Earlier this month DISCOVER covered the 213-million-year-old fossils of the theropod Tawa hallae, a dinosaur ancestor that could show how early dinos spread around the world. Now, in a study (in press) in the Proceedings of the National Academy of Sciences, another research team has uncovered a surprise in the bones of a theropod from almost 100 million years later. By that time, these creatures may have adopted a clever new weapon: venom. Sinornithosaurus lived 125 million years ago in what's now China, and while it might have been covered in feathers (and the size of a turkey), the researchers say it attacked like modern rear-fanged snakes.