Allosaurus

One of the most famous Jurassic dinosaurs, Allosaurus(other lizard) is often called the lion of the Jurassic. This killer has been found in North America, Europe, and Africa. Allosaurus lived about 145-155 million years ago.

Description
Allosaurus had the basic large theropod body plan. Its large head was filled with dozens of sharp teeth and it's powerful legs could propel it at blazing speeds exceeding 20 miles an hour. Its long arms ended in three fingers, all tipped with a large claw over 6 inches long. Allosaurus is famous for its eye crests.

Size
Many skeletons of Allosaurus have been found and these show a wide size range. Some as small as 26 feet(8 meters) long and 1 ton are known. Others as high as 36-40 feet(11-12 meters) long and 4 tons have also been found. Most adults averaged about 30-36 feet(9-11 meters) in length and weighed in the range of 2-3 tons.

Hunting and Competition
Allosaurus was a top predator of the late Jurassic. It would have preyed on dinosaurs like stegosaurs, ornithopods, and sauropods. It's thought that Allosaurus may have hunted in packs. The late Jurassic was home to many large carnivores. Giants like Ceratosaurus and Torvosaurus would have been competition for Allosaurus, although Allosaurus was much more common.

Bite
Allosaurus and its cousins did not have very powerful "standard" bites. However, some evidence suggests that Allosaurus could open it's jaws like a snake and use its upper jaw like a hatchet. It would then use its powerful neck muscles to swing its jaw down like an ax. This could produce a force exceeding 3,000 pounds per square inch.

In Popular Culture
Allosaurus has been featured in the media for years. It was one of the first really big carnivores found. Allosaurus has appeared in a number of documentaries like When Dinosaurs Roamed America, Walking With Dinosaurs, and Planet Dinosaur, just to name a few. A few books also have the animal. Some video games like Jurassic Park: Operation Genesis feature Allosaurus. Allosaurus' future in popular culture looks bright.