How dinosaurs evolved beaks and became birds

Sign up for our free Health Check email to receive exclusive analysis on the week in health Get our free Health Check email Get our free Health Check email SIGN UP I would like to be emailed about offers, events and updates from The Independent. Developmental experiments in the 1980s showed that modern birds could probably generate teeth if their jaw tissue was artificially stimulated with the right molecules. open image in gallery Caenagnathasia jawbone To find out exactly how beaks came to replace dinosaur teeth, the researchers had to look inside the animals’ jaw bones. Wang and colleagues observed that the theropod dinosaur Limusaurus, which was closely related to birds’ ancestors, and the early bird Sapeornis had teeth right to the front of the jaws when they were young but lost them as they grew up. Using the fossils to show how the animals evolved over time suggests beaks in some dinosaurs and bird relatives originally expanded backwards as the animals grew up and tooth sockets closed off.