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Table of Contents PENGUIN BOOKS Title Page Copyright Page Dedication Epigraph PART ONE - MODERN MONTANA CHAPTER 1 - Under Montana’s Big Sky PART TWO - PAST

SOCIETIES CHAPTER 2 - Twilight at Easter CHAPTER 3 - The Last People Alive: Pitcairn and Henderson Islands CHAPTER 4 - The Ancient Ones: The Anasazi and Their Neighbors CHAPTER 5 - The Maya Collapses CHAPTER 6 - The Viking Prelude and Fugues CHAPTER 7 - Norse Greenland’s Flowering CHAPTER 8 - Norse Greenland’s End CHAPTER 9 - Opposite Paths to Success PART THREE - MODERN

SOCIETIES CHAPTER 10 - Malthus in Africa: Rwanda’s Genocide CHAPTER 11 - One Island, Two Peoples, Two Histories: The Dominican Republic ... CHAPTER 12 - China, Lurching Giant CHAPTER 13 - “Mining” Australia PART FOUR - PRACTICAL LESSONS CHAPTER 14 - Why Do Some Societies Make Disastrous Decisions? CHAPTER 15 - Big Businesses and the Environment: Different Conditions, ...

CHAPTER 16 - The World as a Polder: What Does It All Mean to Us Today? AFTERWORD Acknowledgements FURTHER READINGS INDEX ILLUSTRATION CREDITS

PENGUIN BOOKS

COLLAPSE Jared Diamond is a professor of geography at the University of California, Los Angeles. He began his scientific career in physiology and expanded into evolutionary biology and biogeography. He has been elected to the National Academy of Arts and Sciences and the American Philosophical Society. Among Dr. Diamond’s many awards are the National Medal of Science, the Tyler Prize for Environmental Achievement, Japan’s Cosmos Prize, a MacArthur Foundation Fellowship, and the Lewis Thomas Prize honoring the Scientist as

Poet, presented by the Rockefeller University. He has published more than two hundred articles in Discover, Natural History, Nature, and Geo magazines. His previous books include The Third Sex and The Third Chimpanzee. His most recent book, Guns, Germs, and Steel, was awarded the Pulitzer Prize.

Chosen as Best Book of the Year by The Washington Post, The Boston Globe,

the Los Angeles Times, the San Francisco Chronicle, The Economiser,

and Discover

Praise for Collapse “Extraordinary in erudition and originality, compelling in [its] ability to relate the digitized pandemonium of the present to the hushed agrarian sunrises of the far past.”

—The New York Times Book Review

“Readers learn on page 1 that they are in for quite a ride. No reader may carp that Diamond has provided a set of examples that is too limited chronologically or geographically. Diamond . . . has been to most of the lands cited, often staying for months or even years, and what he writes about them and their populations is informed and engagingly colored by personal observation. The Icelanders . . . learned to

face up to reality and adapt to living within the limits of their environments. Jared Diamond has written a book to help us do the same.”

—Los Angeles Times

“ W it h Collapse, Jared Diamond has written a fascinating account of the collapse of civilizations around the world.... A reader cannot help but leave the book wondering whether we are following the track of these other civilizations that failed. Any reader of Collapse will leave the book convinced that we must take steps now to save our planet.”

—The Boston Globe

“In a world that celebrates live journalism, we are increasingly in need of big-picture authors like Jared Diamond, who think historically and spacially— across an array of disciplines—to make sense of events that journalists may seem to be covering in depth, but in fact aren’t. . . . Thank heavens there is someone of the stature of Diamond willing to say so.”

—Robert D. Kaplan, The Washington Post

“Diamond looks to the past and present to sound a warning for the future.”

—Newsweek

“Rendering complex history and science into entertaining prose, Diamond reminds us that those who ignore history are bound to repeat it.”

