In a first, scientists have discovered fossilized blubber dating to the Jurassic Period. It suggests ichthyosaurs, a marine reptile that lived 180 million years ago, were actually warm-blooded.

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In a first, scientists have discovered fossilized blubber dating to the Jurassic Period. It suggests ichthyosaurs, a marine reptile that lived 180 million years ago, were actually warm-blooded.