Dinosauria Online

Say hello to: APATOSAURUS

[ Apatosaurus Skeleton ]

APATOSAURUS (ah-PAT-o-sawr-us) "Deceptive Lizard" (Greek apatelos = deceptive + sauros = lizard, because its chevron bones were deceptively like those of MOSASAURUS) Also called Brontosaurus.

One of the largest of the Late Jurassic SAUROPODS. This giant four-legged plant eater had a long neck and TAIL. It measured 75 feet (23 m) from the tip of its nose to the end of its 30-foot (9.1 m) whip-like tail. It stood 15 feet (4.6 m) tall at the hips and weighed about 30 tons (27.2 metric tons). It had a small, long-snouted, horse-like head, and elephant-like FEET and legs. The front legs were shorter than the hind legs. The TEETH were small and peg-like. The BRAIN was about the size of an adult human's fist.

For a long time scientists thought Apatosaurus was too heavy to walk on land and assumed that it was a water dweller. However, recent bone studies prove that its legs could have supported its weight. It was probably a plains and forest dweller, and it probably traveled in HERDS. It ate twigs and the needles of pine, fir, and sequoia trees. Its 20-foot (6-m) neck-which had 14 or 15 vertebrae and was longer than its body--allowed it to browse on the very tops of trees.

For protection Apatosaurus relied on its SIZE and tough, leathery SKIN. (See Defense.) It lived in many areas on western North America from Montana to Baja California, as well as in Europe. Several nearly complete skeletons have been found, but only one head.

Classification: Sauropoda, Sauropodomorpha, and Saruischia