Collapse: How Societies Choose to Fail or Succeed

by Jared Diamond

It was formerly believed that Maya farming was based on slash-and-burn agriculture (so-called swidden agriculture) in which forest is cleared and burned, crops are grown in the resulting field for a year or a few years until the soil is exhausted, and then the field is abandoned for a long fallow period of 15 or 20 years until regrowth of wild vegetation restores fertility to the soil.

We are accustomed to thinking of military success as determined by quality of weaponry, rather than by food supply.

That is, there was a tacitly understood quid pro quo: the reason why the peasants supported the luxurious lifestyle of the king and his court, fed him corn and venison, and built his palaces was because he had made implicit big promises to the peasants. As we shall see, kings got into trouble with their peasants if a drought came, because that was tantamount to the breaking of a royal promise.

Captives were tortured in unpleasant ways depicted clearly on the monuments and murals (such as yanking fingers out of sockets, pulling out teeth, cutting off the lower jaw, trimming off the lips and fingertips, pulling out the fingernails, and driving a pin through the lips), culminating (sometimes several years later) in the sacrifice of the captive in other equally unpleasant ways (such as tying the captive up into a ball by binding the arms and legs together, then rolling the balled-up captive down the steep stone staircase of a temple).

As the archaeologist David Webster succinctly puts it, “Too many farmers grew too many crops on too much of the landscape.”

Because of that requirement, plus the low iron content of bog iron, Viking iron extraction and tool production and even the repair of iron tools consumed enormous quantities of wood, which became a limiting factor in the history of Viking Greenland, where trees were in short supply.

Decisive events in Christianity’s establishment in Scandinavia were the “official” conversion of Denmark under its king Harold Bluetooth around A.D. 960, of Norway beginning around A.D. 995, and of Sweden during the following century.

In short, the explanation of why Iceland became the European country with the most serious ecological damage is not that cautious Norwegian and British immigrants suddenly threw caution to the winds when they landed in Iceland, but that they found themselves in an apparently lush but actually fragile environment for which their Norwegian and British experience had failed to prepare them.

The warmer the temperature at which snow forms, the higher is the proportion of oxygen-18 in the snow’s oxygen. Hence each year’s summer snow is higher in its proportion of oxygen-18 than the same year’s winter snow. For the same reason, snow oxygen-18 in a given month of a warm year is higher than in the same month of a cold year.

and dwarf trees prevalent in poor Greenland pastures. Thus, while the Norse arrived in Greenland with a preference for cows over sheep over goats, the suitability of those animals under Greenland conditions was in the opposite sequence.

As we shall see, that made the Norse vulnerable to starvation from a failure of the seal migration, or from any obstacle (such as ice in the fjords and along the coast, or else hostile Inuit) that impeded their access to the migratory seals.

Just as Australia, when I began visiting it in the 1960s, was more British than Britain itself, Europe’s most remote outpost of Greenland remained emotionally tied to Europe.

However, for Vikings whose self-image focused on terrifying opponents by swinging a mighty battleaxe, to be reduced to making that weapon out of whalebone must have been the ultimate humiliation.

They consist of the five sets of factors that we have already discussed in detail: Norse impact on the environment, climate change, decline in friendly contact with Norway, increase in hostile contact with the Inuit, and the conservative outlook of the Norse.

the values to which people cling most stubbornly under inappropriate conditions are those values that were previously the source of their greatest triumphs over adversity.

Legume food crops that fix atmospheric nitrogen, such as beans, were rotated with other crops—in effect, an independent New Guinean invention of a crop rotation principle now widespread in First World agriculture for maintaining soil nitrogen levels.

‘Friend, is there any land where the sound of the sea is not heard?’ Their confinement has another less obvious result. For all kinds of spatial reference they use the expressions inland and to seawards. Thus an axe lying on the floor of a house is localized in this way, and I have even heard a man direct the attention of another in saying: ‘There is a spot of mud on your seaward cheek.’ Day by day, month after month, nothing breaks the level line of a clear horizon, and there is no faint haze to tell of the existence of any other land.”

On Tikopia, however, people are explicit in saying that their motive for contraception and other regulatory behaviors is to prevent the island from becoming overpopulated, and to prevent the family from having more children than the family’s land could support. For instance, Tikopia chiefs each year carry out a ritual in which they preach an ideal of Zero Population Growth for the island, unaware that an organization founded with that name (but subsequently renamed) and devoted to that goal has also arisen in the First World. Tikopia parents feel that it is wrong for them to continue to give birth to children of their own once their eldest son has reached marriageable age, or to have more children than a number variously given as four children, or one boy and a girl, or one boy and one or two girls.

