How plesiosaurs swam underwater - Science Daily

Plesiosaurs are characterized by four uniform flippers. It was possible to reconstruct whether they used these in a rowing or flying motion underwater thanks to a combination of paleontological and engineering methods.

Plesiosaurs, which lived about 210 million years ago, adapted to life underwater in a unique way: their front and hind legs evolved in the course of evolution to form four uniform, wing-like flippers… [+6142 chars]

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