Lessons from Lost Worlds

By Jared Diamond

Children have a wonderful ability to focus their parents' attention on the essentials. Before our twin sons were born in 1987, I had often heard about all the environmental problems projected to come to a head toward the middle of this century. But I was born in 1937, so I would surely be dead before 2050. Hence I couldn't think of 2050 as a real date, and I couldn't grasp that the environmental risks were real.

After the birth of our kids, my wife and I proceeded to obsess about the things most parents obsess about--schools, our wills, life insurance. Then I realized with a jolt: my kids will reach my present age of 65 in 2052. That's a real date, not an unimaginable one! My kids' lives will depend on the state of the world in 2052, not just on our decisions about life insurance and schools.

I should have known that. Having lived in Europe for years, I saw that the lives of my friends also born in 1937 had been affected greatly by the state of the world around them. For many of those overseas contemporaries growing up during World War II, that state of the world left them orphaned or homeless. Their parents may have thought wisely about life insurance, but their parents' generation had not thought wisely about world conditions. Over the heads of our own children now hang other threats from world conditions, different from the threats of 1939-45.

While the risk of nuclear war between major powers still exists, it's less acute now than 15 years ago, thank God. Many people worry about terrorists, and so do I, but then I reflect that terrorists could at worst kill "only" a few tens of millions of us. The even graver environmental problems that could do in all our children are environmental ones, such as global warming and land and water degradation.

These threats interact with terrorism by breeding the desperation that drives some individuals to become terrorists and others to support terrorists. Sept. 11 made us realize that we are not immune from the environmental problems of any country, no matter how remote--not even those of Somalia and Afghanistan. Of course, in reality, that was true before Sept. 11, but we didn't think much about it then. We and the Somalis breathe and pollute the same atmosphere, are bathed by the same oceans and compete for the same global pie of shrinking resources. Before Sept. 11, though, we thought of globalization as mainly meaning "us" sending "them" good things, like the Internet and Coca-Cola. Now we understand that globalization also means "them" being in a position to send "us" bad things, like terrorist attacks, emerging diseases, illegal immigrants and situations requiring the dispatch of U.S. troops.

A historical perspective can help us, because ours is not the first society to face environmental challenges. Many past societies collapsed partly from their failure to solve problems similar to those we face today--especially problems of deforestation, water management, topsoil loss and climate change. The long list of victims includes the Anasazi in the U.S. Southwest, the Maya, Easter Islanders, the Greenland Norse, Mycenaean Greeks and inhabitants of the Fertile Crescent, the Indus Valley, Great Zimbabwe and Angkor Wat. The outcomes ranged from "just" a collapse of society, to the deaths of most people, to (in some cases) everyone's ending up dead. What can we learn from these events? I see four main sets of lessons.

First, environmental problems can indeed cause societies to collapse, even societies assaulting their environments with stone tools and far lower population densities than we have today.

Second, some environments are more fragile than others, making some societies more prone to collapse than others. Fragility varies even within the same country: for instance, some parts of the U.S., including Southern California, where I live, are especially at risk from low rainfall and salinization of soil from agriculture that is dependent on irrigation--the same problems that overwhelmed the Anasazi. Some nations occupy more fragile environments than do others. It's no accident that a list of the world's most environmentally devastated and/or overpopulated countries resembles a list of the world's current political tinderboxes. Both lists include Afghanistan, Haiti, Iraq, Nepal, Rwanda and Somalia.

Third, otherwise robust societies can be dragged down by the environmental problems of their trade partners. About 500 years ago, two Polynesian societies, on Henderson Island and Pitcairn Island, vanished because they depended for vital imports on the Polynesian society of Mangareva Island, which collapsed from deforestation. We Americans can well understand that outcome, having seen how vulnerable we are to instability in oil-exporting countries of the Middle East.

Fourth, we wonder, Why didn't those peoples see the problems developing around them and do something to avoid disaster? (Future generations may ask that question about us.) One explanation is the conflicts between the short-term interests of those in power and the long-term interests of everybody: chiefs were becoming rich from processes that ultimately undermined society. That too is an acute issue today, as wealthy Americans do things that enrich themselves in the short run and harm everyone in the long run. As the Anasazi chiefs found, they could get away with those policies for a while, but ultimately they bought themselves the privilege of being merely the last to starve.

Of course, there are differences between our situation and those of past societies. Our problems are more dangerous than those of the Anasazi. Today there are far more humans alive, packing far greater destructive power, than ever before. Unlike the Anasazi, a society today can't collapse without affecting societies far away. Because of globalization, the risk we face today is of a worldwide collapse, not just a local tragedy.

People often ask if I am an optimist or a pessimist about our future. I answer that I'm cautiously optimistic. We face big problems that will do us in if we don't solve them. But we are capable of solving them. The risk we face isn't that of an asteroid collision beyond our ability to avoid. Instead our problems are of our own making, and so we can stop making them. The only thing lacking is the necessary political will.

The other reason for my optimism is the big advantage we enjoy over the Anasazi and other past societies: the power of the media. When the Anasazi were collapsing in the U.S. Southwest, they had no idea that Easter Island was also on a downward spiral thousands of miles away, or that Mycenaean Greece had collapsed 2,400 years earlier. But we know from the media what is happening all around the world, and we know from archaeologists what happened in the past. We can learn from that understanding of remote places and times; the Anasazi didn't have that option. Knowing history, we are not doomed to repeat it.

Jared Diamond is a UCLA professor of geography and public health, a director of the World Wildlife Fund and author of the Pulitzer-prizewinning book Guns, Germs, and Steel: The Fates of Human Societies