecting increas-ingly large statues to throwing down one another's statues by toppling astatue forwards onto a slab placed so that the statue would fall on the slaband break. Thus, as we shall also see for the Anasazi and Maya in Chapters 4and 5, the collapse of Easter society followed swiftly upon the society'sreaching its peak of population, monument construction, and environmen-tal impact.We don't know how far the toppling had proceeded at the time of thefirst European visits, because Roggeveen in 1722 landed only briefly at a sin-gle site, and Gonzalez's Spanish expedition of 1770 wrote nothing abouttheir visit except in the ship's log. The first semi-adequate European de-scription was by Captain Cook in 1774, who remained for four days, sent adetachment to reconnoiter inland, and had the advantage of bringing aTahitian whose Polynesian language was sufficiently similar to that of EasterIslanders that he could converse with them. Cook commented on seeingstatues that had been thrown down, as well as others still erect. The last Eu-ropean mention of an erect statue was in 1838; none was reported as stand-ing in 1868. Traditions relate that the final statue to be toppled (around1840) was Paro, supposedly erected by a woman in honor of her husband,and thrown down by enemies of her family so as to break Paro at mid-body.Ahu themselves were desecrated by pulling out some of the fine slabs inorder to construct garden walls (manavai) next to the ahu, and by usingother slabs to create burial chambers in which to place dead bodies. As a re-sult, today the ahu that have not been restored (i.e., most of them) look atfirst sight like mere piles of boulders. As Jo Anne Van Tilburg, ClaudioCristino, Sonia Haoa, Barry Rolett, and I drove around Easter, saw ahu afterahu as a rubble pile with its broken statues, reflected on the enormous effortthat had been devoted for centuries to constructing the ahu and to carvingand transporting and erecting the moai, and then remembered that it wasthe islanders themselves who had destroyed their own ancestors' work, wewere filled with an overwhelming sense of tragedy.Easter Islanders' toppling of their ancestral moai reminds me of Rus-sians and Romanians toppling the statues of Stalin and Ceausescu when theCommunist governments of those countries collapsed. The islanders musthave been filled with pent-up anger at their leaders for a long time, as weknow that Russians and Romanians were. I wonder how many of the statueswere thrown down one by one at intervals, by particular enemies of astatue's owner, as described for Paro; and how many were instead destroyedin a quickly spreading paroxysm of anger and disillusionment, as took placeat the end of communism. I'm also reminded of a cultural tragedy and re-jection of religion described to me in 1965 at a New Guinea highland villagecalled Bomai, where the Christian missionary assigned to Bomai boasted tome with pride how one day he had called upon his new converts to collecttheir "pagan artifacts" (i.e., their cultural and artistic heritage) at the airstripand burn them—and how they obeyed. Perhaps Easter Island's matatoa is-sued a similar summons to their own followers.I don't want to portray social developments on Easter after 1680 aswholly negative and destructive. The survivors adapted as best they could,both in their subsistence and in their religion. Not only cannibalism butalso chicken houses underwent explosive growth after 1650; chickens hadaccounted for less than 0.1% of the animal bones in the oldest middensthat David Steadman, Patricia Vargas, and Claudio Cristino excavated atAnakena. The matatoa justified their military coup by adopting a religiouscult, based on the creator god Makemake, who had previously been just oneof Easter's pantheon of gods. The cult was centered at Orongo village on therim of Rano Kau caldera, overlooking the three largest offshore islets towhich nesting seabirds had become confined. The new religion developedits own new art styles, expressed especially in petroglyphs (rock carvings) ofwomen's genitals, birdmen, and birds (in order of decreasing frequency),carved not only on Orongo monuments but also on toppled moai andpukao elsewhere. Each year the Orongo cult organized a competition be-tween men to swim across the cold, shark-infested, one-mile-wide straitseparating the islets from Easter itself, to collect the first egg laid in that sea-son by Sooty Terns, to swim back to Easter with the unbroken egg, and to beanointed "Birdman of the year" for the following year. The last Orongoceremony took place in 1867 and was witnessed by Catholic missionaries,just as the residue of Easter Island society not already destroyed by the is-landers themselves was being destroyed by the outside world.The sad story of European impacts on Easter Islanders may be quickly sum-marized. After Captain Cook's brief sojourn in 1774, there was a steadytrickle of European visitors. As documented for Hawaii, Fiji, and manyother Pacific islands, they must be assumed to have introduced Europeandiseases and thereby to have killed many previously unexposed islanders,though our first specific mention of such an epidemic is of smallpoxaround 1836. Again as on other Pacific islands, "black-birding," the kidnap-ping of islanders to become laborers, began on Easter around 1805 and cli-maxed in 1862-63, the grimmest year of Easter's history, when two dozenPeruvian ships abducted about 1,500 people (half of the surviving popula-tion) and sold them at auction to work in Peru's guano mines and othermenial jobs. Most of those kidnapped died in captivity. Under internationalpressure, Peru repatriated a dozen surviving captives, who brought anothersmallpox epidemic to the island. Catholic missionaries took up residence in1864. By 1872 there were only 111 islanders left on Easter.European traders introduced sheep to Easter in the 1870s and claimedland ownership. In 1888 the Chilean government annexed Easter, which ef-fectively became a sheep ranch managed by a Chile-based Scottish com-pany. All islanders were confined to living in one village and to working forthe company, being paid in goods at the company store rather than in cash.A revolt by the islanders in 1914 was ended by the arrival of a Chilean war-ship. Grazing by the company's sheep, goats, and horses caused soil erosionand eliminated most of what had remained of the native vegetation, includ-ing the last surviving hauhau and toromiro individuals on Easter around1934. Not until 1966 did islanders become Chilean citizens. Today, islandersare undergoing a resurgence of cultural pride, and the economy is beingstimulated by the arrival of several airplane flights each week fromSantiagoand Tahiti by Chile's national airline, carrying visitors (like Barry Rolett andme) attracted by the famous statues. However, even a brief visit makes obvi-ous that tensions remain between islanders and mainland-born Chileans,who are now represented in roughly equal numbers on Easter.Easter Island's famous rongo-rongo writing system was undoubtedly in-vented by the islanders, but there is no evidence for its existence until itsfirst mention by the resident Catholic missionary in 1864. All 25 survivingobjects with writing appear to postdate European contact; some of them arepieces of foreign wood or a European oar, and some may have been manu-factured by islanders specifically to sell to representatives of Tahiti's Catholicbishop, who became interested in the writing and sought examples. In 1995linguist Steven Fischer announced a decipherment of rongo-rongo texts asprocreation chants, but his interpretation is debated by other scholars. MostEaster Island specialists, including Fischer, now conclude that the inventionof rongo-rongo was inspired by the islanders' first contact with writing dur-ing the Spanish landing of 1770, or else by the trauma of the 1862-63 Peru-vian slave raid that killed so many carriers of oral knowledge.In part because of this history of exploitation and oppression, there hasbeen resistance among both islanders and scholars to acknowledging thereality of self-inflicted environmental damage before Roggeveen's arrival in1722, despite all the detailed evidence that I have summarized. In essence,the islanders are saying, "Our ancestors would never have done that," whilevisiting scientists are saying, "Those nice people whom we have come tolove would never have done that." For example, Michel Orliac wrote aboutsimilar questions of environmental change in Tahiti, "... it is at least aslikely—if not more so—that environmental modifications originated innatural causes rather than in human activities. This is a much-debatedquestion (McFadgen 1985; Grant 1985; McGlone 1989) to which I do notclaim to bring a definitive solution, even if my affection for the Polynesiansincites me to choose natural actions [e.g., cyclones] to explain the damagessuffered by the environment." Three specific objections or alternative theo-ries have been raised.First, it has been suggested that Easter's deforested condition seen byRoggeveen in 1722 was not caused by the islanders in isolation but resultedin some unspecified way from disruption caused by unrecorded Europeanvisitors before Roggeveen. It is perfectly possible that there were indeed oneor more such unrecorded visits: many Spanish galleons were sailing acrossthe Pacific in the 1500s and 1600s, and the islanders' nonchalant, unafraid,curious reaction to Roggeveen does suggest prior experience of Europeans,rather than the shocked reaction expected for people who had been livingin total isolation and had assumed themselves to be the only humans in theworld. However, we have no specific knowledge of any pre-1722 visit, nor isit obvious how it would have triggered deforestation. Even before Magellanbecame the first European to cross the Pacific in 1521, abundant evidenceattests to massive human impacts on Easter: extinctions of all the land birdspecies, disappearance of porpoises and tuna from the diet, declines of for-est tree pollen in Flenley's sediment cores before 1300, deforestation of thePoike Peninsula by around 1400, lack of radiocarbon-dated palm nuts after1500, and so on.A second objection is that deforestation might instead have been dueto natural climate changes, such as droughts or El Nino episodes. It wouldnot surprise me at all if a contributing role of climate change does eventu-ally emerge for Easter, because we shall see that climatic downturns didexacerbate human environmental impacts by the Anasazi (Chapter 4),Maya (Chapter 5), Greenland Norse (Chapters 7 and 8), and probably manyother societies. At present, we lack information about climate changes onEaster in the relevant period of A.D. 900-1700: we don't know whether theclimate got drier and stormier and less favorable to forest survival (as pos-tulated by critics), or wetter and less stormy and more favorable to forestsurvival. But there seems to me to be compelling evidence against climatechange by itself having caused the deforestation and bird extinctions: thepalm trunk casts in Mt. Terevaka's lava flows prove that the giant palm hadalready survived on Easter for several hundred thousand years; and Flen-ley's sediment cores demonstrate pollen of the palm, tree daisies, toromiro,and half-a-dozen other tree species on Easter between 38,000 and 21,000years ago. Hence Easter's plants had already survived innumerable droughtsand El Nino events, making it unlikely that all those native tree species fi-nally chose a time coincidentally just after the arrival of those innocent hu-mans to drop dead simultaneously in response to yet another drought or ElNino event. In fact, Flenley's records show that a cool dry period on Easterbetween 26,000 and 12,000 years ago, more severe than any worldwide cooldry period in the last thousand years, merely caused Easter's trees at higherelevation to undergo a retreat to the lowlands, from which they subse-quently recovered.A third objection is that Easter Islanders surely wouldn't have been sofoolish as to cut down all their trees, when the consequences would havebeen so obvious to them. As Catherine Orliac expressed it," Why destroy aforest that one needs for his [i.e., the Easter Islanders'] material and spiri-tual survival?" This is indeed a key question, one that has nagged not onlyCatherine Orliac but also my University of California students, me, andeveryone else who has wondered about self-inflicted environmental dam-age. I have often asked myself, "What did the Easter Islander who cut downthe last palm tree say while he was doing it?" Like modern loggers, did heshout "Jobs, not trees!"? Or: "Technology will solve our problems, neverfear, we'll find a substitute for wood"? Or: "We don't have proof that therearen't palms somewhere else on Easter, we need more research, your pro-posed ban on logging is premature and driven by fear-mongering"? Similarquestions arise for every society that has inadvertently damaged its envi-ronment. When we return to this question in Chapter 14, we shall see thatthere is a whole series of reasons why societies nevertheless do make suchmistakes.Why Was Easter Fragile?We still have not faced the question why Easter Island ranks as such anextreme example of deforestation. After all, the Pacific encompasses thou-sands of inhabited islands, almost all of whose inhabitants were choppingdown trees, clearing gardens, burning firewood, building canoes, and usingwood and rope for houses and other things. Yet, among all those islands,only three in the Hawaiian Archipelago, all of them much drier thanEaster—the two islets of Necker and Nihoa, and the larger island ofNiihau—even approach Easter in degree of deforestation. Nihoa still sup-ports one species of large palm tree, and it is uncertain whether tiny Necker,with an area of barely forty acres, ever had trees. Why were Easter Islandersunique, or nearly so, in destroying every tree? The answer sometimes given,"because Easter's palm and toromiro were very slow-growing," fails to ex-plain why at least 19 other tree or plant species related to or the same asspecies still widespread on East Polynesian islands were eliminated onEaster but not on other islands. I suspect that this question lies behind thereluctance of Easter Islanders themselves and of some scientists to acceptthat the islanders caused the deforestation, because that conclusion seemsto imply that they were uniquely bad or improvident among Pacificpeoples.Barry Rolett and I were puzzled by that apparent uniqueness of Easter.Actually, it's just part of a broader puzzling question:why degree of defor-estation varies among Pacific islands in general. For example, Mangareva(to be discussed in the next chapter), most of the Cook and Austral Islands,and the leeward sides of the main Hawaiian and Fijian Islands were largelydeforested, though not completely as in the case of Easter. The Societies andMarquesas, and the windward sides of the main Hawaiian and Fijian Is-lands, supported primary forests at higher elevation and a mixture of sec-ondary forests, fernlands, and grasslands at low elevation. Tonga, Samoa,most of the Bismarcks and Solomons, and Makatea (the largest of theTuamotus) remained largely forested. How can all that variation beexplained?Barry began by combing through the journals of early European explor-ers of the Pacific, to locate descriptions of what the islands looked like then.That enabled him to extract the degree of deforestation on 81 islands as firstseen by Europeans—i.e., after centuries or millennia of impacts by native Pa-cific Islanders but before European impacts. For those same 81 islands, wethen tabulated values of nine physical factors whose interisland variationwe thought might contribute to explaining those different outcomes of de-forestation. Some trends immediately became obvious to us when we justeyeballed the data, but we ground the data through many statistical analysesin order to be able to put numbers on the trends.What Affects Deforestation on Pacific Islands?Deforestation is more severe on:dry islands than wet islands;cold high-latitude islands than warm equatorial islands;old volcanic islands than young volcanic islands;islands without aerial ash fallout than islands with it;islands far from Central Asia's dust plume than islands near it;islands without makatea than islands with it;low islands than high islands;remote islands than islands with near neighbors; andsmall islands than big islands.It turned out that all nine of the physical variables did contribute to theoutcome (see the table above). Most important were variations in rainfalland latitude: dry islands, and cooler islands farther from the equator (athigher latitude), ended up more deforested than did wetter equatorial is-lands. That was as we had expected: the rate of plant growth and of seedlingestablishment increases with rainfall and with temperature. When onechops trees down in a wet hot place like the New Guinea lowlands, within ayear new trees 20 feet tall have sprung up on the site, but tree growth ismuch slower in a cold dry desert. Hence regrowth can keep pace with mod-erate rates of cutting trees on wet hot islands, leaving the island in a steadystate of being largely tree-covered.Three other variables—island age, ash fallout, and dust fallout—had ef-fects that we hadn't anticipated, because we hadn't been familiar with thescientific literature on the maintenance of soil fertility. Old islands thathadn't experienced any volcanic activity for over a million years ended upmore deforested than young, recently active volcanic islands. That's becausesoil derived from fresh lava and ash contains nutrients that are necessary forplant growth, and that gradually become leached out by rain on older is-lands. One of the two main ways that those nutrients then become renewedon Pacific islands is by fallout of ash carried in the air from volcanic explo-sions. But the Pacific Ocean is divided by a line famous to geologists andknown as the Andesite Line. In the Southwest Pacific on the Asian side ofthat line, volcanoes blow out ash that may be wind-carried for hundreds ofmiles and that maintains the fertility even of islands (like New Caledonia)that have no volcanoes of their own. In the central and eastern Pacific be-yond the Andesite Line, the main aerial input of nutrients to renew soil fer-tility is instead in dust carried high in the atmosphere by winds from thesteppes of Central Asia. Hence islands east of the Andesite Line, and farfrom Asia's dust plume, ended up more deforested than islands within theAndesite Line or nearer to Asia.Another variable required consideration only for half a dozen islandsthat consist of the rock known as makatea—basically, a coral reef thrustinto the air by geological uplift. The name arises from the Tuamotu islandof Makatea, which consists largely of that rock. Makatea terrain is absolutehell to walk over; the deeply fissured, razor-sharp coral cuts one's boots,feet, and hands to shreds. When I first encountered makatea on Rennell Is-land in the Solomons, it took me 10 minutes to walk a hundred yards, and Iwas in constant terror of macerating my hands on a coral boulder if Itouched it while thoughtlessly extending my hands to maintain my bal-ance. Makatea can slice up stout modern boots within a few days of walk-ing. While Pacific Islanders somehow managed to get around on it in barefeet, even they had problems. No one who has endured the agony of walkingon makatea will be surprised that Pacific islands with makatea ended up lessdeforested than those without it.That leaves three variables with more complex effects: elevation, dis-tance, and area. High islands tended to become less deforested (even in theirlowlands) than low islands, because mountains generate clouds and rain,which descends to the lowlands as streams stimulating lowland plantgrowth by their water, by their transport of eroded nutrients, and by trans-port of atmospheric dust. The mountains themselves may remain forest-covered if they are too high or too steep for gardening. Remote islandsbecame more deforested than islands near neighbors—possibly because is-landers were more likely to stay home and do things impacting their ownenvironment than to spend time and energy visiting other islands to trade,raid, or settle. Big islands tended to become less deforested than small is-lands, for numerous reasons including lower perimeter/area ratios, hencefewer marine resources per person and lower population densities, morecenturies required to chop down the forest, and more areas unsuitable forgardening remaining.How does Easter rate according to these nine variables predisposing todeforestation? It has the third highest latitude, among the lowest rainfalls,the lowest volcanic ash fallout, the lowest Asian dust fallout, no makatea,and the second greatest distance from neighboring islands. It is among thelower and smaller of the 81 islands that Barry Rolett and I studied. All eightof those variables make Easter susceptible to deforestation. Easter's volca-noes are of moderate age (probably 200,000 to 600,000 years); Easter's PoikePeninsula, its oldest volcano, was the first part of Easter to become defor-ested and exhibits the worst soil erosion today. Combining the effects of allthose variables, Barry's and my statistical model predicted that Easter, Ni-hoa, and Necker should be the worst deforested Pacific islands. That agreeswith what actually happened: Nihoa and Necker ended up with no humanleft alive and with only one