This is Scientific American 60 second Science, I’m Sophie Bushwick. Got a minute?

It was thought that (saltwater) seas separated Central and South America millions of years ago. But a recent discovery may (render) that idea all wet. Because archaeologists in Panama have dug up the remains of ancient alligator relatives—which were freshwater (creatures). The work is in the Journal of Vertebrate Paleontology. 英语口语培训

Excavations at the Panama Canal have (turned up) many fossils. Recently, two partial skulls were found embedded in rocks that date back more than 19 million years, which makes them the oldest crocodilian fossils ever found in Central America. The skulls are from two (species) of the freshwater reptiles called caimans. Modern caimans are related to North American alligators but live only in South America.易说堂电话英语

To reach Panama, the caimans must have left South America around the beginning of the Miocene epoch, when ocean separated the two (continents). These freshwater animals should only have been able to cross a short expanse of saltwater. So at the time, Central and South America may have been much closer than we thought. Either that, or those caimans (hitched a ride).

Thanks for the minute for Scientific American 60 second science, I’m Sophie Bushwick.

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