Quick Facts
Name Meaning:	Hollow Form
Distribution:	South Western and Eastern U.S.
Time Period:	Late Triassic, 208-200 Ma
Length:	9 ft (2.8 m)
Weight:	100 lb (45 kg)
Diet:	Fish, small lizards
Linnaean Classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Superorder:	Dinosauria
Order:	Saurischia
Suborder:	Theropoda
Family:	Coelophysidae
Genus:	Coelophysis
Cladistic Classification
Dinosauria Saurischia Theropoda Ceratosauria Coelophysoidea Coelophysidae Coelophysis

History

Coelophysis tooth.

Grallator track made by a dinosaur such as the Coelophysis.

The Coelophysis was first named by Edward Drinker Cope in 1889. However, the specimens then in possession were not very revealing about the species. In 1947 a virtual graveyard was discovered by Edwin Colber and George Whitaker in the Chama River valley, in northern New Mexico. Several dozens specimens were found including many complete skeletons. During the Triassic period, water was scarce due to the elevated hot and dry temperatures meaning that this find was probably a large herd of Coelophysis that had grouped at a drying waterhole in an attempt to obtain water. Before or after death they were probably exposed to a flash flood, which would have buried them. Because of this discovery the Coelophysis has become one of the most well known dinosaurs. In 1998 a Coelophysis skull was sent in the space shuttle, "Endeavor" becoming the first dinosaur in space.

Description

The Coelophysis was a small, lightly built dinosaur, weighing approximately 100 pounds. It receives its name, "Hollow Form," from the hollow nature in its bones and skull, similar to birds, which allowed it to travel with speed. It had a long body, a narrow pointed head, and small pointed teeth. Its arms had three fingers, and the legs each bore three toes. It would have had large eyes for good eyesight. Evidence shows two different types of Coelophysis, robust and gracile, which probably represent male and female. Its long tail was curiously constructed with an interlocking structure of the vertebrae allowing the tail to move only from side to side and preventing vertical movement. This may have helped it while moving at great speeds as a rudder.

Lifestyle

The Coelophysis was a predator, preying on small animals, though they may have hunted larger prey in packs. Although no concrete evidence suggests that they hunted in packs the mass find in New Mexico hints that this was possible. Discovery of baby Coelophysis in the abdominal region of the adult suggests that they may have cannibalized their own young. However, this may have been an adult fossilized on top of a younger dinosaur. No other evidence for cannibalism currently exists.