tree species standing (Nihoa's palm), whileEaster ended up with no tree species standing and with about 90% of itsformer population gone.In short, the reason for Easter's unusually severe degree of deforestationisn't that those seemingly nice people really were unusually bad or improvi-dent. Instead, they had the misfortune to be living in one of the most fragileenvironments, at the highest risk for deforestation, of any Pacific people.For Easter Island, more than for any other society discussed in this book, wecan specify in detail the factors underlying environmental fragility.Easter's isolation makes it the clearest example of a society that destroyeditself by overexploiting its own resources. If we return to our five-pointchecklist of factors to be considered in connection with environmental col-lapses, two of those factors—attacks by neighboring enemy societies, andloss of support from neighboring friendly societies—played no roleinEaster's collapse, because there is no evidence that there were any enemiesor friends in contact with Easter Island society after its founding. Even if itturns out that some canoes did arrive subsequently, such contacts could nothave been on a large enough scale to constitute either dangerous attacks orimportant support. For a role of a third factor, climate change, we also haveno evidence at present, though it may emerge in the future. That leaves uswith just two main sets of factors behind Easter's collapse: human environ-mental impacts, especially deforestation and destruction of bird popula-tions; and the political, social, and religious factors behind the impacts,such as the impossibility of emigration as an escape valve because of Easter'sisolation, a focus on statue construction for reasons already discussed, andcompetition between clans and chiefs driving the erection of bigger statuesrequiring more wood, rope, and food.The Easter Islanders' isolation probably also explains why I have foundthat their collapse, more than the collapse of any other pre-industrial soci-ety, haunts my readers and students. The parallels between Easter Islandand the whole modern world are chillingly obvious. Thanks to globaliza-tion, international trade, jet planes, and the Internet, all countries on Earthtoday share resources and affect each other, just as did Easter's dozen clans.Polynesian Easter Island was as isolated in the Pacific Ocean as the Earth istoday in space. When the Easter Islanders got into difficulties, there was no-where to which they could flee, nor to which they could turn for help; norshall we modern Earthlings have recourse elsewhere if our troubles in-crease. Those are the reasons why people see the collapse of Easter Islandsociety as a metaphor, a worst-case scenario, for what may lie ahead of us inour own future.Of course, the metaphor is imperfect. Our situation today differs in im-portant respects from that of Easter Islanders in the 17th century. Some ofthose differences increase the danger for us: for instance, if mere thousandsof Easter Islanders with just stone tools and their own muscle power suf-ficed to destroy their environment and thereby destroyed their society, howcan billions of people with metal tools and machine power now fail to doworse? But there are also differences in our favor, differences to which weshall return in the last chapter of this book.C H A P T E R 3The Last People Alive: Pitcairnand Henderson IslandsPitcairn before the Bounty m Three dissimilar islands Trade Themovie's ending many centuries ago, immigrants came to a fertile land blessed withapparently inexhaustible natural resources. While the land lacked afew raw materials useful for industry, those materials were readilyobtained by overseas trade with poorer lands that happened to have de-posits of them. For a time, all the lands prospered, and their populationsmultiplied.But the population of the rich land eventually multiplied beyond thenumbers that even its abundant resources could support. As its forests werefelled and its soils eroded, its agricultural productivity was no longer suffi-cient to generate export surpluses, build ships, or even to nourish its ownpopulation. With that decline of trade, shortages of the imported raw mate-rials developed. Civil war spread, as established political institutions wereoverthrown by a kaleidoscopically changing succession of local militaryleaders. The starving populace of the rich land survived by turning to can-nibalism. Their former overseas trade partners met an even worse fate: de-prived of the imports on which they had depended, they in turn ravagedtheir own environments until no one was left alive.Does this grim scenario represent the future of the United States andour trade partners? We don't know yet, but the scenario has already playeditself out on three tropical Pacific islands. One of them, Pitcairn Island, isfamous as the "uninhabited" island to which the mutineers from the H.M.S.Bounty fled in 1790. They chose Pitcairn because it was indeed uninhabitedat that time, remote, and hence offered a hiding place from the vengefulBritish navy searching for them. But the mutineers did find temple plat-forms, petroglyphs, and stone tools giving mute evidence that Pitcairn hadformerly supported an ancient Polynesian population. East of Pitcairn, aneven more remote island named Henderson remains uninhabited to thisMday. Even now, Pitcairn and Henderson are among the most inaccessible islandsin the world, without any air or scheduled sea traffic, and visited only by theoccasional yacht or cruise ship. Yet Henderson, too, bears abundant marks of aformer Polynesian population. What happened to those original PitcairnIslanders, and to their vanished cousins on Henderson?The romance and mystery of the H.M.S. Bounty mutineers on Pitcairn, retoldin many books and films, are matched by the mysterious earlier ends of thesetwo populations. Basic information about them has at last emerged from recentexcavations by Marshall Weisler, an archaeologist at the University of Otago inNew Zealand, who spent eight months on those lonely outposts. The fates of thefirst Pitcairners and the Henderson Islanders prove to have been linked to aslowly unfolding environmental catastrophe hundreds of miles overseas on theirmore populous island trading partner, Man-gareva, whose population survived atthe cost of a drastically lowered standard of living. Thus, just as Easter Islandoffered us our clearest example of a collapse due to human environmentalimpacts with a minimum of other complicating factors, Pitcairn and HendersonIslands furnish our clearest examples of collapses triggered by the breakdown ofan environmentally damaged trade partner: a preview of risks already developingtoday in association with modern globalization. Environmental damage onPitcairn and Henderson themselves also contributed to the collapses there, butthere is no evidence for roles of climate change or of enemies.Mangareva, Pitcairn, and Henderson are the sole habitable islands in the areaknown as Southeast Polynesia, which otherwise includes just a few low atollssupporting only temporary populations or visitors but no permanent populations.These three habitable islands were settled sometime around A.D. 800, as part ofthe eastwards Polynesian expansion explained in the preceding chapter. EvenMangareva, the westernmost of the three islands and hence the one closest topreviously settled parts of Polynesia, lies about a thousand miles beyond thenearest large high islands, such as the Societies (including Tahiti) to the westand the Marquesas to the northwest. The Societies and Marquesas in turn, whichare the largest and most populous islands in East Polynesia, lie more than athousand miles east of the nearest high islands of West Polynesia and may nothave been colonized until perhaps nearly 2,000 years after West Polynesia'ssettlement. Thus, Mangareva and its neighbors were isolated outliers even withinPolynesia's more remote eastern half. They were probably occupied from theMarquesas orSocieties during the same colonizing push that reached the even more re-mote Hawaiian Islands and Easter, and that completed the settlement ofPolynesia (maps, pp. 84-85 and this page).Of those three habitable islands of Southeast Polynesia, the one capableof supporting by far the largest human population, and most abundantlyendowed with natural resources important to humans, was Mangareva. Itconsists of a large lagoon 15 miles in diameter, sheltered by an outer reef,and containing two dozen extinct volcanic islands and a few coral atollswith a total land area of 10 square miles. The lagoon, its reefs, and the oceanoutside the lagoon teem with fish and shellfish. Especially valuable amongthe species of shellfish is the black-lipped pearl oyster, a very large oyster ofwhich the lagoon offeredvirtually inexhaustible quantities to Polynesiansettlers, and which is the species used today to raise the famous black cul-tured pearls. In addition to the oyster itself being edible, its thick shell, up toeight inches long, was an ideal raw material that Polynesians carved intofishhooks, vegetable peelers and graters, and ornaments.The higher islands of Mangareva's lagoon received enough rain to havesprings and intermittent streams, and were originally forested. In the nar-row band of flat land around the coasts, the Polynesian colonists built theirsettlements. On the slopes behind the villages they grew crops such as sweetpotato and yams; terraced slopes and flats below the springs were planted intaro, irrigated by spring water; and higher elevations were planted in treecrops such as breadfruit and bananas. In this way, farming and fishing andgathering of shellfish would have been able to support a human populationof several thousand on Mangareva, more than 10 times the likely combinedpopulations of Pitcairn and Henderson in ancient Polynesian times.From a Polynesian perspective, Mangareva's most significant drawbackwas its lack of high-quality stone for making adzes and other stone tools.(That's as if the United States contained all important natural resources ex-cept high-grade iron deposits.) The coral atolls in Mangareva lagoon hadno good raw stone at all, and even the volcanic islands offered only rela-tively coarse-grained basalt. That was adequate for building houses and gar-den walls, using as oven stones, and fashioning into canoe anchors and foodpounders and other crude tools, but coarse-grained basalt yielded only infe-rior adzes.Fortunately, that deficiency was spectacularly remedied on Pitcairn, themuch smaller (2V2 square miles) and steeper extinct volcanic island lying300 miles southeast of Mangareva. Imagine the excitement when the firstcanoeload of Mangarevans discovered Pitcairn after several days' travel onopen ocean, landed at its only feasible beach, scrambled up the steep slopes,and came upon Down Rope Quarry, Southeast Polynesia's sole useable lodeof volcanic glass, whose flakes could serve as sharp tools for fine cuttingtasks—the Polynesian equivalent of scissors and scalpels. Their excitementwould have turned to ecstasy when, barely a mile farther west along thecoast, they discovered the Tautama lode of fine-grained basalt, which be-came Southeast Polynesia's biggest quarry for making adzes.In other respects, Pitcairn offered much more limited opportunitiesthan did Mangareva. It did have intermittent streams, and its forests in-cluded trees large enough to fashion into hulls of outrigger canoes. But Pit-cairn's steepness and small total area meant that the area of level plateausuitable for agriculture was very small. An equally serious drawback is thatPitcairn's coastline lacks a reef, and the surrounding sea bottom falls offsteeply, with the result that fishing and the search for shellfish are much lessrewarding than on Mangareva. In particular, Pitcairn has no beds of thoseblack-lipped pearl oysters so useful for eating and tool-making. Hence thetotal population of Pitcairn in Polynesian times was probably not muchgreater than a hundred people. The descendants of the Bounty mutineersand their Polynesian companions living on Pitcairn today number only 52.When their number climbed from the original band of 27 settlers in 1790 to194 descendants in the year 1856, that population overtaxed Pitcairn's agri-cultural potential, and much of the population had to be evacuated by theBritish government to distant Norfolk Island.The remaining habitable island of Southeast Polynesia, Henderson, isthe largest (14 square miles) but is also the most remote (100 miles north-east of Pitcairn, 400 miles east of Mangareva) and the most marginal forhuman existence. Unlike Mangareva or Pitcairn, Henderson is not volcanicbut is in effect a coral reef that geological processes thrust up 100 feet abovesea level. Hence Henderson is devoid of basalt or other rocks suitable fortool-making. That's a severe limitation for a society of stone tool makers.An additional severe limitation for any humans is that Henderson has nostreams or reliable freshwater sources, because the island consists of porouslimestone. At best, for a few days after the unpredictable arrivals of rain, wa-ter drips from the roofs of caves, and puddles of water can be found on theground. There is also a freshwater spring that bubbles up in the ocean about20 feet offshore. During Marshall Weisler's months on Henderson, he foundobtaining drinking water even with modern tarpaulins to catch the rain aconstant effort, and most of his cooking and all of his washing and bathinghad to be carried out with saltwater.Even soil on Henderson is confined to small pockets between the lime-stone. The island's tallest trees are only about 50 feet high and not bigenough to fashion into canoe hulls. The resulting stunted forest and thickundergrowth are so dense that they require a machete to penetrate them.Henderson's beaches are narrow and confined to the north end; its southcoast consists of vertical cliffs where it is impossible to land a boat; and thesouth end of the island is a makatea landscape thrown into alternating rowsof razor-sharp limestone ridges and fissures. That south end has beenreached only three times by groups of Europeans, one of them Weisler'sgroup. It took Weisler, wearing hiking boots, five hours to cover the fivemiles from Henderson's north coast to its south coast—where he promptlydiscovered a rock shelter formerly occupied by barefoot Polynesians.Offsetting these fearsome disadvantages, Henderson does have attrac-tions. In the reef and shallow waters nearby live lobsters, crabs, octopus, anda limited variety of fish and shellfish—unfortunately, not including black-lipped pearl oyster. On Henderson is Southeast Polynesia's sole known tur-tle nesting beach, where green turtles come ashore to lay eggs betweenJanuary and March of each year. Henderson formerly supported at least 17species of breeding seabirds, including petrel colonies possibly as large asmillions of birds, whose adults and chicks would have been easy to catch onthe nest—enough for a population of a hundred people each to eat one birdevery day of the year without endangering the colonies' survival. The islandwas also home to nine species of resident land birds, five of them flightlessor weak fliers and hence easy to catch, including three species of large pi-geons that would have been especially delectable.All those features would have made Henderson a great place for an after-noon picnic ashore, or for a short vacation to glut yourself on seafood andbirds and turtles—but a risky and marginal home in which to try to eke outa permanent existence. Weisler's excavations nevertheless showed, to thesurprise of anyone who has seen or heard of Henderson, that the island didevidently support a permanent tiny population, possibly comprising a fewdozen people who went to extreme effort in order to survive. Proof of theirformer presence is provided by 98 human bones and teeth representing atleast 10 adults (both men and women, some of them over 40 years old), sixteenaged boys and girls, and four children in the age range of 5 to 10 years.The children's bones in particular suggest a resident population; modernPitcairn Islanders usually don't take young children when they visit Hen-derson to collect wood or seafood.Further evidence of human use is a huge buried midden, one of thelargest known from Southeast Polynesia, running for 300 yards in lengthand 30 yards in width along the north-coast beach facing the only passagethrough Henderson's fringing reef. Among the midden's garbage left behindfrom generations of people feasting, and identified in small test pits exca-vated by Weisler and his colleagues, are enormous quantities of fish bones(14,751tralians, do indeed seize on the discoveries to advance that argument today.Not only indigenous peoples, but also some anthropologists and archaeolo-gists who study them and identify with them, view the recent supposed dis-coveries as racist lies.Some of the indigenous peoples and the anthropologists identifyingwith them go to the opposite extreme. They insist that past indigenous peo-ples were (and modern ones still are) gentle and ecologically wise stewardsof their environments, intimately knew and respected Nature, innocentlylived in a virtual Garden of Eden, and could never have done all those badthings. As a New Guinea hunter once told me, "If one day I succeed inshooting a big pigeon in one direction from our village, I wait a week beforehunting pigeons again, and then I go out in the opposite direction from thevillage." Only those evil modern First World inhabitants are ignorant of Na-ture, don't respect the environment, and destroy it.In fact, both extreme sides in this controversy—-the racists and the be-lievers in a past Eden—are committing the error of viewing past indigenouspeoples as fundamentally different from (whether inferior to or superior to)modern First World peoples. Managing environmental resources sustain-ably has always been difficult, ever since Homo sapiens developed moderninventiveness, efficiency, and hunting skills by around 50,000 years ago.Beginning with the first human colonization of the Australian continentaround 46,000 years ago, and the subsequent prompt extinction of most ofAustralia's former giant marsupials and other large animals, every humancolonization of a land mass formerly lacking humans—whether of Aus-tralia, North America, South America, Madagascar, the Mediterranean is-lands, or Hawaii and New Zealand and dozens of other Pacific islands—hasbeen followed by a wave of extinction of large animals that had evolvedwithout fear of humans and were easy to kill, or else succumbed to human-associated habitat changes, introduced pest species, and diseases. Any peo-ple can fall into the trap of overexploiting environmental resources, becauseof ubiquitous problems that we shall consider later in this book: that the re-sources initially seem inexhaustibly abundant; that signs of their incipientdepletion become masked by normal fluctuations in resource levels be-tween years or decades; that it's difficult to get people to agree on exercisingrestraint in harvesting a shared resource (the so-called tragedy of the com-mons, to be discussed in later chapters); and that the complexity of ecosys-tems often makes the consequences of some human-caused perturbationvirtually impossible to predict even for a professional ecologist. Environ-mental problems that are hard to manage today were surely even harder tomanage in the past. Especially for past non-literate peoples who couldn'tread case studies of societal collapses, ecological damage constituted atragic, unforeseen, unintended consequence of their best efforts, rather thanmorally culpable blind or conscious selfishness. The societies that ended upcollapsing were (like the Maya) among the most creative and (for a time)advanced and successful of their times, rather than stupid and primitive.Past peoples were neither ignorant bad managers who deserved to be ex-terminated or dispossessed, nor all-knowing conscientious environmental-ists who solved problems that we can't solve today. They were people like us,facing problems broadly similar to those that we now face. They were proneeither to succeed or to fail, depending on circumstances similar to thosemaking us prone to succeed or to fail today. Yes, there are differences be-tween the situation we face today and that faced by past peoples, but thereare still enough similarities for us to be able to learn from the past.Above all, it seems to me wrongheaded and dangerous to invoke histori-cal assumptions about environmental practices of native peoples in order tojustify treating them fairly. In many or most cases, historians and archaeolo-gists have been uncovering overwhelming evidence that this assumption(about Eden-like environmentalism) is wrong. By invoking this assumptionto justify fair treatment of native peoples, we imply that it would be OK tomistreat them if that assumption could be refuted. In fact, the case againstmistreating them isn't based on any historical assumption about their envi-ronmental practices: it's based on a moral principle, namely, that it is mor-ally wrong for one people to dispossess, subjugate, or exterminate anotherpeople.That's the controversy about past ecological collapses. As for the complica-tions, of course it's not true that all societies are doomed to collapse becauseof environmental damage: in the past some societies did while others didn't;the real question is why only some societies