Tyrannosaurs

the T-rex has a four-foot-long jaw, six-inch-long teeth, and the huge thigh bones -- bespeaks the enormous power of //T- rex//, one of the largest theropod dinosaurs that ever existed. These 65-million-year-old bones were once arranged so that the dinosaur stood upright, propped on its tail. Based on new research, however, scientists determined that it was more accurate to show //T- rex// mounted on two feet, in a stalking position, with its head low, tail extended, and one foot slightly raised. The dinosaur in this position is equally if not more terrifying than before, with implications of speed added to its obvious strength and size.While the //T- rex// is posed as if it is stalking prey, we do not in fact know for sure whether meat-eating dinosaurs such as this were active hunters -- tracking down, attacking, and killing prey -- or scavengers, feeding on the bodies of other dinosaurs. While its huge jaws and its strong legs would certainly be forceful hunting weapons, //T- rex//'s arms were too short to reach its mouth, and its hands had only two fingers instead of three, making it unable to grasp. The fossils discovered thus far offer some evidence about whether theropods were hunters or scavengers, but not enough to answer the question.