One of the tallest of all dinosaurs, Brachiosaurus was built something like an enormous elephant with an extremely long neck. This dinosaur was tall enough to have looked over the top of a modern four-story building. The name Brachiosaurus means “arm lizard” in Latin. Scientists call it this because of its long front legs. Brachiosaurus belongs to the group of dinosaurs known as sauropods, which also includes Apatosaurus and Diplodocus. The sauropods were large, plant-eating dinosaurs with long necks, massive bodies, and four pillarlike legs to support the body. Where and when Brachiosaurus livedBrachiosaurus lived about 150 to 130 million years ago, in the late part of the geologic period known as the Jurassic and the early part of the Cretaceous. Remains of Brachiosaurus have been found in Europe and Africa, as well as in Colorado, Wyoming, and Utah in North America. Scientists once believed that Brachiosaurus, like other large sauropod dinosaurs, needed to live in water to support its massive weight. They now agree that Brachiosaurus was primarily a land animal. Its strong but lightweight bones were able to support it without the help of water. Brachiosaurus lived in areas with much plant life, especially tall trees. Physical featuresBrachiosaurus is the largest and heaviest sauropod dinosaur for which a complete skeleton has been discovered. This dinosaur could reach more than 75 feet (23 meters) in length and weighed up to 80 tons. It stood about 43 feet (13 meters) tall from its head to the ground. The most striking features of Brachiosaurus were its sloped back and its extremely long neck. Its front legs were longer than its back legs, which was a unique feature among dinosaurs. Brachiosaurus also had a relatively short tail. Its dome-shaped head was small and its snout was somewhat flat. Its nostrils were fairly large and were located near the top of its head. Brachiosaurus had a few dozen pencil-like teeth. BehaviorBrachiosaurus was a plant-eating dinosaur. Its long neck allowed it to feed from the tops of the highest trees, where other dinosaurs could not reach. Scientists believe that Brachiosaurus also fed on low-lying ground plants, such as ferns. Like other sauropod dinosaurs, Brachiosaurus had small stones in its stomach to help it grind up the plants that it ate. Brachiosaurus lived and traveled in herds. Scientists believe that Brachiosaurus could travel at speeds of about 12 to 19 miles per hour (19 to 31 kilometers per hour). Its immense size and weight, as well as sharp claws on its feet, protected it from meat-eating dinosaurs. Its tremendous height also allowed Brachiosaurus to watch for enemies coming from miles away. Young Brachiosaurus probably stayed in the center of the herd for protection. Brachiosaurus, like most other dinosaurs, reproduced by laying eggs. |