German dino find clouds picture of feather evolution
[CBC 2006-03-15]

[Photo] Fossilized specimen of Juravenator. (G. Janssen)

The well-preserved fossil of a dinosaur found in southern Germany is complicating the debate about how and when the beasts first evolved feathers.

The 150 million-year-old dinosaur was a meat-eater measuring about 75 centimetres long. Only two other specimens dating to the late Jurassic have been found in Europe.

It belongs to the group of first-known feathered dinosaurs, but a small patch of skin on its tail shows only scaly skin.

Paleontologists are interested in studying feathered dinosaurs to test the view that modern birds descended from dinosaurs.

Ursula Goehlich of the University of Munich and Luis Chiappe of the Dinosaur Institute in Los Angeles named it Juravenator starki after where it was found: the Stark family's limestone quarry in the Jura mountains.

The find suggests the evolution of feathers is more complicated than thought, with some types of dinosaurs becoming feathered later than others, the pair write in Thursday's issue of the journal Nature.

The specimen is only missing the final third of its tail, the study's authors said.

Chinese paleontologist Xu Xing proposed another idea in a journal commentary, noting the specimen was a juvenile that may not yet have developed feathery structures.

Other possibilities are Juraventor's branch of the dinosaur family tree lost its feathers, or the specimen's feathers may simply have failed to fossilize.