FACT SHEET: Stegosaurus

NAME: STEGOSAURUS (STEG-ah-SAW-rus), meaning: "Covered Lizard" SIZE: 26 - 30 feet long, 9 feet tall (the size of a bus), weighed 6,800 pounds TYPE OF DIET: Herbivore (leaves from plants) WHEN: Late Jurassic period (156 - 140 million years ago) WHERE: Colorado, Wyoming, Utah (North America), Western Europe, China, Africa

Stegosaurus is one of the most famous of the great dinosaurs. It lived during the late Jurassic period. It grew to be about 26 to 30 feet long and about nine feet tall. It weighed about 6,800 pounds. Stegosaurus is known for the big plates running down its back and tail. It had 17 bony plates that grew right out of its back. The plates were arranged in two uneven rows. Stegosaurus also had spikes at the end of its flexible tail. These were about four feet long. Stegosaurus could have used its plates and spikes as protection against large meat-eating predators. It was so heavy that it couldn’t run away very quickly when a carnivore attacked. No one knows exactly how these plates were used. Some paleontologists believe that if the plates had blood vessels, then Stegosaurus could also use them to keep warm in the winter and cool in the summer. If a Stegosaur stood with its plates facing the sun, its blood would heat up and pump back into the creature’s body. Stegosaurus had a tiny brain for its body size. The brain was only about the size of a walnut. We know this by studying the space in its skull. Stegosaurus was an herbivore, meaning that it only ate plants. It didn’t have any front teeth, but a hard beak at the front of its mouth. It used this beak to snip down tough plants. It was a very successful dinosaur, meaning that it was found in many different parts of the earth.