Since the Interchange there have been ground sloths in North America, as well as armadillos (including the enormous glyptodonts). Coming the other way, llamas, alpacas, guanacos and vicuñas, all members of the camel family, are now confined to South America, but camels originally evolved in North America. They spread into Asia and then Arabia and Africa quite recently, presumably via Alaska, where they gave rise to the Bactrian camels of the Mongolian steppe, and the dromedaries of the hot deserts. The horse family, too, did most of their evolving in North America but then went extinct there,
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