Why did once flourishing societies collapse and disappear? Jared Diamond, the Pulitzer Prize-winning geographer at UCLA, has spent much of his distinguished career wrestling with this profound question. It is not merely a romantic mystery; the answers, he believes, offer us the prospect of self-preservation.

In Collapse: How Societies Choose to Fail or Succeed, a magisterial analysis remarkable for its ambitious sweep and interpretive panache, Diamond studies four ancient societies across space and time  Easter Island in Polynesia, the Native American Anasazi tribe in what is now the Southwestern United States, the Maya civilization in Central America and the Viking settlement on the coast of Greenland. Although diverse in nature and context, these four societies experienced what Diamond calls ecocide, unintentional ecological suicide.

For example, seafaring Polynesians initially settled on forested Easter Island 1,100 years ago. They cut the trees for canoes and firewood, and used logs to help transport huge stone statues weighing as much as 80 tons. Eventually, however, the islanders chopped down all the forests, and their society collapsed in an epidemic of cannibalism. By the year 1600 all of the trees and land birds on Easter Island were extinct. Today the island is barren grassland devoid of trees. The parallels between Easter Island and the whole modern world, Diamond notes, are chillingly obvious.

Diamond, an evolutionary biologist trained in biochemistry and physiology, deftly uses comparative method and multidisciplinary tools  archaeology, anthropology, paleontology, botany and history  to marshal convincing evidence that sustaining successful societies over time depends primarily on the quality of human interaction with the environment.

All of the vanished societies experienced environmental damage such as deforestation, soil erosion, the intrusion of saltwater or over-hunting of game animals. The second common factor was climate change, such as cooling temperatures or increased aridity. People can survive environmental stress as long as the climate is temperate and the rainfall is regular. But the interaction of environmental and climatic strain proves deadly.

Add to that mix hostile neighbors, rapid population growth and a loss of trading partners, Diamond concludes, and few societies can survive for long. What ultimately caused ecocide, however, were flawed human responses to societal crises. In other words, environmental degradation does not ensure collapse. A societys fate very much depends upon how it manages challenging situations.

Diamond reveals, for instance, how the Vikings who settled in Greenland after AD 984 established a Norwegian pastoral economy, raising sheep, goats and cattle. They also hunted caribou and seal, and they developed a flourishing trade sending walrus ivory to Norway. But 300 years later the Vikings vanished from Greenland.

Documentary sources along with physical evidence reveal that the Viking settlements gradually experienced deforestation and soil erosion. Greenland's climate also grew colder in the 14th and 15th centuries. Colder weather impeded commerce with Norway and reduced the production of hay, which in turn diminished the size of herds.

At the same time that the Vikings were being cut off from Norway, the Inuits began attacks on the Norse settlements in Greenland. Cultural prejudices prevented the Vikings from adopting Inuit technologies, such as harpoons, so they could not harvest whales. Nor were they willing to mimic the Inuits in developing dog sleighs and sealskin kayaks and seagoing boats. As a result of their cultural prejudices (what Diamond calls their "bad attitude"), the Vikings by 1440 had all died out in Greenland, whereas the Inuits survive to this day.

Diamonds perspective is not solely historical. He also discusses contemporary developments in Somalia, Rwanda, Haiti, China and Australia, as well as Montana, a state that once was among the wealthiest in the nation and is now struggling with widespread poverty, population decline and profound environmental problems.

This fascinating new book overflows with interest and insight. Diamond complements his sobering analysis of collapsed civilizations with more uplifting examples of societies (New Guinea, Tikopia, Tokugawa Japan, the Dominican Republic) that have found ways to sustain themselves without overexploiting their environments.

What determines a societys fate, Diamond concludes, is the ability of its leaders and citizens to anticipate problems before they become crises, how accurately leaders perceive a crisis when it does occur, and how decisively a society responds to such crises. Such factors seem obvious, yet Diamond marshals overwhelming evidence of the short-sightedness, selfishness and fractiousness of many otherwise robust cultures. He reveals that many leaders were (and are) so absorbed with their own pursuit of power that they lost sight of festering systemic problems.

Today, Diamond observes, the world is on a non-sustainable course, yet he remains a cautious optimist. The problems facing us are stern but not insoluble. They demand stiff political will, a commitment to long-term thinking and a willingness to make painful changes in what we value.

The fact that the United States over the past 30 years has reduced major air pollutants by a quarter at the same time that energy consumption and population have risen 40 percent gives Diamond hope. So does the success of many nations in slowing their rates of population growth. As he concludes, we have the opportunity to learn from the mistakes of distant peoples and past peoples. Will we?

-- David Shi is a historian, writer and president of Furman University