proved fragile, and what distin-guished those that collapsed from those that didn't. Some societies that Ishall discuss, such as the Icelanders and Tikopians, succeeded in solving ex-tremely difficult environmental problems, have thereby been able to persistfor a long time, and are still going strong today. For example, when Norwe-gian colonists of Iceland first encountered an environment superficiallysimilar to that of Norway but in reality very different, they inadvertently de-stroyed much of Iceland's topsoil and most of its forests. Iceland for a longtime was Europe's poorest and most ecologically ravaged country. However,Icelanders eventually learned from experience, adopted rigorous measuresof environmental protection, and now enjoy one of the highest per-capitanational average incomes in the world. Tikopia Islanders inhabit a tinyisland so far from any neighbors that they were forced to become self-sufficient in almost everything, but they micromanaged their resources andregulated their population size so carefully that their island is still produc-tive after 3,000 years of human occupation. Thus, this book is not an unin-terrupted series of depressing stories of failure, but also includes successstories inspiring imitation and optimism.In addition, I don't know of any case in which a society's collapse canbe attributed solely to environmental damage: there are always other con-tributing factors. When I began to plan this book, I didn't appreciate thosecomplications, and I naively thought that the book would just be aboutenvironmental damage. Eventually, I arrived at a five-point frameworkof possible contributing factors that I now consider in trying to under-stand any putative environmental collapse. Four of those sets of factors—environmental damage, climate change, hostile neighbors, and friendlytrade partners—may or may not prove significant for a particular society.The fifth set of factors—the society's responses to its environmentalproblems—always proves significant. Let's consider these five sets of factorsone by one, in a sequence not implying any primacy of cause but just conve-nience of presentation.A first set of factors involves damage that people inadvertently inflict ontheir environment, as already discussed. The extent and reversibility of thatdamage depend partly on properties of people (e.g., how many trees theycut down per acre per year), and partly on properties of the environment(e.g., properties determining how many seedlings germinate per acre, andhow rapidly saplings grow, per year). Those environmental properties arereferred to either as fragility (susceptibility to damage) or as resilience (po-tential for recovery from damage), and one can talk separately of the fragilityor resilience of an area's forests, its soils, its fish populations, and so on.Hence the reasons why only certain societies suffered environmental col-lapses might in principle involve either exceptional imprudence of theirpeople, exceptional fragility of some aspects of their environment, or both.A next consideration in my five-pointfish bones in just two-thirds of a cubic yard of sand tested!), plus42,213 bird bones comprising tens of thousands of bones of seabirds (espe-cially petrels, terns, and tropicbirds) and thousands of bones of land birds(especially the flightless pigeons, rail, and sandpiper). When one extrapo-lates from the number of bones in Weisler's small test pits to the likely num-ber in the whole midden, one calculates that Henderson Islanders musthave disposed of the remains of tens of millions of fish and birds over thecenturies. The oldest human-associated radiocarbon date on Henderson isfrom that midden, and the next-oldest date is from the turtle nesting beachon the northeast coast, implying that people settled first in those areaswhere they could glut themselves on wild-caught food.Where could people live on an island that is nothing more than an up-lifted coral reef covered with low trees? Henderson is unique among islandsinhabited or formerly inhabited by Polynesians in its almost-complete lackof evidence for buildings, such as the usual houses and temples. There areonly three signs of any construction: a stone pavement and post holes in themidden, suggesting the foundations of a house or shelter; one small lowwall for protection against the wind; and a few slabs of beach rock for a bur-ial vault. Instead, literally every cave and rock shelter near the coast andwith a flat floor and accessible opening—even small recesses only threeyards wide and two yards deep, barely large enough for a few people to seekprotection from the sun—contained debris testifying to former humanhabitation. Weisler found 18 such shelters, of which 15 were on the heavilyused north, northeast, and northwest coasts near the only beaches, and theother three (all of them very cramped) were on the eastern or southerncliffs. Because Henderson is small enough that Weisler was able to surveyessentially the entire coast, the 18 caves and rock shelters, plus one shelteron the north beach, probably constitute all the "dwellings" of Henderson'spopulation.Charcoal, piles of stones, and relict stands of crop plants showed that thenortheast part of the island had been burned and laboriously converted togarden patches where crops could be planted in natural pockets of soil, ex-tended by piling surface stones into mounds. Among the Polynesian cropsand useful plants that were introduced intentionally by the settlers, and thathave been identified in Henderson archaeological sites or that still growwild on Henderson today, are coconuts, bananas, swamp taro, possibly taroitself, several species of timber trees, candlenut trees whose nut husks areburned for illumination, hibiscus trees yielding fiber for making rope, andthe ti shrub. The latter's sugary roots serve usually just as an emergencyfood supply elsewhere in Polynesia but were evidently a staple vegetablefood on Henderson. Ti leaves could be used to make clothing, house thatch-ing, and food wrappings. All of those sugary and starchy crops add up to ahigh-carbohydrate diet, which may explain why the teeth and jaws of Hen-derson Islanders that Weisler found exhibit enough signs of periodontaldisease, tooth wear, and tooth loss to give nightmares to a dentist. Most ofthe islanders' protein would have come from the wild birds and seafood, butfinds of a couple of pig bones show that they kept or brought pigs at leastoccasionally.Thus, Southeast Polynesia presented colonists with only a few potentiallylabitable islands. Mangareva, the one capable of supporting the largestcopulation, was largely self-sufficient in the necessities for Polynesian life,except for lacking high-quality stone. Of the other two islands, Pitcairn wasso small, Henderson so ecologically marginal, that each could support onlya tiny population unable to constitute a viable human society in the longrun. Both were also deficient in important resources—Henderson so muchso that we moderns, who wouldn't dream of going there even for a weekendwithout a full tool chest, drinking water, and food other than seafood, findit mind-boggling that Polynesians managed to survive there as residents.But both Pitcairn and Henderson offered compensating attractions to Poly-nesians: high-quality stone on the former, abundant seafood and birds onthe latter.Weisler's archaeological excavations uncovered extensive evidence oftrade among all three islands, whereby each island's deficiencies were filledby the other islands' surpluses. Trade objects, even those (such as ones ofstone) lacking organic carbon suitable for radiocarbon dating, can still bedated by radiocarbon measurements on charcoal excavated from the samearchaeological layer. In that way, Weisler established that trade began at leastby the year A.D. 1000, probably simultaneously with the first settlement byhumans, and continued for many centuries. Numerous objects excavated atWeisler's sites on Henderson could immediately be identified as imports be-cause they were made from materials foreign to Henderson: oyster shellfishhooks and vegetable peelers, volcanic glass cutting tools, and basaltadzes and oven stones.Where did those imports come from? A reasonable guess is that the oys-ter shell for fishhooks came from Mangareva, because oysters are abundantthere but absent on Pitcairn as well as on Henderson, and other islands withoyster beds are much more distant than Mangareva. A few oyster shell arti-facts have also been found on Pitcairn and are similarly presumed to havecome from Mangareva. But it is a much more difficult problem to identifyorigins of the volcanic stone artifacts found on Henderson, because bothMangareva and Pitcairn, as well as many other distant Polynesian islands,have volcanic sources.Hence Weisler developed or adapted techniques for discriminatingamong volcanic stones from different sources. Volcanoes spew out manydifferent types of lava, of which basalt (the category of volcanic stone oc-curring on Mangareva and Pitcairn) is defined by its chemical compositionand color. However, basalts from different islands, and often even from dif-ferent quarries on the same island, differ from each other in finer details ofchemical composition, such as their relative content of major elements (likesilicon and aluminum) and minor elements (like niobium and zirconium).An even finer discriminating detail is that the element lead occurs naturallyas several isotopes (i.e., several forms differing slightly in atomic weight),whose proportions also differ from one basalt source to another. To a geolo-gist, all these details of composition constitute a fingerprint that may allowone to identify a stone tool as coming from one particular island or quarry.Weisler analyzed the chemical composition and, with a colleague, thelead isotope ratios in dozens of stone tools and stone fragments (possiblybroken off in the course of preparing or repairing stone tools) that he hadexcavated from dated layers of archaeological sites on Henderson. For com-parison, he analyzed volcanic rocks from quarries and rock outcroppingson Mangareva and Pitcairn, the most likely sources of rock imported toHenderson. Just to be sure, he also analyzed volcanic rocks from Polynesianislands that were much more distant and hence less likely to have served assources of Henderson imports, including Hawaii, Easter, Marquesas, Soci-eties, and Samoa.The conclusions emerging from these analyses were unequivocal. All an-alyzed pieces of volcanic glass found on Henderson originated at the DownRope quarry on Pitcairn. That conclusion had already been suggested by vi-sual inspection of the pieces, even before chemical analysis, because Pitcairnvolcanic glass is colored so distinctively with black and gray patches. Mostof Henderson's basalt adzes, and its basalt flakes likely to have resulted fromadze-making, also originated from Pitcairn, but some came from Man-gareva. On Mangareva itself, although farfewer searches have been madefor stone artifacts than on Henderson, some adzes were also evidently madefrom Pitcairn basalt, imported presumably because of its superiority toMangareva's own basalt. Conversely, of the vesicular basalt stones excavatedon Henderson, most came from Mangareva, but a minority were from Pit-cairn. Such stones were regularly used throughout Polynesia as oven stones,to be heated in a fire for cooking, much like the charcoal bricks used inmodern barbecues. Many of those putative oven stones were found in cook-ing pits on Henderson and showed signs of having been heated, confirmingtheir surmised function.In short, archaeological studies have now documented a former flour-ishing trade in raw materials and possibly also in finished tools: in oystershell, from Mangareva to Pitcairn and Henderson; in volcanic glass, fromPitcairn to Henderson; and in basalt, from Pitcairn to Mangareva and Hen-derson, and from Mangareva to Henderson. In addition, Polynesia's pigsand its bananas, taro, and other main crops are species that did not occuron Polynesian islands before humans arrived. If Mangareva was settled be-fore Pitcairn and Henderson, as seems likely because Mangareva is the clos-est of the three to other Polynesian islands, then trade from Mangarevaprobably also brought the indispensable crops and pigs to Pitcairn andHenderson. Especially at the time when Mangareva's colonies on Pitcairnand Henderson were being founded, the canoes bringing imports fromMangareva represented an umbilical cord essential for populating andstocking the new colonies, in addition to their later role as a permanentlifeline.As for what products Henderson exported to Pitcairn and Mangareva inreturn, we can only guess. They must have been perishable items unlikely tosurvive in Pitcairn and Mangareva archaeological sites, since Hendersonlacks stones or shells worth exporting. One plausible candidate is live seaturtles, which today breed in Southeast Polynesia only on Henderson, andwhich throughout Polynesia were prized as a prestigious luxury food con-sumed mainly by chiefs—like truffles and caviar nowadays. A second candi-date is red feathers from Henderson's parrot, fruit dove, and red-tailedtropicbird, red feathers being another prestigious luxury item used for or-naments and feather cloaks in Polynesia, analogous to gold and sable furtoday.However, then as now, exchanges of raw materials, manufactured items,and luxuries would not have been the sole motive for transoceanic tradeand travel. Even after Pitcairn's and Henderson's populations had grown totheir maximum possible size, their numbers—about a hundred and a fewdozen individuals respectively—were so low that people of marriageableage would have found few potential partners on the island, and most ofthose partners would have been close relatives subject to incest taboos.Hence exchanges of marriage partners would have been an additional im-portant function of the trade with Mangareva. It would also have servedto bring skilled craftspeople with technical skills from Mangareva's largepopulation to Pitcairn and Henderson, and to reimport crops that bychance had died out in Pitcairn's and Henderson's small cultivable areas. Inthe same way, more recently the supply fleets from Europe were essentialnot only for populating and stocking but also maintaining Europe's over-seas colonies in America and Australia, which required a long time to de-velop even rudiments of self-sufficiency.From the perspective of Mangarevans and Pitcairn Islanders, therewould have been still another likely function of the trade with Henderson.The journey from Mangareva to Henderson would take four or five days byPolynesian sailing canoes; from Pitcairn to Henderson, about one day. Myown perspective on sea journeys in Pacific native canoes is based on muchbriefer voyages, which left me constantly terrified of the canoe's capsizing orbreaking up and in one case nearly cost me my life. That makes the thoughtof a several-day canoe voyage across open ocean intolerable to me, some-thing that only a desperate need to save my life could induce me to under-take. But to modern Pacific seafaring peoples, who sail their canoes five daysjust to buy cigarettes, the journeys are part of normal life. For the formerPolynesian inhabitants of Mangareva or Pitcairn, a visit to Henderson for aweek would have been a wonderful picnic, a chance to feast on nesting tur-tles and their eggs and on Henderson's millions of nesting seabirds. To Pit-cairn Islanders in particular, living on an island without reefs or calminshore waters or rich shellfish beds, Henderson would also have been at-tractive for fish, shellfish, and just for the chance to hang out on the beach.For the same reason, the descendants of the Bounty mutineers today, boredwith their tiny island prison, jump at the chance of a "vacation" on thebeach of a coral atoll a few hundred miles distant.Mangareva, it turns out, was the geographic hub of a much larger tradenetwork, of which the ocean journey to Pitcairn and Henderson a few hun-dred miles to the southeast was the shortest spoke. The longer spokes, ofabout a thousand miles each, connected Mangareva to the Marquesas tothe north-northwest, to the Societies to the west-northwest, and possiblyto the Australs due west. The dozens of low coral atolls of the TuamotuArchipelago offered small intermediate stepping-stones for breaking upthese journeys. Just as Mangareva's population of several thousand peopledwarfed that of Pitcairn and Henderson, the populations of the Societiesand Marquesas (around a hundred thousand people each) dwarfed that ofMangareva.Hard evidence for this larger trade network emerged in the course ofWeisler's chemical studies of basalt, when he had the good fortune to iden-tify two adzes of basalt originating from a Marquesas quarry and one adzefrom a Societies quarry among 19 analyzed adzes collected on Mangareva.Other evidence comes from tools whose styles vary from island to island,such as adzes, axes, fishhooks, octopus lures, harpoons, and files. Similari-ties of styles between islands, and appearances of examples of one island'stype of tool on another island, attest to trade especially between the Mar-quesas and Mangareva, with an accumulation of Marquesas-style tools onMangareva around A.D. 1100-1300 suggesting a peak in interisland voyag-ing then. Still further evidence comes from studies by the linguist StevenFischer, who concludes that the Mangarevan language as known in recenttimes is descended from the language originally brought to Mangareva byits first settlers and then heavily modified by subsequent contact with thelanguage of the southeastern Marquesas (the portion of the MarquesasArchipelago closest to Mangareva).As for the functions of all that trade and contact in the larger network,one was certainly economic, just as in the smaller Mangareva/Pitcairn/Henderson network, because the networks' archipelagoes complementedone another in resources. The Marquesas were the "motherland," with a bigland area and human population and one good basalt quarry, but poor ma-rine resources because there were no lagoons or fringing reefs. Mangareva, a"second motherland," boasted a huge and rich lagoon, offset by a small landarea and population and inferior stone. Mangareva's daughter colonies onPitcairn and Henderson had the drawbacks of a tiny land area and popula-tion but great stone on Pitcairn and great feasting on Henderson. Finally,the Tuamotu Archipelago offered only a small land area and no stone at all,but good seafood and a convenient stepping-stone location.Trade within Southeast Polynesia continued from about A.D. 1000 to 1450,as gauged by artifacts in radiocarbon-dated archaeological layers on Hen-derson. But by A.D. 1500, the trade had stopped, both in Southeast Polynesiaand along the other spokes radiating from Mangareva's hub. Thoselater ar-chaeological layers on Henderson contain no more imported Mangarevaoyster shell, no more Pitcairn volcanic glass, no more Pitcairn fine-grainedbasalt for cutting tools, and no more Mangareva or Pitcairn basalt ovenstone. Apparently the canoes were no longer arriving from either Man-gareva or Pitcairn. Because trees on Henderson itself are too small to makecanoes, Henderson's population of a few dozen was now trapped on one ofthe most remote, most daunting islands in the world. Henderson Islandersconfronted a problem that seems insoluble to us: how to survive on a raisedlimestone reef without any metal, without stones other than limestone, andwithout imports of any type.They survived in ways that strike me as a mixture of ingenious, desper-ate, and pathetic. For the raw material of adzes, in place of stone, theyturned to shells of giant clams. For awls to punch holes, they fell back on birdbones. For oven stones, they turned to limestone or coral or giant clamshell,all of which are inferior to basalt because they retain heat for less time, tendto crack after heating, and cannot be reused as often. They now madetheir fishhooks out of purse shell, which is much smaller than black-lippedpearl oyster shell, so that it yields only one hook per shell (instead of adozen hooks from an oyster shell) and restricts the types of hooks that canbe fashioned.Radiocarbon dates suggest that, struggling on in this way, Henderson'spopulation of originally a few dozen people survived for several genera-tions, possibly a century or more, after all contact with Mangareva and Pit-cairn was cut. But by A.D. 1606, the year of Henderson's "discovery" byEuropeans, when a boat from a passing Spanish ship landed on the islandand saw no one, Henderson's population had ceased to exist. Pitcairn's ownpopulation had disappeared at least by 1790 (the year when the Bounty mu-tineers arrived to find the island uninhabited), and probably disappearedmuch earlier.Why did Henderson's contact with the outside world come to a halt?That outcome stemmed from disastrous environmental changes on Man-gareva and Pitcairn. All over Polynesia, human settlement on islands thathad developed for millions of years in the absence of humans led to habitatdamage and mass extinctions of plants and animals. Mangareva was espe-cially susceptible to deforestation for most of the reasons that I identifiedfor Easter Island in the preceding chapter: high latitude, low ash and dustfallout, and so on. Habitat damage was extreme in Mangareva's hilly inte-rior, most of which the islanders proceeded to deforest in order to planttheir gardens. As a result, rain carried topsoil down the steep slopes, and