Home > Diorama > Dinosaur Explorer > Stegosaurus The Stegosaurus (which literally means "roof-lizard") gets its name from large bony plates that jutted out from its neck, back and upper tail. Its natural "suit of armor," which it used as protection against predators (as well as to control its body temperature), also consisted of bony plates that guarded each hip, as well as two pairs of spikes that stuck out sideways from the end of its tail. Stegosaurus lived approximately 205 - 138 million years ago during the Jurassic Period. This herbivorous (plant-eating) dinosaur had short front legs with much taller hind legs. It weighed approximately 4 tons, was 9 feet tall and measured up to 30 feet in length (about the length of a modern bus). Its beak was curved and contained very small teeth that were so small and weak, that it was unable to chew the plant material that it fed on, and relied on stomach acids to completely break down its food. One Stegosaurus can be found in the diorama at Universe of Energy and is located in the "fight scene" atop a rock ledge above the vehicles on the right side.