First baby tyrannosaur fossils found in Alberta, Montana

The study, led by Greg Funston, was based on two fossils: a small toe claw found in Morrin, Alta., And a small lower jaw found in Montana.

Tyrannosaurs have been the subject of extensive research, but fossils of tyrannosaur eggs or embryos have never been found – until now.

“It gives us a starting point that we didn’t have,” said Mark Powers, PhD student at the University of Alberta and the study’s second author.

“We had halfway through their growth spurt and we didn’t really have where they were coming from. Finding specimens like this, which is definitely a Tyrannosaurus in the shell or before it hatches, says a lot about this development.

What do the discoveries mean?

The unprecedented discoveries offer a lot of information to researchers.

Using a 3D scan of the fossils and measurements of the bones, the researchers were able to learn more about the sizes of the newborns and prove that the specimens are unborn tyrannosaurs.

The 71.5 million year old claw found in Alberta has what Powers called a “cartilaginous cone” on the back of the claw, which means that the area had not yet become bony and was was still in development.

The approximately 75 million-year-old jawbone found in Montana had triangular teeth with shallow roots, confirming that they were the first generation teeth of the tyrannosaurus.

“This matches a lot of other embryonic discoveries and studies of birds and other dinosaurs found in the shell, so we suspect this is an embryonic individual versus an hatched individual,” Powers said. .

The location of these fossils is also revealing.

The claw was found after a large sediment was taken during an excavation expedition to Alberta several years ago, Powers said.

In general, smaller dinosaur remains are more difficult to find.

Smaller fossils would have been more sensitive to the rivers and floodplains of the Cretaceous Period, compared to the larger dinosaur remains that are often buried deep and preserved in the sediment, Powers said.

Areas where young dinosaur fossils were found are now possible locations for other important finds, according to a professor.

“We don’t really have a skeleton, they’re relatively disjointed pieces. But because we know the area where it seems the tyrannosaurs may have made their nests, we know to go back to that place and continue with a comb it fine and find more and more stuff, ”said Scott Persons, professor of paleontology at the College of Charleston in South Carolina.

“I think it’s definitely going to happen, so eventually this grand prize of finding a tyrannosaur egg is going to happen.”