Scientists Uncovering Holes in T-Rex Armor

Even the mighty Tyrannosaurus rex can’t escape the merciless progress of scientific knowledge. The truth is cruel: T-rex was probably T-wrecks.

“If we did Jurassic Park 4,” says Wyoming paleontologist Robert Bakker, “T-rex would be portrayed in a fear-, angst-ridden role--sort of a large Woody Allen character.”

The fearsome thunder-lizards lived wretched lives, he said: “They were beat up, limping, had oozing sores, were dripping pus and disease-ridden, and had to worry about their children starving and other T-rexes coming in and kicking them out.”

Bakker, of the Wyoming Dinosaur Society, knows this because of research by Elizabeth Rega, a physical anthropologist at Western University in Pomona, Calif.

Rega has studied ancient diseases in people and began applying her knowledge to dinosaurs a few years ago. She presented her theory to more than 350 peers at the annual meeting of the Society of Vertebrate Paleontology, which concluded Oct. 6 at Montana State University.

Rega and University of Iowa paleontologist Chris Brochu examined three T-rex skeletons, including Sue, one of the most complete specimens in the world. They found signs of diseases common to many mammals.

“These diseases were most likely chronic, long-term, non-life-threatening infections,” Rega said.

Cattle ranchers might recognize one of them: T-rex shows signs of “lumpy jaw,” an infection in the back of the jaw afflicting many cattle today.

For years, paleontologists have speculated that holes commonly found on T-rex’s lower jaw were bite marks left by other T-rexes in fights over food.

“If they’re bite marks, it doesn’t make sense that they occur on so many in the same place,” Rega said. And such bites on the back of the head would be difficult, she said.

Rega stressed that her theory is only that, and the holes could be from cancer, bone cysts or a fungal infection.

But lumpy jaw wasn’t Sue’s only ailment. Her lower leg bone had an infection that healed but probably leaked pus at times.

“I don’t know if this would have debilitated the animal, but it probably would have been really smelly in life,” Rega said.

Sue also had several broken ribs, and several bones in her spine and tail had stiffened and begun to fuse. But strangely enough, the marks on her bones indicate she was healthy.

“Most diseases kill without leaving a mark on the bones,” she said. “They’re healthy because they’re living with it.”

In addition, the jaw infection might have served a practical purpose, Rega said. Infections give some animals, such as a Komodo dragon, what amounts to a “venom” that kills their prey within days after a bite.

“Could T-rex inflict a bite, then wait around for two days for the animal to die?” she speculated.

Rega’s research indicates that T-rex healed more like a mammal than a reptile. That bolsters paleontologists who theorize some dinosaurs were warm-blooded.