Camarasaurus (Camera-soar-us) was the most common brontosaur (sauropod dinosaur). It lived in western North America during the Jurassic Period, approximately 150 million years ago.
Camarasaurus was a medium-sized sauropod, about 60 to 75 feet in length. It was generally bulkier than other brontosaurs and had a shorter, thicker neck. The tail was also relatively short and quite different from the whip-like tail seen in such forms as Diplodocus (De-plod-i-cuss). The forelimbs and hindlimbs of Camarasaurus were of similar length so that the back of the animal was held almost horizontally.
The skull of Camarasaurus was short with a blunt snout and somewhat expanded, spatulate teeth. Since the teeth were more robust than those of Diplodocus and Brontosaurus (Bron-toe-soar-us), it is believed that Camarasaurus ate coarser plants. The nostrils were large and mounted on the top of the head in front of the eyes. A thin bar of bone separated the right and left nostril from each other. Early reconstructions of Brontosaurus featured a head very similar to that of Camarasaurus, because it was believed that the two dinosaurs were very closely related. It is now known, however, that the head of Brontosaurus was very different in appearance (see page on Brontosaurus).
An exquisitely preserved juvenile skeleton of Camarasaurus is on display at the Carnegie Museum, in Pittsburgh. It is about a quarter of the size of a full adult (17 feet) and has the distinction of being the most complete sauropod dinosaur skeleton known. Juvenile features include a shorter neck and a proportionately larger head. Camarasaurus may have traveled in small groups or in herds, as indicated by another juvenile skeleton (40 feet in length) found with two adults. However, it appears that Camarasaurus did not look after its young as eggs were deposited in lines and not collected into the safety of a nest.
A Beautifully Preserved Juvenile Skeleton of Camarasaurus at the Carniegie Museum