Naming

• The dinosaur's name, Tyrannosaurus rex, comes from ancient Greek terms specifically referring to a "tyrant lizard." In modern culture the long naming convention has been shortened to the more popular "T-Rex" but it still creates an image of a rampaging, giant lizard with lots of teeth.
  
  

Location of Habitat

• The actual ancient hunting grounds of the Tyrannosaurus rex are what is commonly known as North America today, with leftover skeletons of these huge beasts still being found in areas of the Dakotas, Montana and a number of the plains states. The time period that these dinosaurs lived is estimated by a variety of scientists, including the University of California Berkeley's program, to be somewhere between 80 and 65 million years ago, otherwise known as the Cretaceous Period.
  
  

Body Structure

• The body structure of the actual Tyrannosaurus rex consists of large rear legs, a long tail, a large head with significant teeth and small forearms. However, the significant difference between the actual animal and the fictional one is that it did not stand straight up. While the Tyrannosaurus rex did travel on its hind legs, the creature would not have remained upright for extended periods of time as previously thought. According to current scientific theory, the body joints would not have been able to carry the weight.
  
  Another fiction was the assumed speed of the Tyrannosaurus rex. Because of its size and mass, the dinosaur in fact was very slow in turning around and more than likely moved with the gait of an elephant rather than a scampering gazelle. Unlike the 40 or 50 mph movement in the movies, the Tyrannosaurus Rex had a likely slower speed of about 10 to 15 mph.
  
  

Weight and Size

• The Tyrannosaurus rex was significantly larger than many of the peer dinosaurs in the same period. At its largest, the dinosaur could reach 40 feet in length and as much as 15 feet in height. In terms of weight, a full grown dinosaur could reach as much as 16,000 pounds, according to Dino-Dictionary.com.
  
  The head was significantly large in ratio comparison with the rest of its body. There was significant muscular structure in the neck to support it, and it had enough power to crush other dinosaurs' bones.
  
  

Historical Finds

• The first documented Tyrannosaurus rex finds were in the 1890s in Colorado. Later, cranial structures were discovered in Wyoming and South Dakota. Because not much was known about the Tyrannosaurus rex at the time, these fossils were first identified as other dinosaur types before being correctly classified as those of a Tyrannosaurus rex. As of 2010, approximately 24 close-to-complete dinosaur fossils have been recovered with another 15 to 20 in various partial collections.
  
  

Hunter or Scavenger

• The current debate, again not consistent with the movies, is whether the Tyrannosaurus rex was actually a scavenger rather than a hunting dinosaur. The conclusion is not clear in scientific circles. Given the small size of its forearms, the only attacking parts were the mouth and legs. Recovered fossils have shown signs of both activities but nothing conclusive either way. The "Jurassic Park" Tyrannosaurus rex would likely be disappointed because it was portrayed as a hunter looking for the main characters to be its next dinner.