Ornitholestes << awr nih thuh LEHS teez >> was a small meat-eating dinosaur that lived about 150 million years ago, near the end of the Jurassic Period. The dinosaur’s name comes from the Greek words for bird and robber. Scientists once believed this dinosaur hunted mainly birds. Ornitholestes belonged to a group of dinosaurs called coelurosaurs << see LOOR uh sawrz >>, from which birds may have evolved. Coelurosaurs, in turn, belonged to a larger dinosaur group called theropods << THEHR uh pahdz >>.
Ornitholestes had a lightly built body with hollow bones. It measured about 6 feet (1.8 meters) long but weighed only about 25 pounds (11 kilograms). It stood on two legs and was a fast runner. A long, tapered tail probably helped it balance and turn quickly. Ornitholestes had a long, flexible neck and a small head. Sharp teeth rimmed the front half of its long, narrow jaws.
Ornitholestes lived in fern meadows and forests in what is now the western United States. It most likely ate lizards, small mammals, and insects. It may also have preyed on birds, birdlike dinosaurs, and flying reptiles called pterosaurs. Scientists first uncovered Ornitholestes fossils in Wyoming in 1900.
See also: Bird (The evolution of birds); Dinosaur; Theropod.
