While the small dinosaur Ornitholestes is long since extinct, her basic biology was solid enough in her close genetic cousins, for instance, to adapt to flight or even lose their teeth completely in favor of a beak. It it is not difficult to imagine, when looking at a modern Cassowary for example, to really get an idea of just how these small theropods looked or even moved around and behaved during the Jurassic Period. Feathers as a flock of fur (a type of scale actually) would have come around first to provide warmth and dryness....and would then further be adapted for flight. Close examination of fossil evidence now confirms that virtually ALL theropod dinosaurs were covered in some form of insulating feather/fur. The Triassic, Jurassic and Cretaceous Periods were a large chunk of the Earth's history and had plenty of cold and wet climates, feathers would have been nearly tantamount to long term survival.
Having chicken for dinner tonight? Well, you're eating a dinosaur.
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