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1 .This is Scientific American 60-Second Science. I'm Sophie Bushwick. Got a minute?
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2 .It was thought that saltwater seas separated Central and South America millions of years ago.
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3 .But a recent discovery may render that idea all wet.
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4 .Because archaeologists in Panama have dug up the remains of ancient alligator relatives,
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5 .which were freshwater creatures.
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6 .The work is in the Journal of Vertebrate Paleontology.
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7 .Excavations at the Panama Canal have turned up many fossils.
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8 .Recently, two partial skulls were found embedded in rocks that date back more than 19 million years,
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9 .which makes them the oldest crocodilian fossils ever found in Central America.
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10 .The skulls are from two species of the freshwater reptiles called caimans.
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11 .Modern caimans are related to North American alligators but live only in South America.
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12 .To reach Panama, the caimans must have left South America around the beginning of the Miocene epoch, when ocean separated the two continents.
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13 .These freshwater animals should only have been able to cross a short expanse of saltwater.
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14 .So at the time, Central and South America may have been much closer than we thought.
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15 .Either that, or those caimans hitched a ride.
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16 .Thanks for the minute, for Scientific American 60-Second Science. I'm Sophie Bushwick.
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