Psittacosaurus << `siht` uh koh SAWR uhs >> was a small plant-eating dinosaur that lived in desert regions of what is now Asia. Its name, which means parrot lizard, comes from its large, sharp, parrotlike beak. The dinosaur measured up to about 2 feet (60 centimeters) tall at the hips and 6 1/2 feet (2 meters) long.
Psittacosaurus probably ran upright on its strong hind legs, which grew longer than its stout forelegs. Its long tail helped it balance. When foraging, however, the dinosaur may have walked on all fours. Short, blunt claws grew on three of the four fingers on each hand and on all four of the toes on each foot.
Psittacosaurus ate a variety of tough desert plants. It probably nipped the plants with its beak and chewed them with its sharp cheek teeth. The dinosaur may occasionally have stood on its hind legs and used its arms to pull down such food as leaves and branches. To digest the tough plants, Psittacosaurus swallowed small rocks called gastroliths. Gastroliths stayed in the dinosaur’s digestive tract and helped it grind up the food.
Psittacosaurus lived from about 130 million to 100 million years ago, during the Cretaceous Period. It probably represented one of the earliest ceratopsians (also spelled ceratopians), a group of dinosaurs that included Triceratops as well. Like all ceratopsians, Psittacosaurus had a small, triangular rostral bone at the tip of its beak. It also possessed small, primitive horns and a slight frill (bony shield) on its skull. Later ceratopsians developed large horns and elaborate frills. In addition, Psittacosaurus may have roamed in herds, a characteristic of many ceratopsians.
American scientists discovered the first nearly complete Psittacosaurus skeleton in Mongolia in 1923. Since then, other scientists have found fossils of several Psittacosaurus species across Asia.
