Dryosaurus

From Wikipedia, the free encyclopedia

Dryosaurus
Fossil range: Late Jurassic
D. altus skeleton (below) with Ceratosaurus
D. altus skeleton (below) with Ceratosaurus
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Superorder: Dinosauria
Order: Ornithischia
Suborder: Cerapoda
Infraorder: Ornithopoda
Family: Dryosauridae
Genus: Dryosaurus
Marsh, 1878
Species

D. altus
D. lettowvorbecki

Dryosaurus (pronounced /ˌdraɪoʊˈsɔrəs/ DRY-oh-SAWR-us) meaning 'oak lizard', due to the vague oak shape of its cheek teeth (Greek dryo meaning 'oak' and sauros meaning 'lizard') was a genus of an ornithopod dinosaur that lived in the Late Jurassic Period. It was an iguanodont (formerly classified as a hypsilophodont). Fossils have been found in the western United States and Tanzania and were first discovered in the late 19th century. The Tanzanian site proved to be an especially fertile hunting ground for Dryosaurus fossils, this specimen was previously called Dysalotosaurus (meaning "lost wood reptile"). An expedition led by German paleontologist Werner Janensch found a great many fossils that represented Dryosaurus at all stages of development.

Dryosaurus restoration.
Dryosaurus restoration.

Dryosaurus had a long neck, long, slender legs and a long, stiff tail. Its 'arms', however, with five 'fingers' on each 'hand', were short. It was about eight to 14 feet (2.5 to 4.5 m) long, five feet (1.5 m) tall (at the hips) and weighed 170 to 200 pounds (80 to 90 kg). Its eyes were quite large, leading many to believe that it possessed excellent eyesight.

Dryosaurus had a horny beak and cheek teeth and, like other ornithopods, was a herbivore. Some scientists suggest that it stored food in its cheeks. It was probably a herd animal, which raised and protected its young after hatching.

A quick and agile runner with strong legs, Dryosaurus used its tail as a counter-balance. It probably relied on its speed as a main defense against carnivorous dinosaurs.

Its intelligence, as measured by its Encephalization Quotient (brain-to-body ratio), was midway when compared to other dinosaurs.

D. lettowvorbecki skeleton in Berlin
D. lettowvorbecki skeleton in Berlin

[edit] In popular culture

[edit] External links