Scientists tend to distrust conclusions that are not based on empirical data and adequate sample sizes. So take what I'm about to say with a large grain of salt, since it is neither empirical nor based on sufficient data. The issue of sustainability is arguably the greatest challenge of our time. How do we provide for 6.7 billion people (rising to over 9 billion by mid-century) without inflicting irreparable harm to our environment? Having recently returned from a trip to Germany, Switzerland, and Sweden, I was struck by the fact that Europe--or at least the small part of it that I saw--seems much closer to addressing this issue than the United States. For example, there was a noticeable absence of sprawl in all three countries. Cites and towns were tightly clustered and surrounded by a larger landscape of farms and forests. Strip malls, shopping centers, and classic suburban housing developments were few and far between; "McMansions" were virtually non-existent. The towns were linked together by reliable, clean trains, while the cities featured safe, efficient, public transportation systems of buses and trolleys. (Indeed, the contrast with Amtrak or New Jersey Transit's overpriced and unreliable trains was glaring). I did not spend much time on the farms, but I was struck by their smaller size and greater diversity of crops compared to their American counterparts. (Of course, one would need to know a lot more about comparative subsidies, market prices, pesticide and fertilizer usage, and other factors before reaching any firm conclusions). No one would argue that Western Europe has actually achieved the elusive goal of sustainability. I doubt, for example, that any of the countries I visited could maintain its current standard of living indefinitely if forced to rely on the natural resources (including farmland) within its borders. And all of these nations are net emitters of greenhouse gases, thereby contributing to global warming. But I do think we in the United States could learn a lot from our European colleagues. They seem to have figured out how to have a high standard of living at significantly less cost to the earth. What do you think? Leave us a comment. ———- David Wilcove is professor of ecology, evolutionary biology, and public affairs at Princeton University and one of the world’s leading experts on endangered species. He is the author of No Way Home: The Decline of the World’s Great Animal Migrations.