Sinornithosaurus - Facts and Figures

Sinornithosaurus - Facts and Figures Name: Sinornithosaurus (Greek for Chinese bird-lizard); pronounced sine-OR-nith-oh-SORE-us Habitat: Woodlands of Asia Historical Period: Early Cretaceous (130-125 million years ago) Size and Weight: About three feet long and 5-10 pounds Diet: Probably omnivorous Distinguishing Characteristics: Small size; bipedal posture;  long tail; feathers About Sinornithosaurus   Of all the dino-bird fossils discovered in the Liaoning Quarry in China, Sinornithosaurus may be the most famous, because its the most complete:  the perfectly preserved skeleton of this early Cretaceous dinosaur shows evidence not only of feathers, but of different kinds of feathers on different parts of its body. The feathers on this small theropods head were short and hairlike, but the feathers on its arms and tail were long and distinctively birdlike, with tufts of intermediate length along its back. Technically, Sinornithosaurus is classified as a raptor, on the basis of the single, oversized, sickle-shaped single claws on each of its hind feet, which it used to  tear  at and disembowel prey; on the whole, though, it bears a greater resemblance to the other dino-birds of the Mesozoic Era (like Archaeopteryx and Incisivosaurus) than it does to famous raptors like Deinonychus​ and Velociraptor. At the end of 2009, a team of paleontologists generated headlines by claiming Sinornithosaurus  to be  the first identified venomous dinosaur (never mind that poison-spitting Dilophosaurus you saw in Jurassic Park, which was based on fantasy rather than fact). The supposed evidence in favor of this behavior: fossilized pouches connected by ducts to this dinosaurs snake-like fangs. At the time, reasoning by analogy with modern animals, it would have been surprising if these sacs werent exactly what they appeared to berepositories of venom that Sinornithosaurus used to immobilize (or kill) its prey.  However, a more recent, and more convincing, study has concluded that the supposed  pouches of Sinornithosaurus were created when this individuals incisors loosened from their sockets, and arent evidence of a venomous lifestyle after all!