Sidebar: The Sixth Extinction?
Five times in Earth’s history, scientists believe, natural catastrophes wiped out large numbers of species in short periods of time. The most recent extinction, about 65 million years ago, finished off the dinosaurs.
Today, species are again dying off quickly, due primarily to habitat loss and overexploitation by humans. Harvard scientist E.O. Wilson estimated that some 30,000 species perish each year. That’s about three an hour.
“So many animals are severely endangered,” says Reptile Discovery Center curator Jim Murphy, “that some refer to it as the sixth extinction.” He adds, “Some of my herpetological colleagues are now calling themselves ‘extinction biologists’ or ‘forensic taxonomists.’” When asked if he thinks of himself in those terms, Murphy responds, “I’m getting there.”
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