Narrator: This is Science Today. Everyone knows that Tyrannosaurus rex was a fierce predator -- or was it? Some paleontologists think the big dinosaur was just a scavenger. Greg Erickson of the University of California, Berkeley had a chance to help decide.

Erickson: A fellow named Ken Olson who's an amateur paleontologist in Montana brought in a specimen to us of a Triceratops pelvis. This particular specimen, this pelvis, had all kinds of bite marks in it, and Ken thought that these might be Tyrannosaurus rex bite marks.

Narrator: Erickson tested that idea using a cow bone and a bronze copy of a Tyrannosaurus tooth. The tooth made marks exactly like those on the Triceratops bone, and withstood 3,000 pounds of force. So when it came to biting...

Erickson: T. rex could eclipse any animal today that's been measured, at least. What does this mean? Well, it shows that the dentition of Tyrannosaurus was capable of withstanding the kinds of forces that predators today withstand.

Narrator: Its teeth, at least, were strong enough to chomp a live animal -- more evidence that the famous dinosaur might well have been a predator after all. For Science Today, I'm Steve Tokar.