theforest became replaced by a savannah of ferns, which were among the fewplants able to grow on the now-denuded ground. That soil erosion in thehills removed much of the area formerly available on Mangareva for gar-dening and tree crops. Deforestation indirectly reduced yields from fishingas well, because no trees large enough to build canoes remained: when Eu-ropeans "discovered" Mangareva in 1797, the islanders had no canoes, onlyrafts.With too many people and too little food, Mangareva society slid into anightmare of civil war and chronic hunger, whose consequences are recalledin detail by modern islanders. For protein, people turned to cannibalism, inthe form not only of eating freshly dead people but also of digging up andeating buried corpses. Chronic fighting broke out over the precious remain-ing cultivable land; the winning side redistributed the land of the losers.Instead of an orderly political system based on hereditary chiefs, non-hereditary warriors took over. The thought of Lilliputian military dictator-ships on eastern and western Mangareva, battling for control of an islandonly five miles long, could seem funny if it were not so tragic. All that politi-cal chaos alone would have made it difficult to muster the manpower and supplies necessary for oceangoing canoe travel, and to go off for a monthand leave one's garden undefended, even if trees for canoes themselves hadnot become unavailable. With the collapse of Mangareva at its hub, thewhole East Polynesia trade network that had joined Mangareva to the Marquesas, Societies, Tuamotus, Pitcairn, and Henderson disintegrated, as docu-I mented by Weisler's sourcing studies of basalt adzes.I While much less is known about environmental changes on Pitcairn,I limited archaeological excavations there by Weisler indicate massive defor-;estation and soil erosion on that island as well. Henderson itself also sufferedenvironmental damage that reduced its human carrying capacity. Five out of itsnine species of land birds (including all three large pigeons), and i coloniesof about six of its species of breeding seabirds, were exterminated. ; Thoseextinctions probably resulted from a combination of hunting for food, habitatdestruction due to parts of the island being burned for gar-i dens, anddepredations of rats that arrived as stowaways in Polynesian ; canoes.Today, those rats continue to prey on chicks and adults of the remainingspecies of seabirds, which are unable to defend themselves i because theyevolved in the absence of rats. Archaeological evidence for gardening appears onHenderson only after those bird disappearances, suggesting that people werebeing forced into reliance on gardens by the dwindling of their original foodsources. The disappearance of edible horn shells and decline in turban shells inlater layers of archaeological sites on Henderson's northeast coast also suggestthe possibility of overexploitation of shellfish.Thus, environmental damage, leading to social and political chaos andto loss of timber for canoes, ended Southeast Polynesia's interisland trade.That end of trade would have exacerbated problems for Mangarevans, nowcut off from Pitcairn, Marquesas, and Societies sources of high-qualityi stone for making tools. For the inhabitants of Pitcairn and Henderson, theresults were even worse: eventually, no one was left alive on those islands.Those disappearances of Pitcairn's and Henderson's populations must'; have resulted somehow from the severing of the Mangarevan umbilicalcord. Life on Henderson, always difficult, would have become more so withthe loss of all imported volcanic stone. Did everyone die simultaneously in amass calamity, or did the populations gradually dwindle down to a singlesurvivor, who lived on alone with his or her memories for many years? Thatactually happened to the Indian population of San Nicolas Island off LosAngeles, reduced finally to one woman who survived in complete isolationfor 18 years. Did the last Henderson Islanders spend much time on thebeaches, for generation after generation, staring out to sea in the hopes ofsighting the canoes that had stopped coming, until even the memory ofwhat a canoe looked like grew dim?While the details of how human life flickered out on Pitcairn and Hen-derson remain unknown, I can't tear myself free of the mysterious drama.In my head, I run through alternative endings of the movie, guiding myspeculation by what I know actually did happen to some other isolated soci-eties. When people are trapped together with no possibility of emigration,enemies can no longer resolve tensions merely by moving apart. Those ten-sions may have exploded in mass murder, which later nearly did destroy thecolony of Bounty mutineers on Pitcairn itself. Murder could also have beendriven by food shortage and cannibalism, as happened to the Mangarevans,Easter Islanders, and—closer to home for Americans—the Donner Party inCalifornia. Perhaps people grown desperate turned to mass suicide, whichwas recently the choice of 39 members of the Heaven's Gate cult near SanDiego, California. Desperation might instead have led to insanity, the fateof some members of the BelgianAntarctic Expedition, whose ship wastrapped by ice for over a year in 1898-1899. Still another catastrophic end-ing could have been starvation, the fate of Japan's garrison stranded onWake Island during World War II, and perhaps exacerbated by a drought,typhoon, tsunami, or other environmental disaster.Then my mind turns to gentler possible endings of the movie. After afew generations of isolation on Pitcairn or Henderson, everyone in theirmicrosociety of a hundred or a few dozen people would have been everyoneelse's cousin, and it would have become impossible to contract a marriagenot in violation of incest taboos. Hence people may just have grown old to-gether and stopped having children, as happened to California's last surviv-ing Yahi Indians, the famous Ishi and his three companions. If the smallpopulation did ignore incest taboos, the resulting inbreeding may havecaused congenital physical anomalies to proliferate, as exemplified by deaf-ness on Martha's Vineyard Island off Massachusetts or on the remote At-lantic island of Tristan da Cunha.We may never know which way the movies of Pitcairn and Hendersonactually ended. Regardless of the final details, though, the main outline ofthe story is clear. The populations of Mangareva, Pitcairn, and Hendersonall inflicted heavy damage on their environments and destroyed many ofthe resources necessary for their own lives. Mangareva Islanders were nu-merous enough to survive, albeit under chronically terrifying conditionsand with a drastically reduced standard of living. But from the very begin-ning, even before the accumulation of environmental damage, the inhabi-tants of Pitcairn and Henderson had remained dependent on imports ofagricultural products, technology, stone, oyster shell, and people from theirmother population on Mangareva. With Mangareva's decline and its in-ability to sustain exports, not even the most heroic efforts to adapt couldsave the last people alive on Pitcairn and Henderson. Lest those islands stillseem to you too remote in space and time to be relevant to our modern so-cieties, just think about the risks (as well as the benefits) of our increasingglobalization and increasing worldwide economic interdependence. Manyeconomically important but ecologically fragile areas (think of oil) alreadyaffect the rest of us, just as Mangareva affected Pitcairn and Henderson.C H A P T E R 4The Ancient Ones: TheAnasazi and Their NeighborsDesert farmers Tree rings Agricultural strategies Chaco's problems and packrats Regional integration Chaco's decline and end Chaco's messagef the sites of societal collapses considered in this book, the mostremote are Pitcairn and Henderson Islands discussed in the lastchapter. At the opposite extreme, the ones closest to home forAmericans are the Anasazi sites of Chaco Culture National Historical Park(Plates 9, 10) and Mesa Verde National Park, lying in the U.S. Southwest onNew Mexico state highway 57 and near U.S. highway 666, respectively, lessthan 600 miles from my home in Los Angeles. Like the Maya cities that willbe the subject of the next chapter, they and other ancient Native Americanruins are popular tourist attractions that thousands of modern First Worldcitizens visit each year. One of those former southwestern cultures, Mim-bres, is also a favorite of art collectors because of its beautiful pottery deco-ratedwith geometrical patterns and realistic figures: a unique tradition createdby a society numbering barely 4,000 people, and sustained at its peak forjust a few generations before abruptly disappearing.I concede that U.S. southwestern societies operated on a much smallerscale than did Maya cities, with populations of thousands rather than mil-ions. As a result, Maya cities are far more extensive in area, have more lavishmonuments and art, were products of more steeply stratified societiesleaded by kings, and possessed writing. But the Anasazi did manage to con-struct in stone the largest and tallest buildings erected in North Americauntil the Chicago steel girder skyscrapers of the 1880s. Even though theAnasazi lacked a writing system such as the one that allows us to date Mayainscriptions to the exact day, we shall see that many U.S. southwesternstructures can still be dated to within a year, thereby enablingarchaeologists to understand the societies' history with much finer timeresolution than is possible for Easter, Pitcairn, and Henderson Islands.OIn the U.S. Southwest we are dealing with not just a single cultureand collapse, but with a whole series of them (map, p. 142). Southwesterncultures that underwent regional collapses, drastic reorganizations, or aban-donments at different locations and different times include Mimbresaround A.D. 1130; Chaco Canyon, North Black Mesa, and the Virgin Anasaziin the middle or late 12th century; around 1300, Mesa Verde and theKayenta Anasazi; Mogollon around 1400; and possibly as late as the 15thcentury, Hohokam, well known for its elaborate system of irrigation agri-culture. While all of those sharp transitions occurred before Columbus's ar-rival in the New World in 1492, the Anasazi did not vanish as people: othersouthwestern Native American societies incorporating some of their de-scendants persist to this day, such as the Hopi and Zuni pueblos. What ac-counts for all those declines or abrupt changes in so many neighboringsocieties?Favorite single-factor explanations invoke environmental damage,drought, or warfare and cannibalism. Actually, the field of U.S. southwest-ern prehistory is a graveyard for single-factor explanations. Multiple factorshave operated, but they all go back to the fundamental problem that theU.S. Southwest is a fragile and marginal environment for agriculture—as isalso much of the world today. It has low and unpredictable rainfall, quicklyexhausted soils, and very low rates of forest regrowth. Environmental prob-lems, especially major droughts and episodes of streambed erosion, tend torecur at intervals much longer than a human lifetime or oral memory span.Given those severe difficulties, it's impressive that Native Americans in theSouthwest developed such complex farming societies as they did. Testimonyto their success is that most of this area today supports a much sparserpopulation growing their own food than it did in Anasazi times. It was amoving and unforgettable experience for me, while I was driving throughareas of desert dotted with the remains of former Anasazi stone houses,dams, and irrigation systems, to see a now virtually empty landscape withjust the occasional occupied house. The Anasazi collapse and other south-western collapses offer us not only a gripping story but also an instructiveone for the purposes of this book, illustrating well our themes of humanenvironmental impact and climate change intersecting, environmental andpopulation problems spilling over into warfare, the strengths but also thedangers of complex non-self-sufficient societies dependent on imports andexports, and societies collapsing swiftly after attaining peak populationnumbers and power.Our understanding of southwestern prehistory is detailed because of twoadvantages that archaeologists in this area enjoy. One is the packrat middenmethod that I'll discuss below, which provides us with a virtual time capsuleof the plants growing within a few dozen yards of a midden within a few de-cades of a calculated date. That advantage has allowed paleobotanists toreconstruct changes in local vegetation. The other advantage allows archae-ologists to date building sites to the nearest year by the tree rings of the site'swood construction beams, instead of having to rely on the radiocarbonmethod used by archaeologists elsewhere, with its inevitable errors of 50 to100 years.The tree ring method depends on the fact that rainfall and temperaturevary seasonally in the Southwest, so that tree growth ratesalso vary season-ally, as true at other sites in the temperate zones as well. Hence temperatezone trees lay down new wood in annual growth rings, unlike tropical rain-forest trees whose growth is more nearly continuous. But the Southwest isbetter for tree ring studies than most other temperate zone sites, becausethe dry climate results in excellent preservation of wooden beams fromtrees felled over a thousand years ago.Here's how tree ring dating, known to scientists as dendrochronology(from the Greek roots dendron = tree, and chronos = time), works. If you cutdown a tree today, it's straightforward to count the rings inwards, startingfrom the tree's outside (corresponding to this year's growth ring), andthereby to state that the 177th ring from the outermost one towards thecenter was laid down in the year 2005 minus 177, or 1828. But it's lessstraightforward to attach a date to a particular ring in an ancient Anasaziwooden beam, because at first you don't know in what year the beam wascut. However, the widths of tree growth rings vary from year to year, de-pending on rain or drought conditions in each year. Hence the sequence ofrings in a tree cross-section is like a message in the Morse code formerlyused for sending telegraph messages; dot-dot-dash-dot-dash in the Morsecode, wide-wide-narrow-wide-narrow in a tree ring sequence. Actually, thering sequence is even more diagnostic and richer in information than theMorse code, because trees actually contain rings spanning many differentwidths, rather than the Morse code's choice between only a dot or a dash.Tree ring specialists (known as dendrochronologists) proceed by notingthe sequence of wider and narrower rings in a tree cut down in a known re-cent year, and also noting the sequence in beams from trees cut down atvarious unknown times in the past. They then match up and align ringsequences with the same diagnostic wide/narrow patterns from differentbeams. For instance, suppose that this year (2005) you cut down a tree thatproves to be 400 years old (400 rings), and that has an especially distinctivesequence of five wide rings, two narrow rings, and six wide rings for the 13years from 1643 back to 1631. If you find that same distinctive sequencestarting seven years from the outermost ring in an old beam of unknown fellingdate with 332 rings, then you can conclude that the old beam came from a treecut down in 1650 (seven years after 1643), and that the tree began to grow in theyear 1318 (332 years before 1650). You then go on to align that beam, from thetree living between 1318 and 1650, with even older beams, and you similarly tryto match up tree ring patterns and find a beam whose pattern shows that it comesfrom a tree that was cut down after 1318 but began growing before 1318,thereby extending your tree ring record farther back into the past. In that way,dendrochronologists have constructed tree ring records extending back forthousands of years in some parts of the world. Each such record is valid for ageographic area whose extent depends on local weather patterns, becauseweather and hence tree growth patterns vary with location. For instance, thebasic tree ring chronology of the American Southwest applies (with somevariation) to the area from northern Mexico to Wyoming.A bonus of dendrochronology is that the width and substructure of each ringreflect the amount of rain and the season at which the rain fell during thatparticular year. Thus, tree ring studies also allow one to reconstruct past climate;e.g., a series of wide rings means a wet period, and a series of narrow ringsmeans a drought. Tree rings thereby provide southwestern archaeologists withuniquely exact dating and uniquely detailed year-to-year environmentalinformation.The first humans to reach the Americas, living as hunter-gatherers, arrived in theU.S. Southwest by 11,000 B.C. but possibly earlier, as part of the colonization ofthe New World from Asia by peoples ancestral to modern Native Americans.Agriculture did not develop indigenously in the U.S. Southwest, because of apaucity of domesticable wild plant and animal species. Instead, it arrived fromMexico, where corn, squash, beans, and many other crops were domesticated—corn arriving by 2000 B.C., squash around 800 B.C., beans somewhat later, andcotton not until A.D. 400. People also kept domestic turkeys, about which thereis some debate whether they were first domesticated in Mexico and spread to theSouthwest, or vice versa, or whether they were domesticated independently inboth areas. Originally,southwestern Native Americans just incorporated some agriculture as partof their hunter-gatherer lifestyle, as did the modern Apache in the 18th and19th centuries: the Apache settled down to plant and harvest crops duringthe growing season, then moved around as hunter-gatherers during the restof the year. By A.D. 1, some southwestern Native Americans had alreadytaken up residence in villages and become primarily dependent on agricul-ture with ditch irrigation. Thereafter, their populations exploded in num-bers and spread over the landscape until the retrenchments beginningaround A.D. 1117.At least three alternative types of agriculture emerged, all involving dif-ferent solutions to the Southwest's fundamental problem: how to obtainenough water to grow crops in an environment most of which has rainfallso low and unpredictable that little or no farming is practiced there today.One of the three solutions consisted of so-called dryland agriculture, whichmeant relying on rainfall at the higher elevations where there really wasenough rain to promote growth of crops in the fields on which the rain fell.A second solution did not depend on rain falling directly on the field, butinstead was adopted in areas where the water table in the ground reachedclose enough to the surface that plant roots could extend down into the wa-ter table. That method was employed in canyon bottoms with intermittentor permanent streams and a shallow alluvial groundwater table, such as inChaco Canyon. The third solution, practiced especially by the Hohokamand also at Chaco Canyon, consisted of collecting water runoff in ditches orcanals to irrigate fields.While the methods used in the Southwest to obtain enough water togrow crops were variants on those three types, people experimented in dif-ferent locations with alternative strategies for applying those methods.The experiments lasted for almost a thousand years, and many of themsucceeded for centuries, but eventually all except one succumbed to envi-ronmental problems caused by human impact or climate change. Each al-ternative involved different risks.One strategy was to live at higher elevations where rainfall was higher, asdid the Mogollon, the people at Mesa Verde, and the people of the earlyagricultural phase known as the Pueblo I phase. But that carried the riskthat it is cooler at high than at low elevations, and in an especially cool yearit might be too cold to grow crops at all. An opposite extreme was to farm atthe warmer low elevations, but there the rainfall is insufficient for drylandagriculture. The Hohokam got around that problem by constructing themost extensive irrigation system in the Americas outside Peru, with hun-dreds of miles of secondary canals branching off a main canal 12 mileslong, 16 feet deep, and 80 feet wide. But irrigation entailed the risk that hu-man cutting of ditches and canals could lead to sudden heavy water runofffrom rainstorms digging further down into the ditches and canals and in-cising deep channels called arroyos, in which the water level would drop be-low the field level, making irrigation impossible for people without pumps.Also, irrigation poses the danger that especially heavy rains or floods couldwash away the dams and channels, as may indeed eventually have happenedto the Hohokam.Another, more conservative, strategy was to plant crops onlyin areaswith reliable springs and groundwater tables. That was the solution initiallyadopted by the Mimbres, and by people in the farming phase known asPueblo II at Chaco Canyon. However, it then became dangerously temptingto expand agriculture, in wet decades with favorable growing conditions,into marginal areas with less reliable springs or groundwater. The popula-tion multiplying in those marginal areas might then find itself unable togrow crops and starving when the unpredictable climate turned dry again.That fate actually befell the Mimbres, who started by safely farming thefloodplain and then began to farm adjacent