Another method was abortion, induced by pressing on the belly, or placing hot stones on the belly, of a pregnant woman near term. Alternatively, infanticide was carried out by burying alive, smothering, or turning a newborn infant on its face.

According to Tikopians’ accounts, their ancestors had made that decision because pigs raided and rooted up gardens, competed with humans for food, were an inefficient means to feed humans (it takes about 10 pounds of vegetables edible to humans to produce just one pound of pork), and had become a luxury food for the chiefs.

Thus, part of the Tokugawa solution for the problem of resource depletion in Japan itself was to conserve Japanese resources by causing resource depletion elsewhere, just as part of the solution of Japan and other First World countries to problems of resource depletion today is to cause resource depletion elsewhere.

As in the case of Tikopians and of the Tokugawa Japanese, members of the specialized Indian castes know that they can count on only a circumscribed resource base to maintain themselves, but they expect to pass those resources on to their children. Those conditions have fostered the acceptance of very detailed societal norms by which members of a given caste ensure that they are exploiting their resources sustainably.

Instead, he was merely observing that environmental problems often do create conflicts among people, that conflicts in the U.S. often become resolved in court, that the courts provide a perfectly acceptable means of dispute resolution, and hence that students preparing themselves for a career of resolving environmental problems need to become familiar with the judicial system.

In the 1930s the Belgians required everybody to start carrying an identity card classifying themselves as Hutu or Tutsi, thereby markedly increasing the ethnic distinction that had already existed.

While the killings were organized by the extremist Hutu government and largely carried out by Hutu civilians, institutions and outsiders from whom one might have expected better behavior played an important permissive role. In particular, numerous leaders of Rwanda’s Catholic Church either failed to protect Tutsi or else actively assembled them and turned them over to killers.

But the United Kingdom and Holland have highly efficient mechanized agriculture, such that only a few percent of the population working as farmers can produce much of the food for everyone else, plus some surplus food for export. Rwandan agriculture is much less efficient and unmechanized; farmers depend on handheld hoes, picks, and machetes; and most people have to remain farmers, producing little or no surplus that could support others.

Thus, as André and Platteau note, “The 1994 events provided a unique opportunity to settle scores, or to reshuffle land properties, even among Hutu villagers… It is not rare, even today, to hear Rwandans argue that a war is necessary to wipe out an excess of population and to bring numbers into line with the available land resources.”

Similarly, there are people who have chosen to devote their lives or careers to understanding the origins of the Nazi Holocaust, or to understanding the minds of serial murderers and rapists. They have made that choice not in order to mitigate the responsibility of Hitler, serial murderers, and rapists, but because they want to know how those awful things came to be, and how we can best prevent recurrences.

In Haiti and the Dominican Republic just as elsewhere in the world, the consequences of all that deforestation include loss of timber and other forest building materials, soil erosion, loss of soil fertility, sediment loads in the rivers, loss of watershed protection and hence of potential hydroelectric power, and decreased rainfall.

He constantly maintained a delicate balancing act between the military, the masses, and competing scheming groups of elites; he succeeded in forestalling military coups against him by fragmenting the military into competing groups; and he was able to inspire such fear even in military officers abusing forests and national parks that, in the sequel to a famous unplanned confrontation recorded on television in 1994, I was told that an army colonel who had opposed Balaguer’s forest protection measures and whom Balaguer angrily summoned ended up urinating in his trousers in terror.

The long list ranges from air pollution, biodiversity losses, cropland losses, desertification, disappearing wetlands, grassland degradation, and increasing scale and frequency of human-induced natural disasters, to invasive species, overgrazing, river flow cessation, salinization, soil erosion, trash accumulation, and water pollution and shortages.

Chinese Problems

Foreign aid between 1981 and 2000 included $100 million from international NGOs, a large sum as measured by NGO budgets but a paltry amount compared to China’s other sources: half a billion dollars from the United Nations Development program, $10 billion from Japan’s International Development Agency, $11 billion from the Asian Development Bank, and $24 billion from the World Bank.

In effect, this means that China, like Japan, will be conserving its own forests, but only by exporting deforestation to other countries, several of which (including Malaysia, Papua New Guinea, and Australia) have already reached or are on the road to catastrophic deforestation.

That’s because Australian soils are mostly so old that they have become leached of their nutrients by rain over the course of billions of years.

Such expensive measures led Australians several decades ago to place great hopes in introducing a rabbit disease called myxomatosis, which initially did reduce the population by over 90% until rabbits became resistant and rebounded. Current efforts to control rabbits are using another microbe called the calicivirus.

Unfortunately, closer studies showed that Orange Roughy are very slow-growing, they do not start to breed until they are about 40 years old, and the fish caught and eaten are often 100 years old. Hence Orange Roughy populations cannot possibly breed fast enough to replace the adults being removed by fishermen, and that fishery is now in decline.