—People (four stars)

“Taken together Guns, Germs, and Steel and Collapse represent one of the most significant projects embarked upon by any intellectual of our generation. They are magnificent books: extraordinary in erudition and originality, compelling in their ability to relate the digitized pandemonium of the present to the hushed agrarian sunrises of the far past. I read both thinking what literature might be like if every author knew so much, wrote so clearly and formed arguments with such care.”

—The New York Times

“Essential reading for anyone who is unafraid to be

disillusioned if it means they can walk into the future with their eyes open.”

—Nature

“On any short list of brilliant minds in the world today, Diamond makes the cut.”

—San Jose Mercury News

“Read this book. It will challenge you and make you think.”

—Scientific American

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First published in the United States of America by Viking

Penguin, a member of Penguin Group (USA) Inc. 2005 Published in Penguin Books 2006 This edition with a new

afterword published 2011

Copyright © Jared Diamond, 2005, 2011 All rights reserved

Maps by Jeffrey L. Ward

Collapse : how societies choose to fail or succeed / Jared

Diamond. p. cm. Includes index. eISBN : 978-1-101-50200-6

1. Social history—Case studies. 2. Social change—Case studies.

3. Environmental policy—Case studies. I. Title. HN13.D5 2005

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To Jack 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 sky

I met a traveler from an antique land Who said: “Two vast and trunkless legs of stone Stand in the desert. Near them, on the sand, Half sunk, a shattered visage lies, whose frown, And wrinkled lip and sneer of cold command, Tell that its sculptor well those passions read, Which yet survive, stampt on these lifeless things, The hand that mockt them and the heart that fed: And on the pedestal these words appear: ‘My name is Ozymandias, 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 sands stretch far away.”

“Ozymandias,” by Percy Bysshe Shelley (1817)

PROLOGUE

A Tale of Two Farms Two farms ■ Collapses, past and

present ■ Vanished Edens? ■ A five- point framework ■ Businesses and the

environment ■ The comparative method ■ Plan of the book ■

A few summers ago I visited two dairy farms, Huls Farm and Gardar Farm, which despite being located thousands of miles apart were still remarkably similar in their strengths and vulnerabilities. Both were by far the

largest, most prosperous, most technologically advanced farms in their respective districts. In particular, each was centered around a magnificent state- of-the-art barn for sheltering and milking cows. Those structures, both neatly divided into opposite-facing rows of cow stalls, dwarfed all other barns in the district. Both farms let their cows graze outdoors in lush pastures during the summer, produced their own hay to harvest in the late summer for feeding the cows through the winter, and increased their production of summer fodder and winter hay by irrigating their fields. The two farms were similar in area (a few square miles) and in barn size, Huls barn holding somewhat more

cows than Gardar barn (200 vs. 165 cows, respectively). The owners of both farms were viewed as leaders of their respective societies. Both owners were deeply religious. Both farms were located in gorgeous natural settings that attract tourists from afar, with backdrops of high snow-capped mountains drained by streams teeming with fish, and sloping down to a famous river (below Huls Farm) or fjord (below Gardar Farm).

Those were the shared strengths of the two farms. As for their shared vulnerabilities, both lay in districts economically marginal for dairying, because their high northern latitudes meant a short summer growing season in

which to produce pasture grass and hay. Because the climate was thus suboptimal even in good years, compared to dairy farms at lower latitudes, both farms were susceptible to being harmed by climate change, with drought or cold being the main concerns in the districts of Huls Farm or Gardar Farm respectively. Both districts lay far from population centers to which they could market their products, so that transportation costs and hazards placed them at a competitive disadvantage compared to more centrally located districts. The economies of both farms were hostage to forces beyond their owners’ control, such as the changing affluence and tastes of their customers

and neighbors. On a larger scale, the economies of the countries in which both farms lay rose and fell with the waxing and waning of threats from distant enemy societies.

