Heterodontosaurus

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Heterodontosaurus
Fossil range: Early Jurassic

Heterodontosaurus tucki

Kingdom:	Animalia
Phylum:	Chordata
Class:	Sauropsida
Superorder:	Dinosauria
Order:	Ornithischia
Family:	Heterodontosauridae
Genus:	Heterodontosaurus Crompton & Charig, 1962

Species

H. tucki Crompton & Charig, 1962 (type)

Heterodontosaurus (meaning "different toothed lizard") is a genus of small herbivorous dinosaur with prominent canine teeth which lived in the Early Jurassic of South Africa. It was similar to a hypsilophodont in shape, and ate plants, despite its canines.

Heterodontosaurus is currently known from specimens of the SAFM (South African Museum) from South Africa. There are two known morphologies of this genus, the second of which is thought by some to represent a different species. The type species, H. tucki, is from the Upper Elliot Formation of the Hettangian age, around 199-196 million years ago.

[edit] Notable anatomical features

Cast of the type specimen of Heterodontosaurus tucki from South Africa, as displayed in the Valley Life Sciences Building of the University of California, Berkeley.

Heterodontosaurus compared in size to a human.

Heterodontosaurus had a long, narrow pelvis and a pubis which resembled those possessed by more advanced ornithischians. More unusual was that the hand of Heterodontosaurus had five fingers, two of which seem to be opposable. This configuration allowed Heterodontosaurus to grasp and manipulate food. Another interesting feature is the specialization of teeth which gave rise to the animal's name. Most dinosaurs (and indeed most reptiles) have a single type of tooth in their jaws, while Heterodontosaurus had three. At the front of the jaw beside the beak were small teeth likely used for chopping off leaves and stems. Next in the jaw was a large pair of tusks whose purpose is unknown, but it is speculated that they were used as sexual displays. The final type of teeth were tall and squared off. This type of teeth was well adapted for chewing. Chewing is relatively common in dinosaurs, but uncommon for other groups of reptiles.