Are the environmental resources being destroyed? Are the forests, fisheries or water supplies depleted or the soil eroded?
• Climate changes. Are climate changes—warmer, colder, wetter or dryer—making it difficult for people to cope. • Enemies. Are there enemies who will attack the society when it’s weakened by its declining environmental resources? • Friendly neighbors. Does a weakened society have a friendly neighbor or two with whom it can trade and receive essential resources? • A society’s response. When the environmental problems exist, are they recognized and solved? Diamond told the audience that his students at the University of California, Los Angeles, where he teaches geography, often ask him, ‘Why on earth do people do seemingly dumb things? Over hunt. Over fish. Not manage the water supply.’ It seems like a simple question, but it turns out the reasons why societies make fatal mistakes are complicated and interesting.” One reason is that a society may not anticipate a problem, because it is unprecedented. For instance, 30 years ago, no one dreamed of the possibility of global warming. It’s not
