Extinction and the Mammoth Steppe
During the Pleistocene Ice Age that ended 12,000 years ago, many large mammals coexisted in an ecosystem that paleontologist Dale Guthrie dubbed the “mammoth steppe,” an icy prairie too cold, windy, and dry to support more than a few trees. When this ecosystem faded away at the end of the lce Age, many of its characteristic animals, like the mammoth, the wolly rhino, and the short-faced bear, went extinct, while a new set of megafauna—moos,elk, and bison—invaded Alaska and the Yukon. To understand the varied fates of these big herbivores, Guthrie looks to their digestive systems.
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