land above the floodplain astheir population came to saturate the fioodplain's capacity to support it.They got away with their gamble during a wet climate phase, when theywere able to obtain half of their food requirements outside the floodplain.However, when drought conditions returned, that gamble left them with apopulation double what the floodplain could support, and Mimbres societycollapsed suddenly under the stress.Still another solution was to occupy an area for only a few decades, untilthe area's soil and game became exhausted, then to move on to anotherarea. That method worked when people were living at low population den-sities, so that there were lots of unoccupied areas to which to move, and sothat each occupied area could be left unoccupied again for sufficiently longafter occupation that its vegetation and soil nutrients had time to recover.Most southwestern archaeological sites were indeed inhabited for only a fewdecades, even though our attention today is drawn to a few big sites thatwere inhabited continuously for several centuries, such as Pueblo Bonito inChaco Canyon. However, the method of shifting sites after a short occupa-tion became impossible at high population densities, when people filled upthe whole landscape and there was nowhere left empty to move to.One more strategy was to plant crops at many sites even though rainfallis locally unpredictable, and then to harvest crops at whichever sites did getenough rain to produce a good harvest, and to redistribute some of thatharvest to the people still living at all the sites that didn't happen to receiveenough rain that year. That was one of the solutions eventually adopted atChaco Canyon. But it involved the risk that redistribution required a com-plex political and social system to integrate activities between different sites,and that lots of people then ended up starving when that complex systemcollapsed.The remaining strategy was to plant crops and live near permanent ordependable sources of water, but on landscape benches above the mainfloodways, so as to avoid the risk of a heavy flood washing out fields and vil-lages; and to practice a diverse economy, exploiting ecologically diversezones, so that each settlement would be self-sufficient. That solution,adopted by people whose descendants live today in the Southwest's Hopiand Zuni Pueblos, has succeeded for more than a thousand years. Somemodern Hopis and Zunis, looking at the extravagance of American societyaround them, shake their heads and say, "We were here long before youcame, and we expect still to be here long after you too are gone."All of these alternative solutions face a similar overarching risk: that aseries of good years, with adequate rainfall or with sufficiently shallowgroundwater tables, may result in population growth, resulting in turn insociety becoming increasingly complex and interdependent and no longerlocally self-sufficient. Such a society then cannot cope with, and rebuild it-self after, a series of bad years that a less populous, less interdependent,more self-sufficient society had previously been able to cope with. As weshall see, precisely that dilemma ended Anasazi settlement of Long HouseValley, and perhaps other areas as well.The most intensively studied abandonment was of the most spectacular andlargest set of sites, the Anasazi sites in Chaco Canyon of northwestern NewMexico. Chaco Anasazi society flourished from about A.D. 600 for morethan five centuries, until it disappeared some time between 1150 and 1200.It was a complexly organized, geographically extensive, regionally inte-grated society that erected the largest buildings in pre-Columbian NorthAmerica. Even more than the barren treeless landscape of Easter Island, thebarren treeless landscape of Chaco Canyon today, with its deep-cut arroyosand sparse low vegetation of salt-tolerant bushes, astonishes us, because thecanyon is now completely uninhabited except for a few National Park Ser-vice rangers' houses. Why would anyone have built an advanced city in thatwasteland, and why, having gone to all that work of building it, did theythen abandon it?When Native American farmers moved into the Chaco Canyon areaaround A.D. 600, they initially lived in underground pit houses, as did othercontemporary Native Americans in the Southwest. Around A.D. 700 theChaco Anasazi, out of contact with Native American societies buildingstructures of stone a thousand miles to the south in Mexico, independentlyinvented techniques of stone construction and eventually adopted rubblecores with veneers of cut stone facing (Plate 11). Initially, those structureswere only one story high, but around A.D. 920 what eventually became thelargest Chacoan site of Pueblo Bonito went up to two stories, then over thenext two centuries rose to five or six stories with 600 rooms whose roof sup-ports were logs up to 16 feet long and weighing up to 700 pounds.Why, out of all the Anasazi sites, was it at Chaco Canyon that construc-tion techniques and political and societal complexity reached their apogee?Likely reasons are some environmental advantages of Chaco Canyon, whichinitially represented a favorable environmental oasis within northwesternNew Mexico. The narrow canyon caught rain runoff from many side-channels and a large upland area, which resulted in high alluvial ground-water levels permitting farming independent of local rainfall in some areas,and also high rates of soil renewal from the runoff. The large habitable areain the canyon and within 50 miles of it could support a relatively highpopulation for such a dry environment. The Chaco region has a high diver-sity of useful wild plant and animal species, and a relatively low elevationthat provides a long growing season for crops. At first, nearby pinyon andjuniper woodlands provided the construction logs and firewood. The earli-est roof beams identified by their tree rings, and still well preserved in theSouthwest's dry climate, are of locally available pinyon pines, and firewoodremains in early hearths are of locally available pinyon and juniper. Anasazidiets depended heavily on growing corn, plus some squash and beans, butearly archaeological levels also show much consumption of wild plants suchas pinyon nuts (75% protein), and much hunting of deer.All those natural advantages of Chaco Canyon were balanced by twomajor disadvantages resulting from the Southwest's environmental fragility.One involved problems of water management. Initially, rain runoff wouldhave been as a broad sheet over the flat canyon bottom, permitting flood-plain agriculture watered both by the runoff and by the high alluvialgroundwater table. When the Anasazi began diverting water into channelsfor irrigation, the concentration of water runoff in the channels and theclearing of vegetation for agriculture, combined with natural processes, re-sulted around A.D. 900 in the cutting of deep arroyos in which the waterlevel was below field levels, thereby making irrigation agriculture and alsoagriculture based on groundwater impossible until the arroyos filled upagain. Such arroyo-cutting can develop surprisingly suddenly. For example,at the Arizona city of Tucson in the late 1880s, American settlers excavated aso-called intercept ditch to interceptthe shallow groundwater table and di-vert its water downstream onto the floodplain. Unfortunately, floods fromheavy rains in the summer of 1890 cut into the head of that ditch, startingan arroyo that within a mere three days extended itself for a distance ofsix miles upstream, leaving an incised and agriculturally useless flood-plainnear Tucson. Early Southwest Native American societies probably at-tempted similar intercept ditches, with similar results. The Chaco Anasazidealt with that problem of arroyos in the canyon in several ways: by build-ing dams inside side-canyons above the elevation of the main canyon tostore rainwater; by laying out field systems that that rainwater could irri-gate; by storing rainwater coming down over the tops of the cliffs rimmingthe canyon's north wall between each pair of side-canyons; and by buildinga rock dam across the main canyon.The other major environmental problem besides water management in-volved deforestation, as revealed by the method of packrat midden analysis.For those of you who (like me until some years ago) have never seen pack-rats, don't know what their middens are, and can't possibly imagine theirrelevance to Anasazi prehistory, here is a quick crash course in middenanalysis. In 1849, hungry gold miners crossing the Nevada desert noticedsome glistening balls of a candy-like substance on a cliff, licked or ate theballs, and discovered them to be sweet-tasting, but then they developednausea. Eventually it was realized that the balls were hardened depositsmade by small rodents, called packrats, that protect themselves by buildingnests of sticks, plant fragments, and mammal dung gathered in the vicinity,plus food remains, discarded bones, and their own feces. Not being toilet-trained, the rats urinate in their nests, and sugar and other substances crys-tallize from their urine as it dries out, cementing the midden to a brick-likeconsistency. In effect, the hungry gold miners were eating dried rat urinelaced with rat feces and rat garbage.Naturally, to save themselves work and to minimize their risk of beinggrabbed by a predator while out of the nest, packrats gather vegetationwithin just a few dozen yards of the nest. After a few decades the rats'progeny abandon their midden and move on to build a new nest, while thecrystallized urine prevents the material in the old midden from decaying.By identifying the remains of the dozens of urine-encrusted plant speciesin a midden, paleobotanists can reconstruct a snapshot of the vegetationgrowing near the midden at the time that the rats were accumulating it,while zoologists can reconstruct something of the fauna from the insect andvertebrate remains. In effect, a packrat midden is a paleontologist's dream: atime capsule preserving a sample of the local vegetation, gathered within afew dozen yards of the spot within a period of a few decades, at a date fixedby radiocarbon-dating the midden.In 1975 paleoecologist Julio Betancourt happened to visit Chaco Can-yon while driving through New Mexico as a tourist. Looking down on thetreeless landscape around Pueblo Bonito, he thought to himself, "This placelooks like beat-up Mongolian steppe; where did those people get their tim-ber and firewood?" Archaeologists studying the ruins had been askingthemselves the same question. In a moment of inspiration three years later,when a friend asked him for completely unrelated reasons to write a grantproposal to study packrat middens, Julio recalled his first impression ofPueblo Bonito. A quick phone call to midden expert Tom Van Devender es-tablished that Tom had already collected a few middens at the National ParkService campground near Pueblo Bonito. Almost all of them had proved tocontain needles of pinyon pines, which don't grow anywhere within milestoday but which had nevertheless somehow furnished the roof beams forearly phases of Pueblo Bonito's construction, as well as furnishing much ofthe charcoal found in hearths and trash middens. Julio and Tom realizedthat those must be old middens from a time when pines did grow nearby,but they had no idea how old: they thought perhaps just a century or so.Hence they submitted samples of those middens for radiocarbon dating.When the dates came back from the radiocarbon laboratory, Julio and Tomwere astonished to learn that many of the middens were over a thousandyears old.That serendipitous observation triggered an explosion of packrat mid-den studies. Today we know that middens decay extremely slowly in theSouthwest's dry climate. If protected from the elements under an overhangor inside a cave, middens can last 40,000 years, far longer than anyonewould have dared to guess. As Julio showed me my first packrat middennear the Chaco Anasazi site of Kin Kletso, I stood in awe at the thought thatthat apparently fresh-looking nest might have been built at a time whenmammoths, giant ground sloths, American lions, and other extinct Ice Agemammals were still living in the territory of the modern U.S.In the Chaco Canyon area Julio went on to collect and radiocarbon-date50 middens, whose dates turned out to encompass the entire period of therise and fall of Anasazi civilization, from A.D. 600 to 1200. In this way Juliowas able to reconstruct vegetational changes in Chaco Canyon throughoutthe history of Anasazi occupation. Those midden studies identified defor-estation as the other one (besides water management) of the two major envi-ronmental problems caused by the growing population that had developedin Chaco Canyon by around A.D. 1000. Middens before that date still incor-porated pinyon pine and juniper needles, like the first midden that Julio hadanalyzed, and like the midden that he showed me. Hence Chaco Anasazi set-tlements were initially constructed in a pinyon/juniper woodland unlike thepresent treeless landscape but convenient for obtaining firewood and con-struction timber nearby. However, middens dated after A.D. 1000 lackedpinyon and juniper, showing that the woodland had then become com-pletely destroyed and the site had achieved its present treeless appearance.The reason why Chaco Canyon became deforested so quickly is the sameas the reason that I discussed in Chapter 2 to explain why Easter Island andother dry Pacific islands settled by people were more likely to end up defor-ested than were wet islands: in a dry climate, the rate of tree regrowth onlogged land may be too slow to keep up with the rate of logging.The loss of the woodland not only eliminated pinyon nuts as a local foodsupply but also forced Chaco residents to find a different timber source fortheir construction needs, as shown by the complete disappearance ofpinyon beams from Chaco architecture. Chacoans coped by going far afieldto forests of ponderosa pine, spruce, and fir trees, growing in mountains upto 50 miles away at elevations several thousand feet higher than ChacoCanyon. With no draft animals available, about 200,000 logs weighing eachup to 700 pounds were carried down the mountains and over that distanceto Chaco Canyon by human muscle power alone.A recent study by Julio's student Nathan English, working in collabora-tion with Julio, Jeff Dean, and Jay Quade, identified more exactly where thebig spruce and fir logs came from. There are three potential sources of themin the Chaco area, growing at high elevations on three mountain rangesnearly equidistant from the canyon: the Chuska, San Mateo, and San PedroMountains. From which of those mountains did the Chaco Anasazi actuallyget their conifers? Trees from the three mountain ranges belong to the samespecies and look identical to each other. As a diagnostic signature, Nathanused isotopes of strontium, an element chemically very similar to calciumand hence incorporated along with calcium into plants and animals. Stron-tium exists as alternative forms (isotopes) differing slightly in atomicweight, of which strontium-87 and strontium-86are commonest in na-ture. But the strontium-87/strontium 86 ratio varies with rock age androck rubidium content, because strontium is produced by radioactive de-cay of a rubidium isotope. It turned out that living conifers from the threemountain ranges proved to be clearly separated by their strontium-87/strontium-86 ratios, with no overlap at all. From six Chaco ruins, Nathansampled 52 conifer logs selected on the basis of their tree rings to have beenfelled at dates ranging from A.D. 974 to 1104. The result he obtained wasthat two-thirds of the logs could be traced by their strontium ratios to theChuska Mountains, one-third to the San Mateo Mountains, and none at allto the San Pedro Mountains. In some cases a given Chaco building incorpo-rated logs from both mountain ranges in the same year, or used logs fromone mountain in one year and from the other mountain in another year,while the same mountain furnished logs to several different buildings in thesame year. Thus, we have here unequivocal evidence of a well-organized,long-distance supply network for the Anasazi capital of Chaco Canyon.Despite the development of these two environmental problems that re-duced crop production and virtually eliminated timber supplies withinChaco Canyon itself, or because of the solutions that the Anasazi found tothese problems, the canyon's population continued to increase, particularlyduring a big spurt of construction that began in A.D. 1029. Such spurts wenton especially during wet decades, when more rain meant more food, morepeople, and more need for buildings. A dense population is attested notonly by the famous Great Houses (such as Pueblo Bonito) spaced about amile apart on the north side of Chaco Canyon, but also by holes drilled intothe northern cliff face to support roof beams, indicating a continuous lineof residences at the base of the cliffs between the Great Houses, and by theremains of hundreds of small settlements on the south side of the canyon.The size of the canyon's total population is unknown and much debated.Many archaeologists think that it was less than 5,000, and that those enor-mous buildings had few permanent occupants except priests and were justvisited seasonally by peasants at the time of rituals. Other archaeologistsnote that Pueblo Bonito, which is just one of the large houses at ChacoCanyon, by itself was a building of 600 rooms, and that all those post holessuggest dwellings for much of the length of the canyon, thus implying apopulation much greater than 5,000. Such debates about estimated popula-tion sizes arise frequently in archaeology, as discussed for Easter Island andthe Maya in other chapters of this book.Whatever the number, this dense population could no longer support it-self but was subsidized by outlying satellite settlements constructed in simi-lar architectural styles and joined to Chaco Canyon by a radiating regionalnetwork of hundreds of miles of roads that are still visible today. Those out-liers had dams to catch rain, which fell unpredictably and very patchily: athunderstorm might produce abundant rain in one desert wash and no rainin another wash just a mile away. The dams meant that when a particularwash was fortunate enough to receive a rainstorm, much of the rainwaterbecame stored behind the dam, and people living there could quickly plantcrops, irrigate, and grow a huge surplus of food at that wash in that year.The surplus could then feed people living at all the other outliers that didn'thappen to receive rain then.Chaco Canyon became a black hole into which goods were imported butfrom which nothing tangible was exported. Into Chaco Canyon came: thosetens of thousands of big trees for construction; pottery (all late-period pot-tery in Chaco Canyon was imported, probably because exhaustion of localfirewood supplies precluded firing pots within the canyon itself); stone ofgood quality for making stone tools; turquoise for making ornaments, fromother areas of New Mexico; and macaws, shell jewelry, and copper bellsfrom the Hohokam and from Mexico, as luxury goods. Even food had to beimported, as shown by a recent study tracing the origins of corncobs exca-vated from Pueblo Bonito by means of the same strontium isotope methodused by Nathan English to trace the origins of Pueblo Bonito's woodenbeams. It turns out that, already in the 9th century, corn was being im-ported from the Chuska Mountains 50 miles to the west (also one of thetwo sources of roof beams), while a corncob from the last years of PuebloBonito in the 12th century came from the San Juan River system 60 miles tothe north.Chaco society turned into a mini-empire, divided between a well-fedelite living in luxury and a less well-fed peasantry doing the work and rais-ing the food. The road system and the regional extent of standardized archi-tecture testify to the large size of the area over which the economy andculture of Chaco and its outliers were regionally integrated. Styles of build-ings indicate a three-step pecking order: the largest buildings, so-calledGreat Houses, in Chaco Canyon itself (residences of the governing chiefs?);outlier Great Houses beyond the canyon ("provincial capitals" of juniorchiefs?); and small homesteads of just a few rooms (peasants' houses?).Compared to smaller buildings, the Great Houses were distinguished byfiner construction with veneer masonry, large structures called Great Kivasused for religious rituals (similar to ones still used today in modern Pueb-los), and a higher ratio of storage space to total space. Great Houses far ex-ceeded homesteads in their contents of imported luxury goods, such as theturquoise, macaws, shell jewelry, and copper bells mentioned above, plusimported Mimbres and Hohokam pottery. The highest concentration ofluxury items located to date comes from Pueblo Bonito's room number 33,which held burials of 14 individuals accompanied by 56,000 pieces ofturquoise and thousands of shell decorations, including one necklace of2,000 turquoise beads and a basket covered with a turquoise mosaic andfilled with turquoise and shell beads. As for evidence that the chiefs ate bet-ter than did the peasants, garbage excavated near Great Houses contained ahigher proportion of deer and antelope bones than did garbage from home-steads, with the result that human burials indicate taller, better-nourished,less anemic people and lower infant