Camptosaurus
Camptosaurus
Scientific Name: Camptosaurus dispar, meaning "flexible lizard"
Time Period: 147 million years ago, Jurassic
Our skeleton of Camptosaurus went on display at the museum around 1965 and was the Museum’s second dinosaur skeleton. Originally, it was mounted in the kangaroo pose on its hind legs and using its tail as a prop. It was remounted into a new four-legged pose in 2013 . The skeleton is 17¾ feet long and 5 feet tall at the hips. It is a plaster of Paris cast of bones collected from the Cleveland Lloyd Dinosaur Quarry, about 30 miles south of Price.
Camptosaurus was a distant relative of Iguanodon, the dinosaur with the thumb-spike. In fact, the thumb (digit 1) of Camptosaurus had little movement and the claw was almost like a spike . At one time, it was thought that Camptosaurus was bipedal, using its long tail that made up about 50% its total length as a counterbalance, as in Allosaurus. To keep the tail straight out from the body, there are bone tendons embedded in the muscles of the back and tail. Similar tendons are seen today in the drumstick of a turkey. Despite the stiff tail, it seems doubtful that Camptosaurus walked bipedally because the front of the body is massive to accommodate a large digestive gut. This means that Camptosaurus was too front heavy to walk on hind legs; although, the smaller juveniles might have been able to do so.
The skull of Camptosaurus is about 15 inches long. It has no teeth at the front of the beak and broad crushing teeth in the cheeks. These teeth are made stronger by ridges on the outer surface. Chewing causes these teeth to have a flat, grinding surface. Unlike Allosaurus, these teeth cannot slice through flesh, but they can pulverize vegetation.
The pelvis is rather broad for its length and the upper bone, called the ilium, bows outwards.
The hand of Camptosaurus has five digits, but only fingers 1, 2, and 3 have claws. The outer digits, fingers 4 and 5, have small nubs instead. Overall, the hand is a stiff structure with little movement possible between the joints. This makes the hand an ideal weight-bearer, but useless for grabbing vegetation.