Tryannosaurus Rex Behavior
Some aspects of the Tyrannosaurus, however, were not so obvious. For example, early paleontologists were not sure how T. rex moved. The first reconstructions of T. rex skeletons showed the dinosaur standing upright with its tail resting on the ground. Likewise, paintings in books and museum exhibits portrayed the giant creatures as fierce but thick-bodied and sluggish. By the 1970's, however, paleontologists had determined, from the shape and position of Tyrannosaurus pelvis and leg bones, that a T. rex moved about with its body parallel to the ground. The animal held its long tail up in the air as a counterbalance to its large head.
Other clues to the way T. rex moved came from studies of the leg bones where tendons had attached muscles to the bone. The size of the markings suggested that the leg muscles were quite powerful--not the muscles of a creature that plodded along. Far from being sluggish, paleontologists concluded, T. rex was actually quite agile. Similar findings about the anatomy of other dinosaur species led researchers to conclude that dinosaurs in general were active animals.
Because of this new interpretation, paleontologists began to rethink their assumptions about the physiology of dinosaurs. They had long assumed that all dinosaurs were cold-blooded, like modern reptiles. A cold-blooded animal's body temperature changes with the temperature of the environment, and its level of activity changes with its body temperature. A lizard, for example, is active when its body is warm and sluggish when it is cool. Warm-blooded animals, such as birds and mammals, maintain relatively constant body temperatures, tend to be more active, and--like dinosaurs--have anatomies that allow for active lives.
Find Your Perfect Pet
Comments