Stegosaurs Walking

Artwork by Christian Darkin/Photo Researchers, Inc.

The late Jurassic Stegosaurus, like the pair walking through a North American forest in this illustration, was a slow-moving, plant-eating dinosaur that grew as long as 30 feet (9 meters) and as much as 2 tons. Its most impressive feature was a row of large plates and tail spines down the length of its back—some more than three feet (one meter) tall.