Were the dinosaurs covered by feathers or scales? Scientists disagree.

Were the dinosaurs covered by feathers or scales? Two scientists find that most had scales.

Palaeontologists Paul Barrett of the Natural History Museum in London and David Evans of the Royal Ontario Museum in Toronto created a database of all known impressions of dinosaur skin tissues. They then identified those that had feathers or feather-like structures, and considered relationships in the dinosaurian family tree.

The results, which Barrett revealed at the Society of Vertebrate Palaeontology’s annual meeting in Los Angeles in late October, indicate that although some ornithischians, such as Psittacosaurus and Tianyulong, had quills or filaments in their skin, the overwhelming majority had scales or armour. Among sauropods, scales were also the norm.

The uncertainty of science: Don’t bet any money on this result. The number of dinosaur fossils actually known is relatively tiny — making the overall database tiny as well — and further discoveries could change everything.