The biggest difference between Huls Farm and Gardar Farm is in their current status. Huls Farm, a family enterprise owned by five siblings and their spouses in the Bitterroot Valley of the western U.S. state of Montana, is currently prospering, while Ravalli County in which Huls Farm lies boasts one of the highest population growth rates of any American county. Tim, Trudy, and Dan Huls, who are among Huls Farm’s owners, personally took me on a tour of their high-tech new barn, and patiently

explained to me the attractions and vicissitudes of dairy farming in Montana. It is inconceivable that the United States in general, and Huls Farm in particular, will collapse in the foreseeable future. But Gardar Farm, the former manor farm of the Norse bishop of southwestern Greenland, was abandoned over 500 years ago. Greenland Norse society collapsed completely: its thousands of inhabitants starved to death, were killed in civil unrest or in war against an enemy, or emigrated, until nobody remained alive. While the strongly built stone walls of Gardar barn and nearby Gardar Cathedral are still standing, so that I was able to count the individual cow stalls,

there is no owner to tell me today of Gardar’s former attractions and vicissitudes. Yet when Gardar Farm and Norse Greenland were at their peak, their decline seemed as inconceivable as does the decline of Huls Farm and the U.S. today.

Let me make clear: in drawing these parallels between Huls and Gardar Farms, I am not claiming that Huls Farm and American society are doomed to decline. At present, the truth is quite the opposite: Huls Farm is in the process of expanding, its advanced new technology is being studied for adoption by neighboring farms, and the United States is now the most powerful country in the world. Nor am I claiming that farms or

societies in general are prone to collapse: while some have indeed collapsed like Gardar, others have survived uninterruptedly for thousands of years. Instead, my trips to Huls and Gardar Farms, thousands of miles apart but visited during the same summer, vividly brought home to me the conclusion that even the richest, technologically most advanced societies today face growing environmental and economic problems that should not be underestimated. Many of our problems are broadly similar to those that undermined Gardar Farm and Norse Greenland, and that many other past societies also struggled to solve. Some of those past societies failed (like the

Greenland Norse), and others succeeded (like the Japanese and Tikopians). The past offers us a rich database from which we can learn, in order that we may keep on succeeding. Norse Greenland is just one of many past societies that collapsed or vanished, leaving behind monumental ruins such as those that Shelley imagined in his poem “Ozymandias.” By collapse, I mean a drastic decrease in human population size and/or political/economic/social complexity, over a considerable area, for an extended time. The phenomenon of collapses is thus an extreme form of

several milder types of decline, and it becomes arbitrary to decide how drastic the decline of a society must be before it qualifies to be labeled as a collapse. Some of those milder types of decline include the normal minor rises and falls of fortune, and minor political/ economic/social restructurings, of any individual society; one society’s conquest by a close neighbor, or its decline linked to the neighbor’s rise, without change in the total population size or complexity of the whole region; and the replacement or overthrow of one governing elite by another. By those standards, most people would consider the following past societies to have been famous victims of full-fledged collapses

rather than of just minor declines: the Anasazi and Cahokia within the boundaries of the modern U.S., the Maya cities in Central America, Moche and Tiwanaku societies in South America, Mycenean Greece and Minoan Crete in Europe, Great Zimbabwe 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 romantic fascination for all of us. We marvel at them when as children we first learn of them through pictures. When we grow up, many of us plan vacations in order to experience them at firsthand as tourists. We feel drawn to their often spectacular

and haunting beauty, and also to the mysteries that they pose. The scales of the ruins testify to the former wealth and power of their builders—the boast “Look on my works, ye mighty, and despair!” in Shelley’s words. Yet the builders vanished, abandoning the great structures that they had created at such effort. How could a society that was once so mighty 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 unpleasant way? Lurking behind this romantic mystery is the nagging thought: might such a fate eventually befall our own wealthy society? Will tourists someday 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 abandonments were at least partly triggered by ecological problems: people inadvertently destroying the environmental resources on which their societies depended. This suspicion of unintended ecological suicide—ecocide—has been confirmed by discoveries made in recent decades by archaeologists, climatologists, historians, paleontologists, and palynologists (pollen scientists). The processes through which past societies have undermined themselves by damaging their environments fall into eight categories, whose relative importance differs from case to case: deforestation and habitat destruction,

soil problems (erosion, salinization, and soil fertility losses), water management problems, overhunting, overfishing, effects of introduced species on native species, human population growth, and increased per-capita impact of people.

