![]() ![]() ![]() The sixth wave isn't new it started about twelve thousand years ago when humans began clearing land to plant food crops. Humans now use up more than half of the world's fresh water and nearly half of everything that's grown on land. For the first time, a single species, Homo sapiens-humankind-is wiping out thousands of life forms by consuming and altering the earth's resources. In other words, we've been through this before.īut the sixth wave, the one that's happening now, is different. The fifth and most recent wave, which took place a mere 65 million years ago, destroyed the dinosaurs along with about two-thirds of all animal species alive at that time. And there have already been at least five big waves of mass extinction, caused by everything from meteorites to drought. After all, according to scientists, 99 percent of all species that have ever lived are now extinct. Some might argue that this doesn't seem so tragic. Or, as ornithologist William Beebe put it, "When the last individual of a race of living things breathes no more, another heaven and another earth must pass before such a one can be again." Extinction means that all the members of an entire species are dead that an entire genetic family is gone, forever. To become extinct is the greatest tragedy in nature. By Hoose, Phillip Farrar, Straus and Giroux (BYR) Copyright ©2004 Hoose, Phillip ![]()
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