Weird but true- some dinosaurs had feathers. There have been many feathered dinosaurs found in China but none amaze scientists more than the discovery of Sinornithosaurus. Sinornithosaurus proved birds and dinosaurs are closely related. Sinornithosaurus belonged to the Dromaeosaur family. This is the same family that Utahraptor, Deinonychus, Dromaeosaurus, Velociraptor, and other dinosaurs that had the killer claw belonged to. Like Sinornithosaurus, they would have had feathers, too. Even though Sinornithosaurus had feathers, it couldn't fly. Instead, it would have used them to keep its tiny body warm and to attract a mate. Sinornithosaurus may also be the first venomous dinosaur discovered. In the upper jaw of Sinornithosaurus, paleontologists have found what may have been a pocket for a venom gland. This hypothesis is supported by the fact that the dinosaur has long, grooved teeth below this pocket. It may have used this venom to kill prey larger than itself.