mortality at Great Houses.Why would outlying settlements have supported the Chaco center, duti-fully delivering timber, pottery, stone, turquoise, and food without receivinganything material in return? The answer is probably the same as the reasonwhy outlying areas of Italy and Britain today support our cities such asRome and London, which also produce no timber or food but serve as po-litical and religious centers. Like the modern Italians and British, Chacoanswere now irreversibly committed to living in a complex, interdependentsociety. They could no longer revert to their original condition of self-supporting mobile little groups, because the trees in the canyon were gone,the arroyos were cut below field levels, and the growing population hadfilled up the region and left no unoccupied suitable areas to which to move.When the pinyon and juniper trees were cut down, the nutrients in the litterunderneath the trees were flushed out. Today, more than 800 years later,there is still no pinyon/juniper woodland growing anywhere near the pack-rat middens containing twigs of the woodland that had grown there beforeA.D. 1000. Food remains in rubbish at archaeological sites attest to thegrowing problems of the canyon's inhabitants in nourishing themselves:deer declined in their diets, to be replaced by smaller game, especially rab-bits and mice. Remains of complete headless mice in human coprolites(preserved dry feces) suggest that people were catching mice in the fields,beheading them, and popping them in whole.The last identified construction at Pueblo Bonito, dating from the decadeafter 1110, was from a wall of rooms enclosing the south side of the plaza,which had formerly been open to the outside. That suggests strife: peoplewere evidently now visiting Pueblo Bonito not just to participate in its reli-gious ceremonies and to receive orders, but also to make trouble. The lasttree-ring-dated roof beam at Pueblo Bonito and at the nearby Great Houseof Chetro Ketl was cut in A.D. 1117, and the last beam anywhere in ChacoCanyon in A.D. 1170. Other Anasazi sites show more abundant evidence ofstrife, including signs of cannibalism, plus Kayenta Anasazi settlements atthe tops of steep cliffs far from fields and water and understandable only aseasily defended locations. At those southwestern sites that outlasted Chacoand survived until after A.D. 1250, warfare evidently became intense, as re-flected in a proliferation of defensive walls and moats and towers, clusteringof scattered small hamlets into larger hilltop fortresses, apparently deliber-ately burned villages containing unburied bodies, skulls with cut markscaused by scalping, and skeletons with arrowheads inside the body cavity.That explosion of environmental and population problems in the form ofcivil unrest and warfare is a frequent theme in this book, both for past so-cieties (the Easter Islanders, Mangarevans, Maya, and Tikopians) and formodern societies (Rwanda, Haiti, and others).The signs of warfare-related cannibalism among the Anasazi are aninteresting story in themselves. While everyone acknowledges that canni-balism may be practiced in emergencies by desperate people, such as theDonner Party trapped by snow at Donner Pass en route to California in thewinter of 1846-47, or by starving Russians during the siege of Leningradduring World War II, the existence of non-emergency cannibalism is con-troversial. In fact, it was reported in hundreds of non-European societies atthe times when they were first contacted by Europeans within recent cen-turies. The practice took two forms: eating either the bodies of enemieskilled in war, or else eating one's own relatives who had died of naturalcauses. New Guineans with whom I have worked over the past 40 years havematter-of-factly described their cannibalistic practices, have expressed dis-gust at our own Western burial customs of burying relatives without doingthem the honor of eating them, and one of my best New Guinean workersquit his job with me in 1965 in order to partake in the consumption of hisrecently deceased prospective son-in-law. There have also been manyarchaeological finds of ancient human bones in contexts suggestive ofcannibalism.Nevetheless, many or most European and American anthropologists,brought up to regard cannibalism with horror in their own societies, arealso horrified at the thought of it being practiced by peoples that they ad-mire and study, and so they deny its occurrence and consider claims of it asracist slander. They dismiss all the descriptions of cannibalism by non-European peoples themselves or by early European explorers as unreliablehearsay, and they would evidently be convinced only by a videotape takenby a government official or, most convincing of all, by an anthropologist.However, no such tape exists, for the obvious reason that the first Euro-peans to encounter people reported to be cannibals routinely expressedtheir disgust at the practice and threatened its practitioners with arrest.Such objections have created controversy around the many reports ofhuman remains, with evidence consistent with cannibalism, found at Ana-sazi sites. The strongest evidence comes from an Anasazi site at which ahouse and its contents had been smashed, and the scattered bones of sevenpeople were left inside the house, consistent with their having been killed ina war raid rather than properly buried. Some of the bones had been crackedin the same way that bones of animals consumed for food were cracked toextract the marrow. Other bones showed smooth ends, a hallmark of ani-mal bones boiled in pots, but not of ones not boiled in pots. Broken potsthemselves from that Anasazi site had residues of the human muscle proteinmyoglobin on the pots' inside, consistent with human flesh having beencooked in the pots. But skeptics might still object that boiling human meatin pots, and cracking open human bones, does not prove that other humansactually consumed the meat of the former owners of those bones (thoughwhy else would they go to all that trouble of boiling and cracking bones tobe left scattered on the floor?). The most direct sign of cannibalism at thesite is that dried human feces, found in the house's hearth and still well pre-served after nearly a thousand years in that dry climate, proved to containhuman muscle protein, which is absent from normal human feces, evenfrom the feces of people with injured and bleeding intestines. This makes itprobable that whoever attacked that site, killed the inhabitants, crackedopen their bones, boiled their flesh in pots, scattered the bones, and re-lieved himself or herself by depositing feces in that hearth had actually con-sumed the flesh of his or her victims.The final blow for Chacoans was a drought that tree rings show to havebegun around A.D. 1130. There had been similar droughts previously,around A.D. 1090 and 1040, but the difference this time was that ChacoCanyon now held more people, more dependent on outlying settlements,and with no land left unoccupied. A drought would have caused thegroundwater table to drop below the level where it could be tapped by plantroots and could support agriculture; a drought would also make rainfall-supported dryland agriculture and irrigation agriculture impossible. Adrought that lasted more than three years would have been fatal, becausemodern Puebloans can store corn for only two or three years, after which itis too rotten or infested to eat. Probably the outlying settlements that hadformerly supplied the Chaco political and religious centers with food lostfaith in the Chacoan priests whose prayers for rain remained unanswered,and they refused to make more food deliveries. A model for the end ofAnasazi settlement at Chaco Canyon, which Europeans did not observe, iswhat happened in the Pueblo Indian revolt of 1680 against the Spaniards,a revolt that Europeans did observe. As in Chaco Anasazi centers, theSpaniards had extracted food from local farmers by taxing them, and thosefood taxes were tolerated until a drought left the farmers themselves shortof food, provoking them to revolt.Some time between A.D. 1150 and 1200, Chaco Canyon was virtuallyabandoned and remained largely empty until Navajo sheepherders reoccu-pied it 600 years later. Because the Navajo did not know who had built thegreat ruins that they found there, they referred to those vanished formerinhabitants as the Anasazi, meaning "the Ancient Ones." What actuallyhappened to the thousands of Chacoan inhabitants? By analogy with his-torically witnessed abandonments of other pueblos during a drought inthe 1670s, probably many people starved to death, some people killed eachother, and the survivors fled to other settled areas in the Southwest. It musthave been a planned evacuation, because most rooms at Anasazi sites lackthe pottery and other useful objects that people would be expected to takewith them in a planned evacuation, in contrast to the pottery still in therooms of the above-mentioned site whose unfortunate occupants werekilled and eaten. The settlements to which Chaco survivors managed toflee include some pueblos in the area of the modern Zuni pueblos, whererooms built in a style similar to Chaco Canyon houses and containingChaco styles of pottery have been found at dates around the time of Chaco'sabandonment.Jeff Dean and his colleagues Rob Axtell, Josh Epstein, George Gumer-man, Steve McCarroll, Miles Parker, and AlanSwedlund have carried out anespecially detailed reconstruction of what happened to a group of about athousand Kayenta Anasazi in Long House Valley in northeastern Arizona.They calculated the valley's actual population at various times fromA.D. 800 to 1350, based on numbers of house sites containing pottery thatchanged in style with time, thereby permitting dating of the house sites.They also calculated the valley's annual corn harvests as a function of time,from annual tree rings that provide a measure of rainfall, and from soilstudies that provide information about the rise and fall of groundwater lev-els. It turned out that the rises and falls of the actual population after A.D.800 closely mirrored the rises and falls of calculated annual corn harvests,except that the Anasazi completely abandoned the valley by A.D. 1300, at atime when some reduced corn harvests sufficient to support one-third ofthe valley's peak population (400 out of the peak of 1,070 people) couldstill have been extracted.Why did those last 400 Kayenta Anasazi of Long House Valley not re-main when most of their relatives were leaving? Perhaps the valley inA.D. 1300 had deteriorated for human occupation in other ways besides itsreduced agricultural potential calculated in the authors' model. For in-stance, perhaps soil fertility had been exhausted, or else the former forestsmay have been felled, leaving no nearby timber for buildings and firewood,as we know to have been the case in Chaco Canyon. Alternatively, perhapsthe explanation was that complex human societies require a certain mini-mum population size to maintain institutions that its citizens consider to beessential. How many New Yorkers would choose to remain in New York Cityif two-thirds of their family and friends had just starved to death there orfled, if the subway trains and taxis were no longer running, and if officesand stores had closed?Along with those Chaco Canyon Anasazi and Long House Valley Anasaziwhose fates we have followed, I mentioned at the start of this chapter thatmany other southwestern societies—the Mimbres, Mesa Verdeans, Ho-hokam, Mogollon, and others—also underwent collapses, reorganizations,or abandonments at various times within the period A.D. 1100-1500. Itturns out that quite a few different environmental problems and cultural re-sponses contributed to these collapses and transitions, and that differentfactors operated in different areas. For example, deforestation was a prob-lem for the Anasazi, who required trees to supply the roof beams of theirhouses, but it wasn't as much of a problem for the Hohokam, who did notuse beams in their houses. Salinization resulting from irrigation agricultureiiurt the Hohokam, who had to irrigate their fields, but not the MesaVerdeans, who did not have to irrigate. Cold affected the Mogollon andMesa Verdeans, living at high altitudes and at temperatures somewhat mar-ginal for agriculture. Other southwestern peoples were done in by droppingwater tables (e.g., the Anasazi) or by soil nutrient exhaustion (possibly theMogollon). Arroyo cutting was a problem for the Chaco Anasazi, but notfor the Mesa Verdeans.Despite these varying proximate causes of abandonments, all were ulti-mately due to the same fundamental challenge: people living in fragile anddifficult environments, adopting solutions that were brilliantly successfuland understandable "in the short run," but that failed or else created fatalproblems in the long run, when people became confronted with externalenvironmental changes or human-caused environmental changes that soci-eties without written histories and without archaeologists could not haveanticipated. I put "in the short run" in quotation marks, because theAnasazi did survive in Chaco Canyon for about 600 years, considerablylonger than the duration of European occupation anywhere in the NewWorld since Columbus's arrival in A.D. 1492. During their existence, thosevarious southwestern Native Americans experimented with half-a-dozenalternative types of economies (pp. 140-143). It took many centuries todiscover that, among those economies, only the Pueblo economy wassustainable "in the long run," i.e., for at least a thousand years. That shouldmake us modern Americans hesitate to be too confident yet about the sus-tainability of our First World economy, especially when we reflect howquickly Chaco society collapsed after its peak in the decade A.D. 1110-1120,and how implausible the risk of collapse would have seemed to Chacoans ofthat decade.Within our five-factor framework for understanding societal collapses,four of those factors played a role in the Anasazi collapse. There were indeedhuman environmental impacts of several types, especially deforestation andarroyo cutting. There was also climate change in rainfall and temperature,and its effects interacted with the effects of human environmental impacts.Internal trade with friendly trade partners did play a crucial role in the col-lapse: different Anasazi groups supplied food, timber, pottery, stone, andluxury goods to each other, supporting each other in an interdependentcomplex society, but putting the whole society at risk of collapsing. Reli-gious and political factors apparently played an essential role in sustainingthe complex society, by coordinating the exchanges of materials, and bymotivating people in outlying areas to supply food, timber, and pottery tothe political and religious centers. The only factor in our five-factor list forwhose operation there is not convincing evidence in the case of the Anasazicollapse is external enemies. While the Anasazi did indeed attack each otheras their population grew and as the climate deteriorated, the civilizations ofthe U.S. Southwest were too distant from other populous societies to havebeen seriously threatened by any external enemies.From that perspective, we can propose a simple answer to the long-standing either/or debate: was Chaco Canyon abandoned because of hu-man impact on the environment, or because of drought? The answer is: itwas abandoned for both reasons. Over the course of six centuries the hu-man population of Chaco Canyon grew, its demands on the environmentgrew, its environmental resources declined, and people came to be living in-creasingly close to the margin of what the environment could support. Thatwas the ultimate cause of abandonment. The proximate cause, the prover-bial last straw that broke the camel's back, was the drought that finallypushed Chacoans over the edge, a drought that a society living at a lowerpopulation density could have survived. When Chaco society did collapse,its inhabitants could no longer reconstruct their society in the way that thefirst farmers of the Chaco area had built up their society. The reason is thatthe initial conditions of abundant nearby trees, high groundwater levels,and a smooth floodplain without arroyos had disappeared.That type of conclusion is likely to apply to many other collapses of pastsocieties (including the Maya to be considered in the next chapter), and toour own destiny today. All of us moderns—house-owners, investors, politi-cians, university administrators, and others—can get away with a lot ofwaste when the economy is good. We forget that conditions fluctuate,and we may not be able to anticipate when conditions will change. By thattime, we may already have become attached to an expensive lifestyle, leavingan enforced diminished lifestyle or bankruptcy as the sole outs.C H A P T E R 5The Maya CollapsesMysteries of lost cities The Maya environment Maya agriculture Maya history Copan * Complexities of collapses Wars anddroughts Collapse in the southern lowlands The Maya messagey now, millions of modern tourists have visited ruins of the ancientMaya civilization that collapsed over a thousand years ago in Mexico'sYucatan Peninsula and adjacent parts of Central America. All of usframework is climate change, aterm that today we tend to associate with global warming caused by hu-mans. In fact, climate may become hotter or colder, wetter or drier, or moreor less variable between months or between years, because of changes innatural forces that drive climate and that have nothing to do with humans.Examples of such forces include changes in the heat put out by the sun,volcanic eruptions that inject dust into the atmosphere, changes in the ori-entation of the Earth's axis with respect to its orbit, and changes in the dis-tribution of land and ocean over the face of the Earth. Frequently discussedcases of natural climate change include the advance and retreat of continen-tal ice sheets during the Ice Ages beginning over two million years ago, theso-called Little Ice Age from about A.D. 1400 to 1800, and the global coolingfollowing the enormous volcanic eruption of Indonesia's Mt. Tambora onApril 5, 1815. That eruption injected so much dust into the upper atmo-sphere that the amount of sunlight reaching the ground decreased until thedust settled out, causing widespread famines even in North America andEurope due to cold temperatures and reduced crop yields in the summerof 1816 ("the year without a summer").Climate change was even more of a problem for past societies with shorthuman lifespans and without writing than it is today, because climate inmany parts of the world tends to vary not just from year to year but also ona multi-decade time scale; e.g., several wet decades followed by a dry half-century. In many prehistoric societies the mean human generation time—average number of years between births of parents and of their children—was only a few decades. Hence towards the end of a string of wet decades,most people alive could have had no firsthand memory of the previousperiod of dry climate. Even today, there is a human tendency to increaseproduction and population during good decades, forgetting (or, in the past,never realizing) that such decades were unlikely to last. When the gooddecades then do end, the society finds itself with more population thancan be supported, or with ingrained habits unsuitable to the new climateconditions. (Just think today of the dry U.S. West and its urban or ruralpolicies of profligate water use, often drawn up in wet decades on the tacitassumption that they were typical.) Compounding these problems ofclimate change, many past societies didn't have "disaster relief" mechanismsto import food surpluses from other areas with a different climate into areasdeveloping food shortages. All of those considerations exposed past soci-eties to increased risk from climate change.Natural climate changes may make conditions either better or worse forany particular human society, and may benefit one society while hurtinganother society. (For example, we shall see that the Little Ice Age was bad forthe Greenland Norse but good for the Greenland Inuit.) In many historicalcases, a society that was depleting its environmental resources could absorbthe losses as long as the climate was benign, but was then driven over thebrink of collapse when the climate became drier, colder, hotter, wetter, ormore variable. Should one then say that the collapse was caused by humanenvironmental impact, or by climate change? Neither of those simple alter-natives is correct. Instead, if the society hadn't already partly depleted its en-vironmental resources, it might have survived the resource depletion causedby climate change. Conversely, it was able to survive its self-inflicted re-source depletion until climate change produced further resource depletion.It was neither factor taken alone, but the combination of environmental im-pact and climate change, that proved fatal.A third consideration is hostile neighbors. All but a few historical soci-eties have been geographically close enough to some other societies to havehad at least some contact with them. Relations with neighboring societiesmay be intermittently or chronically hostile. A society may be able to holdoff its enemies as long as it is strong, only to succumb when it becomesweakened for any reason, including environmental damage. The proximatecause of the collapse will then be military conquest, but the