Cane Toads, introduced in 1935 to control two insect pests of sugarcane, failed to do that but did spread over an area of 100,000 square miles, assisted by the fact that they can live for up to 20 years and that females annually lay 30,000 eggs. The toads are poisonous, inedible to all native Australian animals, and rate as one of the worst mistakes ever committed in the name of pest control.

To those of us inclined to pessimism or even just to realistic sober thinking, all those facts give us reason to wonder whether Australians are doomed to a declining standard of living in a steadily deteriorating environment. That is an entirely realistic scenario for Australia’s future—much more likely than either a plunge into an Easter Island–like population crash and political collapse as prophesized by doomsday advocates, or a continuation of current consumption rates and population growth as blithely assumed by many of Australia’s current politicians and business leaders. The implausibility of the latter two scenarios, and the realistic prospects of the first scenario, apply to the rest of the First World as well, with the sole difference that Australia could end up in the first scenario sooner.

It is painfully difficult to decide whether to abandon some of one’s core values when they seem to be becoming incompatible with survival. At what point do we as individuals prefer to die than to compromise and live? Millions of people in modern times have indeed faced the decision whether, to save their own life, they would be willing to betray friends or relatives, acquiesce in a vile dictatorship, live as virtual slaves, or flee their country. Nations and societies sometimes have to make similar decisions collectively.

Poor fishermen in tropical reef areas use dynamite and cyanide to kill coral reef fish (and incidentally to kill the reefs as well) in order to feed their children today, in the full knowledge that they are thereby destroying their future livelihood.

Environmentalists blame businesses for harming people by damaging the environment, and routinely putting the business’s financial interests above the public good. Yes, those accusations are often true. Conversely, businesses blame environmentalists for routinely being ignorant of and uninterested in business realities, ignoring the desires of local people and host governments for jobs and development, placing the welfare of birds above that of people, and failing to praise businesses when they do practice good environmental policies. Yes, those accusations too are often true.

That is, cleaning up pollution is usually far more expensive than preventing pollution, just as doctors usually find it far more expensive and less effective to try to cure already sick patients than to prevent diseases in the first place by cheap, simple public health measures.

When the labeled plywood cost 2% more than the unlabeled plywood, of course most customers preferred the cheaper product, but nevertheless a large minority (37%) still proceeded to buy the labeled product. Thus, much of the public really does weigh environmental values in its purchasing decisions, and a significant fraction of the public is willing to pay more for those values.

The criteria that the MSC applies to fisheries were developed in consultation between fishermen, fisheries managers, seafood processors, retailers, fishery scientists, and environmental groups. The principal criteria are that the fishery should maintain its fish stock’s health (including the stock’s sex and age distribution and genetic diversity) for the indefinite future, should yield a sustainable harvest, should maintain ecosystem integrity, should minimize impacts on marine habitats and on non-targeted species (the by-catch), should have rules and procedures for managing stocks and minimizing impacts, and should comply with prevailing laws.

Most knowledgeable scientists now agree that, despite year-to-year ups and downs of temperature that necessitate complicated analyses to extract warming trends, the atmosphere really has been undergoing an unusually rapid rise in temperature recently, and that human activities are the or a major cause. The remaining uncertainties mainly concern the future expected magnitude of the effect: e.g., whether average global temperatures will increase by “just” 1.5 degrees Centigrade or by 5 degrees Centigrade over the next century.

People in the Third World aspire to First World living standards. They develop that aspiration through watching television, seeing advertisements for First World consumer products sold in their countries, and observing First World visitors to their countries. Even in the most remote villages and refugee camps today, people know about the outside world. Third World citizens are encouraged in that aspiration by First World and United Nations development agencies, which hold out to them the prospect of achieving their dream if they will only adopt the right policies, like balancing their national budgets, investing in education and infrastructure, and so on.

What will happen when it finally dawns on all those people in the Third World that current First World standards are unreachable for them, and that the First World refuses to abandon those standards for itself?

The only question is whether they will become resolved in pleasant ways of our own choice, or in unpleasant ways not of our choice, such as warfare, genocide, starvation, disease epidemics, and collapses of societies.

For instance, the value of “one statistical life” in the U.S.—i.e., the cost to the U.S. economy resulting from the death of an average American whom society has gone to the expense of rearing and educating but who dies before a lifetime of contributing to the national economy—is usually estimated at around $5 million.

Today we have over 6 billion people equipped with heavy metal machinery such as bulldozers and nuclear power, whereas the Easter Islanders had at most a few tens of thousands of people with stone chisels and human muscle power. Yet the Easter Islanders still managed to devastate their environment and bring their society to the point of collapse. That difference greatly increases, rather than decreases, the risks for us today.