Palaeontology: 'modern' feathers on a non-avian dinosaur.

Abstract

Discoveries of integumentary coverings on non-avian theropod dinosaurs are becoming commonplace. But the only definitive evidence so far that any of these animals had feathers as we know them today has come from the oviraptorosaur Caudipteryx and the enigmatic coleurosaur Protarchaeopteryx, both of which are considered by some to be secondarily flightless birds. Here we describe the occurrence of pinnate feathers, which clearly feature a rachis and barbs, on a small, non-avian dromaeosaur from northern China. This finding indicates that feathers of modern aspect evolved in dinosaurs before the emergence of birds and flight.