Pecking order: toothless dinosaur points way to evolution of the beak

Limusaurus fossils found in China suggest they started life eating insects before turning to plants

A small dinosaur that scampered across north-western China 160m years ago boasted a trait not seen in any other dinosaur or other prehistoric creature: it was born with teeth but became toothless by adulthood.

Scientists said fossils of 19 individuals of a dinosaur called Limusaurus, ranging in age from under a year to 10 years, showed that juveniles had small, sharp teeth but adults developed a toothless beak.