Those past collapses tended to follow somewhat similar courses constituting variations on a theme. Population growth forced people to adopt intensified means of agricultural production (such as irrigation, double-cropping, or terracing), and to expand farming from the prime lands first chosen onto more marginal land, in order to feed the growing number of hungry mouths. Unsustainable practices led to environmental damage of one or more of

the eight types just listed, resulting in agriculturally marginal lands having to be abandoned again. Consequences for society included food shortages, starvation, wars among too many people fighting for too few resources, and overthrows of governing elites by disillusioned masses. Eventually, population decreased through starvation, war, or disease, and society lost some of the political, economic, and cultural complexity that it had developed at its peak. Writers find it tempting to draw analogies between those trajectories of human societies and the trajectories of individual human lives—to talk of a society’s birth, growth, peak, senescence, and death—and to assume

that the long period of senescence that most of us traverse between our peak years and our deaths also applies to societies. But that metaphor proves erroneous for many past societies (and for the modern Soviet Union): they declined rapidly after reaching peak numbers and power, and those rapid declines must have come as a surprise and shock to their citizens. In the worst cases of complete collapse, everybody in the society emigrated or died. Obviously, though, this grim trajectory is not one that all past societies followed unvaryingly to completion: different societies collapsed to different degrees and in somewhat different ways, 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 some other Third World countries. Many people fear that ecocide has now come to overshadow nuclear war and emerging diseases as a threat to global civilization. The environmental problems facing us today include the same eight that undermined past societies, plus four new ones: human- caused climate change, buildup of toxic chemicals in the environment, energy shortages, and full human utilization of the Earth’s photosynthetic capacity. Most of these 12 threats, it is claimed, will become globally critical within the

next few decades: either we solve the problems by then, or the problems will undermine not just Somalia but also First World societies. Much more likely than a doomsday scenario involving human extinction or an apocalyptic collapse of industrial civilization would be “just” a future of significantly lower living standards, chronically higher risks, and the undermining of what we now consider some of our key values. Such a collapse could assume various forms, such as the worldwide spread of diseases or else of wars, triggered ultimately by scarcity of environmental resources. If this reasoning is correct, then our efforts today will determine the state of the world in which the current

generation of children and young adults lives out their middle and late years.

But the seriousness of these current environmental problems is vigorously debated. Are the risks greatly exaggerated, or conversely are they underestimated? Does it stand to reason that today’s human population of almost seven billion, with our potent modern technology, is causing our environment to crumble globally at a much more rapid rate than a mere few million people with stone and wooden tools already made it crumble locally in the past? Will modern technology solve our problems, or is it creating new 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 substitute some 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 already on course for the world’s population to level off at some manageable number of people?

All of these questions illustrate why those famous collapses of past civilizations have taken on more meaning than just that of a romantic mystery. Perhaps there are some practical lessons that we could learn from all those past collapses. We know that some past societies collapsed while others didn’t: what made certain societies especially vulnerable? What,

exactly, were the processes by which past societies committed ecocide? Why did some past societies fail to see the messes that they were getting into, and that (one would think in retrospect) must have been obvious? Which were the solutions that succeeded in the past? If we could answer these questions, we might be able to identify which societies are now most at risk, and what measures could best help them, 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 naïve as to think that study of the past will yield simple solutions, directly transferable to our

