Who would have thought that a tyrannosaurus cub would be the same size as a dog Border Collie? At least, this is what a new research by a team of paleontologists who analyzed the first fossils of embryos of the “prima” species of T-Rex, discovered in late 2020.

According to analyzes of fossil sizes, carried out by researchers at the University of Edinburgh, Scotland, it is estimated that tyrannosaurus babies were "only" one meter long when they hatched from eggs. As adults, these creatures were able to reach 12 meters in length, weighing up to eight tons.


The bones of the puppies' jaws were approximately three centimeters in length, showing a pronounced chin characteristic in the animal and indicating that this physical aspect, characteristic of the species, was present before the animals were born. In fact, studies indicate that the puppies were very similar to their parents.

The estimated dimensions of babies Tyrannosaurs led researchers to calculate that the eggs were about 43 centimeters. Although no eggs have yet been found, the discovery can be valuable for recognizing the eggs in the future or even identifying nesting habits of the species.

Tyrannosaurus fossil
Tyrannosaurus cub jaw fossil measures just three centimeters. Photo: Greg Funston / Disclosure

Discovery Importance

Although the findings do not indicate so much information, little is known about the developmental stages of tyrannosaurs, who lived in the Land more than 70 million years ago.

As the majority of fossils found are of young or adult tyrannosaurs, studies of the species' cubs end up being unknown.


Fortunately, the jaw and claw fossils found in Canada and the United States were able to scale the appearance and size of tyrannosaurus babies and see that tyrannosaurs may have been the largest hatchling in history.

The revelations should also serve as a window for new discoveries to be made, now that paleontologists have more information and can more easily identify “traces” of the species.

Street: SlashGear

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