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1 .This is Scientific American 60-Second Science. I'm Sophie Bushwick. Got a minute?
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2 .Starting about 12,000 years ago, many species of North American animals began to die out.
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3 .The episode is called the late Pleistocene extinction.
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4 .And it killed off four of the six kinds of American big cats.
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5 .Only cougars and jaguars survived.
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6 .Now researchers say the other felines' diets may have been their doom.
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7 .The clues are found on fossil teeth.
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8 .Gnawing on brittle bones, for example, leaves different marks than chewing tender meat.
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9 .So researchers compared the teeth of cougars to those of American lions and saber-toothed cats that did not make it.
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10 .For context, they also analyzed the marks on the teeth of modern carnivores with known diets, including cougars, lions and hyenas.
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11 .The study is in the journal Biology Letters.
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12 .During tough times, both ancient and modern cougars consumed almost all of their prey, including the bones.
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13 .But the cats that went extinct stayed picky, eschewing rather than chewing some body parts even when food was scarce.
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14 .So next time you're faced with finicky eaters, tell them why there are no more saber-toothed cats.
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15 .Thanks for the minute, for Scientific American 60-Second Science. I'm Sophie Bushwick.
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