Kansas Paleontologists Uncover Mysterious Juvenile T-Rex Fossil, Sparking Questions About Its Origins and Untold History

A full set of teeth in the fossil’s upper jaw were found, along with fragments of hip and skull bones.

It was in Hell Creek that researchers from the University of Kansas recently stumbled on the remains of a young Tyrannosaurus rex—they think.

“We just set off prospecting and a student came across some bone fragments,” says David Burnham, a paleontologist from the University of Kansas. In Hell Creek, you’re bound to find them. “If you put a black dot on the map for every fossil found in that area, it would be all black.”

Fossils from various periods have been found there, and this isn’t the first T. rex fossil to be found, but University of Kansas scientists think it could be one of the most intact. The entire fossil remains of the upper part of the dinosaur’s jaw, with all its teeth, was found.

“Our young selves look nothing like we do as adults,” he says, noting, for instance, the degrees to which a skull can change shape in a person’s lifetime. He says the same is true for T. rex, though it can be difficult to know how exactly those skeletons change because so few juveniles have been found.

Further work will determine whether the team actually has a T. rex on their hands, or possibly a Nanotyrannus, a tiny genus of tyrannosaur that’s a matter of scientific debate. Many paleontologists think that so-called Nanotyrannus fossils are actually juvenile T. rex specimens.

While the skeleton fragments they do have are helping craft a clearer picture of what the dinosaur was, Burnham says they’re not done digging it up. This summer, he and his research team plan to return to the site where it was found.

“We’d like to find a femur or tibia,” he says, but adds they’ll be looking for all of its remains.