ultimatecause-—the factor whose change led to the collapse—will have been the fac-tor that caused the weakening. Hence collapses for ecological or other rea-sons often masquerade as military defeats.The most familiar debate about such possible masquerading involvesthe fall of the Western Roman Empire. Rome became increasingly beset bybarbarian invasions, with the conventional date for the Empire's fall beingtaken somewhat arbitrarily as A.D. 476, the year in which the last emperor ofthe West was deposed. However, even before the rise of the Roman Empire,there had been "barbarian" tribes who lived in northern Europe and CentralAsia beyond the borders of "civilized" Mediterranean Europe, and who pe-riodically attacked civilized Europe (as well as civilized China and India).For over a thousand years, Rome successfully held off the barbarians, for in-stance slaughtering a large invading force of Cimbri and Teutones bent onconquering northern Italy at the Battle of Campi Raudii in 101 B.C.Eventually, it was the barbarians rather than Romans who won the bat-tles: what was the fundamental reason for that shift in fortune? Was it be-cause of changes in the barbarians themselves, such that they became morenumerous or better organized, acquired better weapons or more horses, orprofited from climate change in the Central Asian steppes? In that case, wewould say that barbarians really could be identified as the fundamentalcause of Rome's fall. Or was it instead that the same old unchanged barbar-ians were always waiting on the Roman Empire's frontiers, and that theycouldn't prevail until Rome became weakened by some combination of eco-nomic, political, environmental, and other problems? In that case we wouldblame Rome's fall on its own problems, with the barbarians just providingthe coup de grace. This question continues to be debated. Essentially thesame question has been debated for the fall of the Khmer Empire centeredon Angkor Wat in relation to invasions by Thai neighbors, for the decline inHarappan Indus Valley civilization in relation to Aryan invasions, and forthe fall of Mycenean Greece and other Bronze Age Mediterranean societiesin relation to invasions by Sea Peoples.The fourth set of factors is the converse of the third set: decreased sup-port by friendly neighbors, as opposed to increased attacks by hostile neigh-bors. All but a few historical societies have had friendly trade partners aswell as neighboring enemies. Often, the partner and the enemy are one andthe same neighbor, whose behavior shifts back and forth between friendlyand hostile. Most societies depend to some extent on friendly neighbors, ei-ther for imports of essential trade goods (like U.S. imports of oil, and Japa-nese imports of oil, wood, and seafood, today), or else for cultural ties thatlend cohesion to the society (such as Australia's cultural identity importedfrom Britain until recently). Hence the risk arises that, if your trade partnerbecomes weakened for any reason (including environmental damage) andcan no longer supply the essential import or the cultural tie, your own soci-ety may become weakened as a result. This is a familiar problem today be-cause of the First World's dependence on oil from ecologically fragile andpolitically troubled Third World countries that imposed an oil embargo in1973. Similar problems arose in the past for the Greenland Norse, PitcairnIslanders, and other societies.The last set of factors in my five-point framework involves the ubiqui-tous question of the society's responses to its problems, whether thoseproblems are environmental or not. Different societies respond differentlyto similar problems.love a romantic mystery, and the Maya offer us one at our doorstep, almostas close for Americans as the Anasazi ruins. To visit a former Maya city, weneed only board a direct flight from the U.S. to the modern Mexican statecapital city of Merida, jump into a rental car or minibus, and drive an houron a paved highway (map, p. 161).Today, many Maya ruins, with their great temples and monuments, stilllie surrounded by jungle, far from current human settlement (Plate 12). Yetthey were once the sites of the New World's most advanced Native Ameri-can civilization before European arrival, and the only one with extensive de-ciphered written texts. How could ancient peoples have supported urbansocieties in areas where few farmers eke out a living today? The Maya citiesimpress us not only with that mystery and with their beauty, but also be-cause they are "pure" archaeological sites. That is, their locations becamedepopulated, so they were not covered up by later buildings as were somany other ancient cities, like the Aztec capital of Tenochtitlan (now buriedunder modern Mexico City) and Rome.Maya cities remained deserted, hidden by trees, and virtually unknownto the outside world until rediscovered in 1839 by a rich American law-yer named John Stephens, together with the English draftsman FrederickCatherwood. Having heard rumors of ruins in the jungle, Stephens gotPresident Martin Van Buren to appoint him ambassador to the Confedera-tion of Central American Republics, an amorphous political entity thenextending from modern Guatemala to Nicaragua, as a front for his archaeo-logical explorations. Stephens and Catherwood ended up exploring 44 sitesand cities. From the extraordinary quality of the buildings and the art, theyBrealized that these were not the work of savages (in their words) but of avanished high civilization. They recognized that some of the carvings on thestone monuments constituted writing, and they correctly guessed that it re-lated historical events and the names of people. On his return, Stephenswrote two travel books, illustrated by Catherwood and describing the ruins,that became best sellers.A few quotes from Stephens's writings will give a sense of the romanticappeal of the Maya: "The city was desolate. No remnant of this race hangsround the ruins, with traditions handed down from father to son and fromgeneration to generation. It lay before us like a shattered bark in the midstof the ocean, her mast gone, her name effaced, her crew perished, and noneto tell whence she came, to whom she belonged, how long on her journey,or what caused her destruction.... Architecture, sculpture, and painting, allthe arts which embellish life, had flourished in this overgrown forest; ora-tors, warriors, and statesmen, beauty, ambition, and glory had lived andpassed away, and none knew that such things had been, or could tell of theirpast existence.... Here were the remains of a cultivated, polished, and pe-culiar people, who had passed through all the stages incident to the rise andfall of nations; reached their golden age, and perished.... We went up totheir desolate temples and fallen altars; and wherever we moved we saw theevidence of their taste, their skill in arts. ... We called back into life thestrange people who gazed in sadness from the wall; pictured them, in fanci-ful costumes and adorned with plumes of feather, ascending the terraces ofthe palace and the steps leading to the temples.... In the romance of theworld's history nothing ever impressed me more forcibly than the spectacleof this once great and lovely city, overturned, desolate, and lost,... over-grown with trees for miles around, and without even a name to distinguishit." Those sensations are what tourists drawn to Maya ruins still feel today,and why we find the Maya collapse so fascinating.The Maya story has several advantages for all of us interested in prehis-toric collapses. First, the Maya written records that have survived, althoughfrustratingly incomplete, are still useful for reconstructing Maya history inmuch greater detail than we can reconstruct Easter Island, or even Anasazihistory with its tree rings and packrat middens. The great art and architec-ture of Maya cities have resulted in far more archaeologists studying theMaya than would have been the case if they had just been illiterate hunter-gatherers living in archaeologically invisible hovels. Climatologists and pa-leoecologists have recently been able to recognize several signals of ancientclimate and environmental changes that contributed to the Maya collapse.Finally, today there are still Maya people living in their ancient homelandand speaking Maya languages. Because much ancient Maya culture survivedthe collapse, early European visitors to the homeland recorded informationabout contemporary Maya society that played a vital role in our under-standing ancient Maya society. The first Maya contact with Europeans camealready in 1502, just 10 years after Christopher Columbus's "discovery" ofthe New World, when Columbus on the last of his four voyages captured atrading canoe that may have been Maya. In 1527 the Spanish began inearnest to conquer the Maya, but it was not until 1697 that they subduedthe last principality. Thus, the Spanish had opportunities to observe inde-pendent Maya societies for a period of nearly two centuries. Especially im-portant, both for bad and for good, was the bishop Diego de Landa, whoresided in the Yucatan Peninsula for most of the years from 1549 to 1578.On the one hand, in one of history's worst acts of cultural vandalism, heburned all Maya manuscripts that he could locate in his effort to eliminate"paganism," so that only four survive today. On the other hand, he wrote adetailed account of Maya society, and he obtained from an informant a gar-bled explanation of Maya writing that eventually, nearly four centuries later,turned out to offer clues to its decipherment.A further reason for our devoting a chapter to the Maya is to provide anantidote to our other chapters on past societies, which consist dispropor-tionately of small societies in somewhat fragile and geographically isolatedenvironments, and behind the cutting edge of contemporary technologyand culture. The Maya were none of those things. Instead, they were cultur-ally the most advanced society (or among the most advanced ones) in thepre-Columbian New World, the only one with extensive preserved writing,and located within one of the two heartlands of New World civilization(Mesoamerica). While their environment did present some problems asso-ciated with its karst terrain and unpredictably fluctuating rainfall, it doesnot rank as notably fragile by world standards, and it was certainly less frag-ile than the environments of ancient Easter Island, the Anasazi area, Green-land, or modern Australia. Lest one be misled into thinking that crashes area risk only for small peripheral societies in fragile areas, the Maya warn usthat crashes can also befall the most advanced and creative societies.From the perspective of our five-point framework for understanding so-cietal collapses, the Maya illustrate four of our points. They did damagetheir environment, especially by deforestation and erosion. Climate changes(droughts) did contribute to the Maya collapse, probably repeatedly. Hos-tilities among the Maya themselves did play a large role. Finally, political/cultural factors, especially the competition among kings and nobles that ledto a chronic emphasis on war and erecting monuments rather than on solv-ing underlying problems, also contributed. The remaining item on our five-point list, trade or cessation of trade with external friendly societies, doesnot appear to have been essential in sustaining the Maya or in causing theirdownfall. While obsidian (their preferred raw material for making intostone tools), jade, gold, and shells were imported into the Maya area,For instance, problems of deforestation arose for manypast societies, among which Highland New Guinea, Japan, Tikopia, andTonga developed successful forest management and continued to prosper,while Easter Island, Mangareva, and Norse Greenland failed to develop suc-cessful forest management and collapsed as a result. How can we under-stand such differing outcomes? A society's responses depend on its political,economic, and social institutions and on its cultural values. Those institu-tions and values affect whether the society solves (or even tries to solve) itsproblems. In this book we shall consider this five-point framework for eachpast society whose collapse or persistence is discussed.I should add, of course, that just as climate change, hostile neighbors,and trade partners may or may not contribute to a particular society's col-lapse, environmental damage as well may or may not contribute. It wouldbe absurd to claim that environmental damage must be a major factor in allcollapses: the collapse of the Soviet Union is a modern counter-example,and the destruction of Carthage by Rome in 146 B.C. is an ancient one. It'sobviously true that military or economic factors alone may suffice. Hence afull title for this book would be "Societal collapses involving an environ-mental component, and in some cases also contributions of climate change,hostile neighbors, and trade partners, plus questions of societal responses."That restriction still leaves us ample modern and ancient material toconsider.Issues of human environmental impacts today tend to be controversial, andopinions about them tend to fall on a spectrum between two opposite camps.One camp, usually referred to as "environmentalist" or "pro-environment,"holds that our current environmental problems are serious and in urgentneed of addressing, and that current rates of economic and populationgrowth cannot be sustained. The other camp holds that environmentalists'concerns are exaggerated and unwarranted, and that continued economicand population growth is both possible and desirable. The latter camp isn'tassociated with an accepted short label, and so I shall refer to it simply as"non-environmentalist." Its adherents come especially from the world of bigbusiness and economics, but the equation "non-environmentalist" = "pro-business" is imperfect; many businesspeople consider themselves environ-mentalists, and many people skeptical of environmentalists' claims are notin the world of big business. In writing this book, where do I stand myselfwith the respect to these two camps?On the one hand, I have been a bird-watcher since I was seven years old.I trained professionally as a biologist, and I have been doing research onNew Guinea rainforest birds for the past 40 years. I love birds, enjoy watch-mg them, and enjoy being in rainforest. I also like other plants, animals, andhabitats and value them for their own sakes. I've been active in many effortsto preserve species and natural environments in New Guinea and elsewhere.For the past dozen years I've been a director of the U.S. affiliate of WorldWildlife Fund, one of the largest international environmentalist organiza-tions and the one with the most cosmopolitan interests. All of those thingshave earned me criticism from non-environmentalists, who use phrasessuch as "fearmonger," "Diamond preaches gloom and doom," "exaggeratesrisks," and "favors endangered purple louseworts over the needs of people."But while I do love New Guinea birds, I love much more my sons, my wife,my friends, New Guineans, and other people. I'm more interested in envi-ronmental issues because of what I see as their consequences for peoplethan because of their consequences for birds.On the other hand, I have much experience, interest, and ongoing in-volvement with big businesses and other forces in our society that exploitenvironmental resources and are often viewed as anti-environmentalist. Asa teenager, I worked on large cattle ranches in Montana, to which, as anadult and father, I now regularly take my wife and my sons for summer va-cations. I had a job on a crew of Montana copper miners for one summer. Ilove Montana and my rancher friends, I understand and admire and sym-pathize with their agribusinesses and their lifestyles, and I've dedicated thisbook to them. In recent years I've also had much opportunity to observeand become familiar with other large extractive companies in the mining,logging, fishing, oil, and natural gas industries. For the last seven years I'vebeen monitoring environmental impacts in Papua New Guinea's largestproducing oil and natural gas field, where oil companies have engagedWorld Wildlife Fund to provide independent assessments of the environ-ment. I have often been a guest of extractive businesses on their properties,I've talked a lot with their directors and employees, and I've come to under-stand their own perspectives and problems.While these relationships with big businesses have given me close-upviews of the devastating environmental damage that they often cause, I'vealso had close-up views of situations where big businesses found it in theirinterests to adopt environmental safeguards more draconian and effectivethan I've encountered even in national parks. I'm interested in what moti-vates these differing environmental policies of different businesses. Myinvolvement with large oil companies in particular has brought me con-demnation from some environmentalists, who use phrases such as "Dia-mond has sold out to big business," "He's in bed with big businesses," or "Heprostitutes himself to the oil companies."In fact, I am not hired by big businesses, and I describe frankly what Isee happening on their properties even though I am visiting as their guest.On some properties I have seen oil companies and logging companies beingdestructive, and I have said so; on other properties I have seen them beingcareful, and that was what I said. My view is that, if environmentalists aren'twilling to engage with big businesses, which are among the most powerfulforces in the modern world, it won't be possible to solve the world's envi-ronmental problems. Thus, I am writing this book from a middle-of-the-road perspective, with experience of both environmental problems and ofbusiness realities.How can one study the collapses of societies "scientifically"? Science is oftenmisrepresented as "the body of knowledge acquired by performing repli-cated controlled experiments in the laboratory." Actually, science is some-thing much broader: the acquisition of reliable knowledge about the world.In some fields, such as chemistry and molecular biology, replicated con-trolled experiments in the laboratory are feasible and provide by far themost reliable means to acquire knowledge. My formal training was in twosuch fields of laboratory biology, biochemistry for my undergraduate de-gree and physiology for my Ph.D. From 1955 to 2002 I conducted experi-mental laboratory research in physiology, at Harvard University and then atthe University of California in Los Angeles.When I began studying birds in New Guinea rainforest in 1964, I wasimmediately confronted with the problem of acquiring reliable knowledgewithout being able to resort to replicated controlled experiments, whetherin the laboratory or outdoors. It's usually neither feasible, legal, nor ethicalto gain knowledge about birds by experimentally exterminating or manipu-lating their populations at one site while maintaining their populations atanother site as unmanipulated controls. I had to use different methods.Similar methodological problems arise in many other areas of populationbiology, as well as in astronomy, epidemiology, geology, and paleontology.A frequent solution is to apply what is termed the "comparativemethod" or the "natural experiment"—i.e., to compare natural situationsdiffering with respect to the variable of interest. Forinstance, when I as anornithologist am interested in effects of New Guinea's Cinnamon-browedMelidectes Honeyeater on populations of other honeyeater species, I com-pare bird communities on mountains that are fairly similar except thatsome do and others don't happen to support populations of Cinnamon-browed Melidectes Honeyeaters. Similarly, my books The Third Chim-panzee: The Evolution and Future of the Human Animal and Why Is Sex Fun?The Evolution of Human Sexuality compared different animal species, espe-cially different species of primates, in an effort to figure out why women(unlike females of most other animal species) undergo menopause and lackobvious signs of ovulation, why men have a relatively large penis (by animalstandards), and why humans usually have sex in private (rather than in theopen, as almost all other animal species do). There is a large scientific litera-ture on the obvious pitfalls of that comparative method, and on how best toovercome those pitfalls. Especially in historical sciences (like evolutionarybiology and historical geology), where it's impossible to manipulate the pastexperimentally, one has no choice except to renounce laboratory experi-ments in favor of natural ones.This book employs the comparative method to understand societalcollapses to which environmental problems contribute. My previous book(Guns, Germs, and Steel: The Fates of Human Societies) had applied thecomparative method to the opposite problem: the differing rates of buildupof human societies on different continents over the last 13,000 years. Inthe present book focusing instead on collapses rather than on buildups, Icompare many past and present societies that differed with respect to en-vironmental fragility, relations with neighbors, political institutions, andother "input" variables postulated to influence a society's stability. The"output" variables that I examine are collapse or survival, and form of thecollapse if a collapse does occur. By relating output variables to inputvariables, I aim to tease out the influence of possible input variables oncollapses.A