A report in Science suggests that, contrary to previous ideas of the evolution of feathered birds from dinosaurs with scales, perhaps even the earliest dinosaurs might have had a mixture of feathers and scales.

The authors of the report (led by Dr Pascal Godefroit of the Royal Belgian Institute of Natural Sciences in Brussels, Belgium) have found an neornithischian dinosaur from Siberia dating from the Jurassic (150 million years ago – mya). The creature, called Kulindadromeus zabaikalicus, was about 1m long, with a short snout, long hind legs, short arms, and five strong fingers.

This new data, when added to evidence of a different evolutionary line (the theropod group) in northeastern China dating from the Middle Jurassic to Early Cretaceous (170 – 150 mya) which had a mixture of scales and feathers, suggests that perhaps even the earliest dinosaurs (from Middle Triassic 250 mya) had feathers.

The discovery adds weight to the theory which has prevailed for years, that the earliest dinosaurs were feathered and warm blooded. Feathers were initially used for insulation and signalling, only later being adapted for flying.