Heterodontosaurus

Heterodontosaurus was a small, extraordinarily specialised early ornithischian dinosaur from the Early Jurassic of southern Africa. Measuring barely over a metre long, it was about the size of a turkey with a long, slender tail. What makes Heterodontosaurus truly famous is its bizarrely mammal-like dentition. Unlike most dinosaurs, which possessed uniform teeth, it featured small nipping teeth at the front, chisel-like grinding cheek teeth, and prominent, recurved canine-like tusks. This unusual arrangement indicates a versatile diet, likely combining tough fibrous plants with roots, insects, and small animals. The limbs show adaptations for rapid bipedal running, although its strong arms and flexible hands with sharp claws might have aided in digging or grasping food. Exceptionally preserved skeletons have made Heterodontosaurus one of the most thoroughly understood basal ornithischian dinosaurs known to science.

It possessed three distinctly different types of teeth, including sharp incisors, chisel-like cheek teeth, and prominent curved tusks.

Where and when

Heterodontosaurus lived in the Early Jurassic, from 200 to 190 million years ago (Hettangian-Sinemurian age). Its remains come from South Africa and Lesotho, in the Clarens Formation.

The numbers

Length 1.1 m (estimates run from 1 to 1.2 m). Mass about 2.8 kg. Hip height about 0.4 m. That is 0.6 human-lengths, or 0.1 of a double-decker bus. These are estimates from near-complete skeleton; fields marked estimated by the site are length, mass, hip height.

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