The armored dinosaur known as Ankylosaurus had a tail that ended in a large, bony club. It was one of a family of plant-eating dinosaurs that walked on four legs and was protected by heavy armor. Euoplocephalus was another member of this family. Where and when Ankylosaurus livedAnkylosaurus lived 70 to 65 million years ago, during the period of the Earth's history known as the Cretaceous. Many Ankylosaurus fossils, or remains, have been found in North America, mostly in Montana, Wyoming, and in Canada. These dinosaurs lived in areas that were thick with plant life and that often surrounded bodies of water, such as lakes. Physical featuresAnkylosaurus was a stocky dinosaur that reached a length of 25 to 33 feet (7 to 10 meters), weighed up to 4 tons, and stood 4 feet (1.2 meters) tall. This dinosaur had small bony plates covering its entire body. In addition to these plates it had rows of small bony projections on its sides and bony knobs on its back. Ankylosaurus also had hornlike ridges in the upper and lower corners of its skull, just behind its eyes. It had a short, wide head and rather weak beaklike jaws with a few small teeth. Ankylosaurus stood and walked on all four of its sturdy legs. The two back legs were longer than the front two, and its feet were wide and hooflike. BehaviorAnkylosaurus was a plant eater that fed on soft and pulpy low-growing plants and shrubs. This dinosaur, like other plant-eating dinosaurs, swallowed small stones to help grind the plant material in its stomach. Ankylosaurus was a slow-moving dinosaur. It depended on the bony plates covering its body to protect it from its enemies. The club at the end of its tail was used as a weapon in self-defense. When attacked, Ankylosaurus could swing its tail with a great deal of force. Like most other dinosaurs, Ankylosaurus reproduced by laying eggs. |