societies today. We differ from past societies in some respects that put us at lower risk than them; some of those respects often mentioned include our powerful technology (i.e., its beneficial effects), globalization, modern medicine, and greater knowledge of past societies and of distant modern societies. We also differ from past societies in some respects that put us at greater risk than them: mentioned in that connection are, again, our potent technology (i.e., its unintended destructive effects), globalization (such that now a collapse even in remote Somalia affects the U.S. and Europe), the dependence of millions (and, soon, billions) of us on modern medicine for our survival, and our much

larger human population. Perhaps we can still learn from the past, but only if we think carefully about its lessons. Efforts to understand past collapses have had to confront one major controversy and four complications. The controversy involves resistance to the idea that past peoples (some of them known to be ancestral to peoples currently alive and vocal) did things that contributed to their own decline. We are much more conscious 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 feel guilty if we demand fresh towels or let

the water run. To damage the environment today is considered morally culpable.

Not surprisingly, Native Hawaiians and Maoris don’t like paleontologists telling them that their ancestors exterminated half of the bird species that had evolved on Hawaii and New Zealand, nor do Native Americans like archaeologists telling them that the Anasazi deforested parts of the southwestern U.S. The supposed discoveries by paleontologists and archaeologists sound to some listeners like just one more racist pretext advanced by whites for dispossessing indigenous peoples. It’s as if scientists were saying, “Your ancestors were bad

stewards of their lands, so they deserved to be dispossessed.” Some American and Australian whites, resentful of government payments and land retribution to Native Americans and Aboriginal Australians, do indeed seize on the discoveries to advance that argument today. Not only indigenous peoples, but also some anthropologists and archaeologists who study them and identify with them, view the recent supposed discoveries as racist lies.

Some of the indigenous peoples and the anthropologists identifying with them go to the opposite extreme. They insist that past indigenous peoples were (and modern ones still are) gentle and ecologically wise stewards of their

environments, intimately knew and respected Nature, innocently lived in a virtual Garden of Eden, and could never have done all those bad things. As a New Guinea hunter once told me, “If one day I succeed in shooting a big pigeon in one direction from our village, I wait a week before hunting pigeons again, and then I go out in the opposite direction from the village.” Only those evil modern First World inhabitants are ignorant of Nature, don’t respect the environment, and destroy it.

In fact, both extreme sides in this controversy—the racists and the believers in a past Eden—are committing the error of viewing past indigenous peoples as fundamentally

different from (whether inferior to or superior to) modern First World peoples. Managing environmental resources sustainably has always been difficult, ever since Homo sapiens developed modern inventiveness, efficiency, and hunting skills by around 50,000 years ago. Beginning with the first human colonization of the Australian continent around 46,000 years ago, and the subsequent prompt extinction of most of Australia’s former giant marsupials and other large animals, every human colonization of a land mass formerly lacking humans—whether of Australia, North America, South America, Madagascar, the Mediterranean islands, or Hawaii and

New Zealand and dozens of other Pacific islands—has been followed by a wave of extinction of large animals that had evolved without fear of humans and were easy to kill, or else succumbed to human-associated habitat changes, introduced pest species, and diseases. Any people can fall into the trap of overexploiting environmental resources, because of ubiquitous problems that we shall consider later in this book: that the resources initially seem inexhaustibly abundant; that signs of their incipient depletion become masked by normal fluctuations in resource levels between years or decades; that it’s difficult to get people to agree on exercising restraint in harvesting a shared resource (the so-

called tragedy of the commons, to be discussed in later chapters); and that the complexity of ecosystems often makes the consequences of some human-caused perturbation virtually impossible to predict even for a professional ecologist. Environmental problems that are hard to manage today were surely even harder to manage in the past. Especially for past non-literate peoples who couldn’t read case studies of societal collapses, ecological damage constituted a tragic, unforeseen, unintended consequence of their best efforts, rather than morally culpable blind or conscious selfishness. The societies that ended up collapsing 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 exterminated or dispossessed, nor all- knowing conscientious environmentalists 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 prone either to succeed or to fail, depending on circumstances similar to those making us prone to succeed or to fail today. Yes, there are differences between the situation we face today and that faced by past peoples, but there are still enough similarities for us to be able to learn

