A 125m-year-old dinosaur species resembling a bird used venom to subdue its prey according to a new theory based on the shape of some of the creature’s teeth. “Sinornithosaurus's upper teeth resemble those of ‘rear-fanged’ snakes which bite their prey and channel venom into the wound. The dinosaur probably fed on the abundant birds which inhabited what is now north-east China. The work appears in Proceedings of the National Academy of Sciences journal. Rear-fanged snakes are considered less dangerous than other venomous snakes. The fangs in these snakes do not inject venom, but instead channel the poison along a groove on the outer surface of teeth that pierce their prey's flesh. Sinornithosaurus had upper teeth that were similarly long, grooved and fang-like. David Burnham, from the University of Kansas, US, and colleagues, say the dinosaur's upper jaw also contained a pocket that could have housed a venom gland.”