Deinonychus' claws were hookers, not rippers.Deinonychus Deinonychus (dī'nənī`kəs) [Gr.,=terrible claw], swift bipedal carnivorous dinosaur of the early Cretaceous period, approximately 119–93 million years ago. Fossil specimens have been discovered in Montana and Wyoming. and its relatives, a group of bipedal bipedal adjective Capable of locomotion on 2 feet , meat-eating dinosaurs collectively known as raptors, gained a fearsome reputation because of the enlarged, sicklelike claw they had on each foot. Many paleontologists have presumed that the claw enabled the lithe predators to disembowel dis·em·bow·el tr.v. dis·em·bow·eled or dis·em·bow·elled, dis·em·bow·el·ing or dis·em·bow·el·ling, dis·em·bow·els 1. To remove the entrails from. 2. To deprive of meaning or substance. victims with a single slash, but two analyses suggest that the claws were instead used to grip and climb large prey. Deinonychus' claw was about 10 centimeters long and curved through an arc of about 16oo, almost a semicircle. In a previous study, Phillip L. Manning, a paleontologist at the University of Manchester The University of Manchester is a university located in Manchester, England. With over 40,000 students studying 500 academic programmes, more than 10,000 staff and an annual income of nearly £600 million it is the largest single-site University in the United Kingdom and receives in England, and his colleagues built a detailed model of the dinosaur's foot, equipping it with a claw made of aluminum sheathed in Kevlar and carbon-fiber composite. The researchers plunged the foot into a fresh pig carcass at speeds comparable to those expected during Deinonychus attacks. Despite having a sheath 40 times as strong as the keratin keratin (kĕr`ətĭn), any one of a class of fibrous protein molecules that serve as structural units for various living tissues. The keratins are the major protein components of hair, wool, nails, horn, hoofs, and the quills of feathers. that likely enveloped a Deinonychus claw, the model claw didn't rip a gash through the flesh. Instead, says Manning, the claw pierced the carcass and gripped the flesh but generated injuries no more than 40 millimeters deep. Those would be fatal for small prey, but trying to subdue a large dinosaur with such wounds "would be like trying to kill a person by stabbing them with plastic spoons," says Manning. Manning's team has now developed a computer model of a Deinonychus claw that combines information gleaned from computerized tomography scans of fossils with data about the strength of bone and keratin. Results suggest that the claw could support the dinosaur's full 40-kilogram weight. Manning and his colleagues suggest that raptors used their claws as climbing crampons. While latched onto the side of a large herbivore herbivore: see carnivore. herbivore Animal adapted to subsist solely on plant tissues. Herbivores range from insects (e.g., aphids) to large mammals (e.g., elephants), but the term is most often applied to ungulates. , the raptors could have used their teeth to inflict mortal wounds, they say. Lions today sometimes use a similar technique, hanging on to large prey by their claws while clamping their jaws around the victim's windpipe windpipe: see trachea. .--S.P. |
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