Brachiosaurus or “arm lizard” is a genus of sauropod dinosaur that lived during the Late Jurassic Period and possibly the Early Cretaceous Period 150 to 112 million years ago. It was named Brachiosaurus due to its forelimbs being shorter than its hind limbs. Brachiosaurus was discovered in 1900 by Elmer S. Riggs in the Grand River Canyon of western Colorado, United States. There are two known subspecies, and possibly three. B. altithorax was discovered in 1903 by Riggs, B. nougaredi was discovered in 1960, and B. brancai was discovered in 1914. B. nougaredi is not clearly known.
Brachiosaurus is one of the largest animals to ever walk the earth, and has become one of the most famous dinosaurs recognized worldwide. For many decades, it was believed to be the largest dinosaur known. It has since been discovered that Argentinosaurus surpasses Brachiosaurus in sheer mass. Another sauropod, Sauroposeidon, has been estimated to outweigh Brachiosaurus as well. However, Brachiosaurus is the largest dinosaur known from a nearly complete skeleton.
Based on the almost complete skeleton, Brachiosaurus measured 82 feet in length and was able to raise its head about 43 feet above ground level. Some studies of other fragmental material from larger specimens indicate that Brachiosaurus could actually grow to about 95 feet long. Brachiosaurus is estimated to weigh as much as 86 tons. This estimate is only theory and most scientists believe, based on updated body models, that the specimen is more likely to be in the range of 35 to 41 tons, and may have possibly reached up to 62 tons.
Brachiosaurus was a four-legged herbivore. It had a very long neck and tail. Its brain was very small in relation to its body size. Unlike other sauropod, it had a giraffe-like build (long forelimbs and long neck). Brachiosaurus has chisel-like teeth, which were well suited for its plant diet. The skull featured a number holes that probably may have aided in weight-reduction. It had one claw on the first toe of the front foot and its first three toes on the hind foot.
There is much speculation on whether Brachiosaurus was a warm-blooded or cold-blooded dinosaur. If it was warm-blooded, it could have grown to full size in about 10 years. If it was cold-blooded, it may have taken over 100 years to reach full size. As a warm-blooded animal, its daily energy needs would have been enormous and would have needed more than 400 pounds of food per day to survive. If cold-blooded, it could survive on far less food.
Brachiosaurus was a large dinosaur that lived on prairies filled with ferns and other similar plant life. It moved through vast conifer forests and groves of cycads. Although it is believed that Brachiosaurus traveled in herds, it was able to move individually without any fear from even the largest predators of its time (Allosaurus and Torvosaurus) because of its massive size. It was once thought that Brachiosaurus spent much of its time submerged in water to support its large mass. This speculation was due to the findings of large nasal openings in its skull placing the nostrils on top of its head, and using them like a snorkel. More current views, however, place Brachiosaurus as a fully terrestrial animal. Studies have shown that the water pressure would have prevented the animal from breathing properly and effectively, and that its feet were too narrow to be used as aquatic devices. It was also pointed out that even though the nasal openings were on top of the skull, the nostrils would most likely have been located near the snout.
In popular culture, Brachiosaurus is one of the best known among all dinosaurs. It has appeared in numerous movies and TV programs. Its most notable role was in the movie “˜Jurassic Park’ and “˜Jurassic Park III’. It also appeared in the popular documentary “˜Walking With Dinosaurs’. The asteroid 9954 Brachiosaurus was named in honor of the genus. The digital model of Brachiosaurus form “˜Jurassic Park’ was also used in the special edition release of “˜Stars Wars Episode IV: A New Hope’.