Researchers have uncovered the fossil of an early mammal named the “crazy beast” that lived 66 million years ago on Madagascar, and it’s unlike any mammal ever known, living or extinct. This mammal, about the size of an opossum, had a mix of strange characteristics.
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For instance, Adalatherium had more holes on its face than any known mammal, [said researcher David Krause]. These holes, called foramina, created pathways for blood vessels and nerves, leading to an incredibly sensitive snout that was covered in whiskers. It also had a large hole at the top of the snout that can’t be compared to any known mammal that ever lived or is currently living.
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The animal’s backbone contained more vertebrae than any known mammal from the Mesozoic era. And it must have walked in a strange way, because the front half of the animal doesn’t match the back half.
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The researchers chalk it up to evolving in the isolated environment of an island. And Madagascar has been an island for a long time. It separated from the Indian subcontinent 88 million years ago and has been on its own ever since.
This allowed animals and dinosaurs on Madagascar, like Adalatherium “ample time to develop its many ludicrous features,” Krause said.