


The Orkney, Shetland, and Faeroe Island settlements, along with a larger colony on Iceland, misunderstood and misused the forests and soils of those places but learned how to survive, and their descendants live there today.

The Vikings established several colonies in the North Atlantic all suffered environmental degradation, some disastrously. The Mayan civilization, undermined by deforestation, over-farming, a change in rainfall patterns, and wasteful warfare, collapsed suddenly, and the population shrank to a small fraction of its former millions.

Major societies can suffer environmental catastrophes as well. A combination of overpopulation, ecological burdens, and a shift in weather patterns combined disastrously for the Anasazi of the American Southwest. Further west, Pitcairn, Henderson, and Mangareva Islands became so degraded that their residents suffered a failure of trade, the collapse of their ecosystems, and total extinction on Pitcairn and Henderson. In the South Pacific, the Easter Island society, obsessed with competitive monument-building, cut down all its trees, causing a catastrophe and the disappearance of that civilization. Part 2, “Past Societies,” examines several ancient cultures that, stressed by ecological abuse, failed utterly, along with a handful of societies that recovered from environmental dislocations. Part 1, “Modern Montana,” consists of a single chapter that examines a relatively pristine region in present-day America and takes its pulse for signs of environmental danger. These examples can teach the modern world, which suffers from some of the worst environmental degradation in history, how to navigate similar difficulties, restore the regional ecosystems, and escape the deadly fate of their ancestors. Societies often reached their greatest heights just before ecological catastrophe, causing mass starvation and collapse. Through detailed examples, Diamond shows how some civilizations, misunderstanding or ignoring the environmental warnings all around them, suffered catastrophic failure, while other peoples, similarly stressed, made wiser decisions and survived. Especially destructive is deforestation, which causes soil erosion, flooding, loss of wood products, and crop failures. Collapse discusses five major causes for the failure of cultures with degraded environments: human ecological impacts, changes in climate, hostile neighbors, friendly neighbors who back away, and a society’s unwillingness to adapt to changing circumstances.