from the past. Above all, it seems to me

wrongheaded and dangerous to invoke historical assumptions about environmental practices of native peoples in order to justify treating them fairly. In many or most cases, historians and archaeologists have been uncovering overwhelming evidence that this assumption (about Eden-like environmentalism) is wrong. By invoking this assumption to justify fair treatment of native peoples, we imply that it would be OK to mistreat them if that assumption could be refuted. In fact, the case against mistreating them isn’t based on any historical assumption about their environmental practices: it’s based

on a moral principle, namely, that it is morally wrong for one people to dispossess, subjugate, or exterminate another people. That’s the controversy about past ecological collapses. As for the complications, of course it’s not true that all societies are doomed to collapse because of environmental damage: in the past some societies did while others didn’t; the real question is why only some societies proved fragile, and what distinguished those that collapsed from those that didn’t. Some societies that I shall discuss, such as the Icelanders and Tikopians, succeeded in solving

extremely difficult environmental problems, have thereby been able to persist for a long time, and are still going strong today. For example, when Norwegian colonists of Iceland first encountered an environment superficially similar to that of Norway but in reality very different, they inadvertently destroyed much of Iceland’s topsoil and most of its forests. Iceland for a long time was Europe’s poorest and most ecologically ravaged country. However, Icelanders eventually learned from experience, adopted rigorous measures of environmental protection, and now enjoy one of the highest per-capita national average incomes in the world. Tikopia Islanders

inhabit a tiny island so far from any neighbors that they were forced to become self-sufficient in almost everything, but they micromanaged their resources and regulated their population size so carefully that their island is still productive after 3,000 years of human occupation. Thus, this book is not an uninterrupted series of depressing stories of failure, but also includes success stories inspiring imitation and optimism.

In addition, I don’t know of any case in which a society’s collapse can be attributed solely to environmental damage: there are always other contributing factors. When I began to plan this book, I didn’t appreciate those

complications, and I naïvely thought that the book would just be about environmental damage. Eventually, I arrived at a five-point framework of possible contributing factors that I now consider in trying to understand any putative environmental collapse. Four of those sets of factors—environmental damage, climate change, hostile neighbors, and friendly trade partners— may or may not prove significant for a particular society. The fifth set of factors —the society’s responses to its environmental problems—always proves significant. Let’s consider these five sets of factors one by one, in a sequence not implying any primacy of cause but just convenience of

presentation. A first set of factors involves damage

that people inadvertently inflict on their environment, as already discussed. The extent and reversibility of that damage depend partly on properties of people (e.g., how many trees they cut down per acre per year), and partly on properties of the environment (e.g., properties determining how many seedlings germinate per acre, and how rapidly saplings grow, per year). Those environmental properties are referred to either as fragility (susceptibility to damage) or as resilience (potential for recovery from damage), and one can talk separately of the fragility or resilience of an area’s forests, its soils, its fish

populations, and so on. Hence the reasons why only certain societies suffered environmental collapses might in principle involve either exceptional imprudence of their people, exceptional fragility of some aspects of their environment, or both.

A next consideration in my five-point framework is climate change, a term that today we tend to associate with global warming caused by humans. In fact, climate may become hotter or colder, wetter or drier, or more or less variable between months or between years, because of changes in natural 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 orientation of the Earth’s axis with respect to its orbit, and changes in the distribution of land and ocean over the face of the Earth. Frequently discussed cases of natural climate change include the advance and retreat of continental ice sheets during the Ice Ages beginning over two million years ago, the so- called Little Ice Age from about A.D. 1400 to 1800, and the global cooling following the enormous volcanic eruption of Indonesia’s Mt. Tambora on April 5, 1815. That eruption injected so much dust into the upper atmosphere that the amount of sunlight reaching the ground decreased until the dust settled