Tyrannosaurus Rex
Tyrannosaurus Rex
Tyrannosaurus rex (T. rex), was a meat-eating (canivorous) dinosaur, and is the most famous of the Tryannosaurids (tyrant reptile). Despite its popularity, T. rex appears to have had a limited range in North America and Asia, and existed for a relatively short period of time. T. rex appeared during the late Cretaceous period, about 85 million to 65 million years ago. This was toward the end of the Mesozoic era or the Age of Reptiles, and just prior to the dinosaurs’ extinction.
Based on fossils, T. rex weighed 5-6 tons, stood about 15 feet (4 m) tall, was 20-46 ft (6.5-15 m) long, and had 6-in (15 cm) long, sharp, and jagged teeth.
Its skull was one-piece, with no moving parts except at the joint of the jaw. The compartments in the skull and in the lower jaw that housed the muscles were enlarged more than in any other predator. Its snout was sharply pinched to clear its field of vision. Its eyes faced forward to provide some overlap between visual fields from the right and left eyes, permitting stereoscopic vision.
This lizard-hipped dinosaur walked upright on two powerful hind legs, which ended in birdlike feet (indeed, it may have been evolutionarily related to birds, complete with the possession of feathers for a time during its development) with three forward-pointing toes with large claws. These were its weapons. Evolution shortened its torso for balance and speed. Some say the beast was surprisingly slender-limbed, graceful, and fast, able to attack other slower plant-eating dinosaurs such as the Triceratops. Although it possessed two small and muscular forelimbs, many paleontologists believe they were of little practical use.
Resources
BOOKS
Cohen, Daniel. Tyrannosaurus Rex. Mankato, MN:Capstone Press, 2006.
Kim, Sam. Tyrannosaurus Rex. Seoul: Kobook Limited, 2003.
Matthews, Rupert. Gone Forever: Tyrannosaurus Rex. New York: Heinemann, 2004.
Laurie Toupin