In Late Jurassic North America, the most common large predator was the 1.5
ton Allosaurus fragilis . The specialized skull of this theropod had a
hinged lower jaw that expanded sideways, and a joint in the snout that allowed
the front of the skull to move up and down independently of the rear; this
allowed Allosaurus to swallow huge pieces of meat in a single bite.
Allosaurus is known from thousands of bones that ranged in size from
those belonging to juvenile specimens 10 feet long to bones from 40 foot
adults.
Illustration © 1992/2000 Brian Franczak
Text © 1998 Brian
Franczak