rigorous, comprehensive, and quantitative application of this methodwas possible for the problem of deforestation-induced collapses on Pacificislands. Prehistoric Pacific peoples deforested their islands to varying de-grees, ranging from only slight to complete deforestation, and with societaloutcomes ranging from long-term persistence to complete collapses thatleft everybody dead. For 81 Pacific islands my colleague Barry Rolett and Igraded the extent of deforestation on a numerical scale, and we also gradedvalues of nine input variables (such as rainfall, isolation, and restoration ofsoil fertility) postulated to influence deforestation. By a statistical analysiswe were able to calculate the relative strengths with which each input vari-able predisposed the outcome to deforestation. Another comparative ex-periment was possible in the North Atlantic, where medieval Vikings fromNorway colonized six islands or land masses differing in suitability for agri-culture, ease of trade contact with Norway, and other input variables, andalso differing in outcome (from quick abandonment, to everybody dead af-ter 500 years, to still thriving after 1,200 years). Still other comparisons arepossible between societies from different parts of the world.All of these comparisons rest on detailed information about individualsocieties, patiently accumulated by archaeologists, historians, and otherscholars. At the end of this book I provide references to the many excellentbooks and papers on the ancient Maya and Anasazi, the modern Rwandansand Chinese, and the other past and present societies that I compare. Thoseindividual studies constitute the indispensable database for my book. Butthere are additional conclusions that can be drawn from comparisonsamong those many societies, and that could not have been drawn from de-tailed study of just a single society. For example, to understand the famousMaya collapse requires not only accurate knowledge of Maya history andthe Maya environment; we can place the Maya in a broader context andgain further insights by comparing them with other societies that did ordidn't collapse, and that resembled the Maya in some respects and differedfrom them in other respects. Those further insights require the comparativemethod.I have belabored this necessity for both good individual studies andgood comparisons, because scholars practicing one approach too often be-little the contributions of the other approach. Specialists in the history ofone society tend to dismiss comparisons as superficial, while those whocompare tend to dismiss studies of single societies as hopelessly myopic andof limited value for understanding other societies. But we need both typesof studies if we are to acquire reliable knowledge. In particular, it would bedangerous to generalize from one society, or even just to be confident aboutinterpreting a single collapse. Only from the weight of evidence providedby a comparative study of many societies with different outcomes can onehope to reach convincing conclusions.So that readers will have some advance idea where they are heading, here ishow this book is organized. Its plan resembles a boa constrictor that hasswallowed two very large sheep. That is, my discussions of the modernworld and also of the past both consist of a disproportionately long accountof one society, plus briefer accounts of four other societies.We shall begin with the first large sheep. Part One comprises a singlelengthy chapter (Chapter 1), on the environmental problems of southwest-ern Montana, where Huls Farm and the ranches of my friends the HirschysI to whom this book is dedicated) are located. Montana has the advantage ofbeing a modern First World society whose environmental and populationproblems are real but still relatively mild compared to those of most of therest of the First World. Above all, I know many Montanans well, so that Ican connect the policies of Montana society to the often-conflicting moti-vations of individual people. From that familiar perspective of Montana, wecan more easily imagine what was happening in the remote past societiesthat initially strike us as exotic, and where we can only guess what moti-vated individual people.Part Two begins with four briefer chapters on past societies that didcollapse, arranged in a sequence of increasing complexity according to myfive-point framework. Most of the past societies that I shall discuss in detailwere small and peripherally located, and some were geographically bounded,or socially isolated, or in fragile environments. Lest the reader thereby bemisled into concluding that they are poor models for familiar big modernsocieties, I should explain that I selected them for close consideration pre-cisely because processes unfolded faster and reached more extreme out-comes in such small societies, making them especially clear illustrations. Itis not the case that large central societies trading with neighbors and locatedin robust environments didn't collapse in the past and can't collapse today.One of the past societies that I do discuss in detail, the Maya, had a popula-tion of many millions or tens of millions, was located within one of thetwo most advanced cultural areas of the New World before European arrival(Mesoamerica), and traded with and was decisively influenced by other ad-vanced societies in that area. I briefly summarize in the Further Readingssection for Chapter 9 some of the many other famous past societies—Fertile Crescent societies, Angkor Wat, Harappan Indus Valley society, andothers—that resembled the Maya in those respects, and to whose declinesenvironmental factors contributed heavily.Our first case study from the past, the history of Easter Island (Chapter2), is as close as we can get to a "pure" ecological collapse, in this casedue tototal deforestation that led to war, overthrow of the elite and of the fa-mous stone statues, and a massive population die-off. As far as we know,Easter's Polynesian society remained isolated after its initial founding, sothat Easter's trajectory was uninfluenced by either enemies or friends. Nordo we have evidence of a role of climate change on Easter, though that couldstill emerge from future studies. Barry Rolett's and my comparative analysishelps us understand why Easter, of all Pacific islands, suffered such a severecollapse.Pitcairn Island and Henderson Island (Chapter 3), also settled by Poly-nesians, offer examples of the effect of item four of my five-point frame-work: loss of support from neighboring friendly societies. Both Pitcairn andHenderson islands suffered local environmental damage, but the fatal blowcame from the environmentally triggered collapse of their major trade part-ner. There were no known complicating effects of hostile neighbors or ofclimate change.Thanks to an exceptionally detailed climate record reconstructed fromtree rings, the Native American society of the Anasazi in the U.S. Southwest(Chapter 4) clearly illustrates the intersection of environmental damageand population growth with climate change (in this case, drought). Neitherfriendly or hostile neighbors, nor (except towards the end) warfare, appearto have been major factors in the Anasazi collapse.No book on societal collapses would be complete without an account(Chapter 5) of the Maya, the most advanced Native American society andthe quintessential romantic mystery of cities covered by jungle. As in thecase of the Anasazi, the Maya illustrate the combined effects of environ-mental damage, population growth, and climate change without an essen-tial role of friendly neighbors. Unlike the case with the Anasazi collapse,hostile neighbors were a major preoccupation of Maya cities already froman early stage. Among the societies discussed in Chapters 2 through 5, onlythe Maya offer us the advantage of a deciphered written record.Norse Greenland (Chapters 6-8) offers us our most complex case of aprehistoric collapse, the one for which we have the most information (be-cause it was a well-understood literate European society), and the one war-ranting the most extended discussion: the second sheep inside the boaconstrictor. All five items in my five-point framework are well documented:environmental damage, climate change, loss of friendly contacts with Nor-way, rise of hostile contacts with the Inuit, and the political, economic, so-cial, and cultural setting of the Greenland Norse. Greenland provides uswith our closest approximation to a controlled experiment in collapses: twosocieties (Norse and Inuit) sharing the same island, but with very differentcultures, such that one of those societies survived while the other was dying.Thus, Greenland history conveys the message that, even in a harsh environ-ment, collapse isn't inevitable but depends on a society's choices. Com-parisons are also possible between Norse Greenland and five other NorthAtlantic societies founded by Norse colonists, to help us understand whythe Orkney Norse thrived while their Greenland cousins were succumbing.One of those five other Norse societies, Iceland, ranks as an outstandingsuccess story of triumph over a fragile environment to achieve a high levelof modern prosperity.Part Two concludes (Chapter 9) with three more societies that (like Ice-land) succeeded, as contrast cases for understanding societies that failed.While those three faced less severe environmental problems than Iceland orthan most of those that failed, we shall see that there are two different pathsto success: a bottom-up approach exemplified by Tikopia and the NewGuinea highlands, and a top-down approach exemplified by Japan of theTokugawa Era.Part Three then returns to the modern world. Having already consid-ered modern Montana in Chapter 2, we now take up four markedly differ-ent modern countries, the first two small and the latter two large or huge: aThird World disaster (Rwanda), a Third World survivor-so-far (the Do-minican Republic), a Third World giant racing to catch up with the FirstWorld (China), and a First World society (Australia). Rwanda (Chapter 10)represents a Malthusian catastrophe happening under our eyes, an over-populated land that collapsed in horrible bloodshed, as the Maya did in thepast. Rwanda and neighboring Burundi are notorious for their Hutu/Tutsiethnic violence, but we shall see that population growth, environmentaldamage, and climate change provided the dynamite for which ethnic vio-lence was the fuse.The Dominican Republic and Haiti (Chapter 11), sharing the island ofHispaniola, offer us a grim contrast, as did Norse and Inuit societies inGreenland. From decades of equally vile dictatorships, Haiti emerged as themodern New World's saddest basket case, while there are signs of hope inthe Dominican Republic. Lest one suppose that this book preaches environ-mental determinism, the latter country illustrates what a big difference oneperson can make, especially if he or she is the country's leader.China (Chapter 12) suffers from heavy doses of all 12 modern types ofenvironmental problems. Because China is so huge in its economy, popula-tion, and area, China's environmental and economic impact is importantnot only for China's own people but also for the whole world.Australia (Chapter 13) is at the opposite extreme from Montana, as theFirst World society occupying the most fragile environment and experienc-ing the most severe environmental problems. As a result, it is also amongthe countries now considering the most radical restructuring of its society,in order to solve those problems.This book's concluding section (Part Four) extracts practical lessons forus today. Chapter 14 asks the perplexing question arising for every past so-ciety that ended up destroying itself, and that will perplex future earthlingsif we too end up destroying ourselves: how could a society fail to have seenthe dangers that seem so clear to us in retrospect? Can we say that their endwas the inhabitants' own fault, or that they were instead tragic victims of in-soluble problems? How much past environmental damage was uninten-tional and imperceptible, and how much was perversely wrought by peopleacting in full awareness of the consequences? For instance, what were EasterIslanders saying as they cut down the last tree on their island? It turns outthat group decision-making can be undone by a whole series of factors, be-ginning with failure to anticipate or perceive a problem, and proceedingthrough conflicts of interest that leave some members of the group to pur-sue goals good for themselves but bad for the rest of the group.Chapter 15 considers the role of modern businesses, some of which areamong the most environmentally destructive forces today, while others pro-vide some of the most effective environmental protection. We shall examinewhy some (but only some) businesses find it in their interests to be protec-tive, and what changes would be necessary before other businesses wouldfind it in their interests to emulate them.Finally, Chapter 16 summarizes the types of environmental dangers fac-ing the modern world, the commonest objections raised against claims oftheir seriousness, and differences between environmental dangers todayand those faced by past societies. A major difference has to do with global-ization, which lies at the heart of the strongest reasons both for pessimismand for optimism about our ability to solve our current environmentalproblems. Globalization makes it impossible for modern societies to col-lapse in isolation, as did Easter Island and the Greenland Norse in the past.Any society in turmoil today, no matter how remote—think of Somalia andAfghanistan as examples—can cause trouble for prosperous societies onother continents,and is also subject to their influence (whether helpful ordestabilizing). For the first time in history, we face the risk of a global de-cline. But we also are the first to enjoy the opportunity of learning quicklyfrom developments in societies anywhere else in the world today, and fromwhat has unfolded in societies at any time in the past. That's why I wrotethis book.PART ONEM O D E R NM O N T A N AC H A P T E R 1Under Montana's Big SkyStan Falkow's story m Montana and me Why begin with Montana? Montana's economic history it Mining Forests Soil Water Native and non-native species Differing visions Attitudes towards regulation Rick Laible's story Chip Pigman's story 11 Tim Huls's story John Cook's story Montana, model of the worldhen I asked my friend Stan Falkow, a 70-year-old professor of mi-crobiology at Stanford University near San Francisco, why hehad bought a second home in Montana's Bitterroot Valley, hetold me how it had fitted into the story of his life:"I was born in New York State and then moved to Rhode Island. Thatmeant that, as a child, I knew nothing about mountains. While I was in myearly 20s, just after graduating college, I took off a couple of years from myeducation to work on the night shift in a hospital autopsy room. For ayoung person like myself without previous experience of death, it was verystressful. A friend who had just returned from the Korean War and had seena lot of stress there took one look at me and said, 'Stan, you look nervous;you need to reduce your stress level. Try fly-fishing!'"So I started fly-fishing to catch bass. I learned how to tie my own flies,really got into it, and went fishing every day after work. My friend was right:it did reduce stress. But then I entered graduate school in Rhode Island andgot into another stressful work situation. A fellow graduate student told methat bass weren't the only fish that one could catch by fly-fishing: I couldalso fly-fish for trout nearby in Massachusetts. So I took up trout-fishing.My thesis supervisor loved to eat fish, and he encouraged me to go fishing:those were the only occasions when he didn't frown at my taking time offfrom work in the laboratory."Around the time that I turned 50, it was another stressful period of mylife, because of a difficult divorce and other things. By then, I was taking offtime to go fly-fishing only three times a year. Fiftieth birthdays make manyof us reflect on what we want to do with what's left of our lives. I reflectedwon my own father's life, and I remembered that he had died at age 58.1 real-ized with a jolt that, if I were to live only as long as he did, I could count ononly 24 more fly-fishing trips before I died. That felt like very few times todo something that I enjoyed so much. The realization made me start think-ing about how I could spend more of my time doing what I really likedduring the years that I had left, including fly-fishing."At that point, I happened to be asked to go evaluate a research labora-tory in the Bitterroot Valley of southwestern Montana. I had never been toMontana before; in fact, I had never even been west of the Mississippi Riveruntil I was 40 years old. I flew into Missoula airport, picked up a rental car,and began to drive south to the town of Hamilton where the lab was lo-cated. A dozen miles south of Missoula is a long straight stretch of roadwhere the valley floor is flat and covered with farmland, and where thesnowcapped Bitterroot Mountains on the west and the Sapphire Mountainson the east rise abruptly from the valley. I was overwhelmed by the beautyand scale of it; I had never seen anything like it before. It filled me with asense of peace, and with an extraordinary perspective on my place in theworld."When I arrived at the lab, I ran into a former student of mine who wasworking there and knew about my interest in fly-fishing. He suggested that Icome back the next year to do some experiments at the lab, and also to gofly-fishing for trout, for which the Bitterroot River is famous. So I returnedthe next summer with the intention of spending two weeks, and I ended upstaying a month. The summer after that, I came intending to stay a monthand ended up staying for the whole summer, at the end of which my wifeand I bought a house in the valley. We have been coming back ever since,spending a large part of each year in Montana. Every time I return to theBitterroot, when I enter it on that stretch of road south of Missoula, thatfirst sight of the valley fills me again with that same feeling of tranquilityand grandeur, and that same perspective on my relation to the universe. It'seasier to preserve that sense in Montana than anywhere else."That's what the beauty of Montana does to people: both to those who hadgrown up in places completely unlike it, like Stan Falkow and me; to otherfriends, like John Cook, who grew up in other mountainous areas of theAmerican West but still found themselves drawn to Montana; and to stillother friends, like the Hirschy family, who did grow up in Montana andchose to stay there.Like Stan Falkow, I was born in the northeastern U.S. (Boston) and hadnever been west of the Mississippi until the age of 15, when my parents tookme to spend a few weeks of the summer in the Big Hole Basin just south ofthe Bitterroot Valley (map, p. 31). My father was a pediatrician who hadtaken care of a ranchers' child, Johnny Eliel, afflicted by a rare disease forwhich his family pediatrician in Montana had recommended that he go toBoston for specialty treatment. Johnny was a great-grandson of FredHirschy Sr., a Swiss immigrant who became one of the pioneer ranchers inthe Big Hole in the 1890s. His son Fred Jr., by the time of my visit 69 yearsold, was still running the family ranch, along with his grown sons Dick andJack Hirschy and his daughters Jill Hirschy Eliel (Johnny's mother) and JoyceHirschy McDowell. Johnny did well under my father's treatment, and so hisparents and grandparents invited our family to come visit them.Also like Stan Falkow, I was immediately overwhelmed by the Big Hole'ssetting: a broad flat valley floor covered with meadows and meanderingcreeks, but surrounded by a wall of seasonally snow-covered mountains ris-ing abruptly on every horizon. Montana calls itself the "Big Sky State." It'sreally true. In most other places where I've lived, either one's view of thelower parts of the sky is obscured by buildings, as in cities; or else there aremountains but the terrain is rugged and the valleys are narrow, so one seesonly a slice of the sky, as in New Guinea and the Alps; or else there is a broadexpanse of sky but it's less interesting, because there is no ring of distinctivemountains on the horizon—as on the plains of Iowa and Nebraska. Threeyears later, while I was a student in college, I came back for the summer toDick Hirschy's ranch with two college friends and my sister, and we allworked for the Hirschys on the hay harvest, I driving a scatterrake, my sistera buckrake, and my two friends stacking hay.After that summer of 1956, it was a long time before I returned to Mon-tana. I spent my summers in other places that were beautiful in other ways,such as New Guinea and the Andes, but I couldn't forget Montana or theHirschys. Finally, in 1998 I happened to receive an invitation from a privatenon-profit foundation called the Teller Wildlife Refuge in the BitterrootValley. It was an opportunity to bring my own twin sons to Montana, at anage only a few years younger than the age at which I had first visited thestate, and to introduce them to fly-fishing for trout. My boys took to it; one°f them is now learning to be a fishing guide. I reconnected to Montana andrevisited my rancher boss Dick Hirschy and his brother and sisters, whowere now in their 70s and 80s, still working hard all year round, just aswhen I had first met them 45 years previously. Since that