Juravenator

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iJuravenator

Extinct (fossil)

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Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Sauropsida
Order:	Saurischia
Infraorder:	Coelurosauria
Family:	Compsognathidae
Genus:	Juravenator

Binomial name

Juravenator starki
Göhlich & Chiappe, 2006

Juravenator was a small (2.5 feet long) compsognathid dinosaur, which lived in the area which would someday become the Jura mountains of Germany, 150 million years ago.

It was a close relative of Sinosauropteryx, for which there is fossil evidence of a downy, feather-like covering, yet a patch of fossilized Juravenator skin shows only normal dinosaur scales, with no sign of feathers at all. While it may simply have never had feathers, paleontologist Mark Norell suggest that the presence of scales on the Juravenator tail could mean a number of things [1]:

Juravenator could have lost its feathers secondarily on at least some parts of its body, like some modern, partially featherless birds.
Feathers could have evolved more than once in different types of dinosaur.
Since the only known Juravenator skeleton is juvenile, it could be that this species only grew a significant covering of feathers as they aged, or lost feathers seasonally.
The feathers might simply have not been preserved in this specimen. "Feathers are really just difficult things to preserve," Norell says, though Luis Chiappe, director of the Dinosaur Institute at the Natural History Museum of Los Angeles County points out that the fossil skin does not show the follicles normally associated with dinosaur skin that has lost its feathers.

The fossil, found in 1998 by amateur paleontologist Klaus-Dieter Weiß in a lime pit near Eichstätt, had been nicknamed Borsti in German, a name commonly given to bristle-haired dogs, on the assumption the creature was endowed with bristly protofeathers.