01/26/2021 16:37 EST

Baby Dinosaur Fossil Discoveries In Alberta And Montana Provide New Insights

Fossils of younger tyrannosaurs or eggs have never been found — until now.

Forget Baby Shark, there’s an adorable new baby creature in town — or at least its fossil remains. 

Researchers have discovered the first baby tyrannosaur fossils in Alberta and Montana, and they provide a glimpse into what the babies were actually like. Plot twist: they’re super cute. 

Julius Csotonyi
An artist's rendering of what the babies might have looked like.

While you’re likely familiar with the tyrannosaurus rex (a.k.a. T-Rex), tyrannosaurs encompass a broader range of large carnivorous predatory dinosaurs including the T-Rex, Albertosaurus and others. 

Researchers discovered two fossils of interest: a small toe claw of an Albertosaurus sarcophagus found near Morrin, Alta., and a small lower jawbone of a Daspletosaurus horneri found in Montana. The claw is roughly 71.5 million years old, and the jawbone close to 75 million years old. They published their findings in the Canadian Journal of Earth Sciences this week.

Greg Funston
A diagram showing the relative size of the discoveries.

University of Alberta PhD student Mark Powers was second author on the study. He says it’s the first discovery of its kind.

“Tyrannosaurs are represented by dozens of skeletons and thousands of isolated bones or partial skeletons,” he said in a U of A news release. 

“But despite this wealth of data for tyrannosaur biology, the smallest identifiable individuals are aged three to four years old, much larger than when they would have hatched. No tyrannosaur eggs or embryos have been found even after 150 years of searching—until now.”

The unprecedented discovery will help researchers learn even more about the dinosaurs. It turns out baby tyrannosaurs were about the size of border collies and researchers learned from the fossils that they don’t fully develop their characteristic serrated teeth until later in life.

Smaller fossils and baby fossils are often harder to find, because they were more susceptible to being washed away by rivers or flood plains. Researchers plan to further explore the areas where the two specimens were found and hopefully find even more.