fieldmuseumIt’s #FossilFriday! A group of theropod…

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fieldmuseumIt’s #FossilFriday! 
A group of theropod dinosaurs called dromeosaurs are among birds’ closest relatives. Sometimes known as “raptors,” dromaeosaurs were agile predators equipped with a giant “killing claw” on the middle toe. Here, we’re looking at casts of two dromaeosaurs, Buitreraptor gonzalezorum and Deinonychus antirrhopus.
How do we know birds are dinosaurs? They have a defining dino feature: hipbones with openings in the sockets. But that’s not all. When scientists look closely at bird skeletons and dinosaur skeletons, they count more than 100 features in common.