Every time mankind has stepped forward, it has left behind a nasty footprint.
Early hunters decimated populations of the woolly mammoth. The ancient Chinese exhausted their soil. The Greek and Roman civilizations turned the forested Mediterranean into a semidesert long before AD 1000 had rolled around.
But it's the latest millennium that has really transformed the earth. Industrialization, unprecedented population growth, and trade have shrunk the wilderness, devastated ecosystems, and now threaten the planet. Many environmentalists believe we've already poked such a hole in the ozone layer and pumped so many greenhouse gases into the atmosphere that global disaster looms.
At the same time, the last 1,000 years reveal humanity's growing awareness of its nature-trashing ways and its ingenuity in minimizing them. Societies have found new methods of production and new methods to limit pollution. Governments have cordoned off vast tracts of land and water either to regulate human exploitation or ban it altogether.
New environmental problems will sorely test that ingenuity. We will either race ahead with new technology or change our ways to live more lightly on earth (or perhaps some combination of the two). Either avenue will reorient our relationship with the natural world.
"We're part of the web of life," says John Cairns, professor emeritus of environmental biology at Virginia Tech in Blacksburg, Va. "If we destroy any part of the web, then we're inflicting self-damage. That's the paradigm shift that's beginning to occur. You have to think of the ecosystem as almost an extension of yourself."
To 11th-century peasants laboring in Europe, such notions would have seemed entirely foreign. Life was rude and agriculture marginal enough that, as a practical matter, nature needed to be beaten back at every turn. Even as a religious idea, nature was no Garden of Eden but, according to the prevailing Christian view, a fallen world.
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