T-Rex’s older cousin – the Reaper of Death

Thanatotheristes degrootorum is thought to be the oldest member of the T-Rex family.

The world of paleontology is always full of surprises, and it’s not every day that a new species of dinosaur is discovered. On February 6th, 2023, researchers announced that they had found a new species of dinosaur that is closely linked to the Tyrannosaurus rex.

T-Rex's older cousin - the Reaper of Death 1
Roaring dinosaur scene 3D illustration. © Warpaintcobra/Istock

Thanatotheristes degrootorum, which translates to “Reaper of Death” in Greek, is estimated to be the oldest member of the T-Rex family that has been discovered in northern North America so far. It would have reached a length of around eight meters (26 feet) in its adult stage.

“We chose a name that embodies what this tyrannosaur was as the only known large apex predator of its time in Canada, the reaper of death,” said Darla Zelenitsky, assistant professor of Dinosaur Palaeobiology at the Canada’s University of Calgary. “The nickname has come to be Thanatos,” she told AFP.

Thanatotheristes degrootorum
Life restoration of Thanatotheristes degrootorum. © Wikimedia Commons

Whereas T-Rex — the most famous of all dinosaur species, immortalized in Steven Spielberg’s 1993 epic Jurassic Park — stalked its prey around 66 million years ago, Thanatos dates back at least 79 million years, the team said. The specimen was discovered by Jared Voris, a PhD student at Calgary; and it is the first new tyrannosaur species found in 50 years in Canada.

“There are very few species of tyrannosaurids, relatively speaking,” said Zelenitsky, co-author of the study that appeared in the journal Cretaceous Research. “Because of the nature of the food chain these large apex predators were rare compared to herbivorous or plant-eating dinosaurs.”

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When doctoral student Jared Voris tried to identify the species and genus, the upper and lower jaw bones of the “Reaper of Death” went unstudied for years. © Jared Voris

The study found that Thanatos had a long, deep snout, similar to more primitive tyrannosaurs that lived in the southern United States. The researchers suggested that the difference in tyrannosaur skull shapes between regions could have been down to differences in diet, and dependant on the prey available at the time.

The discovery of a new species of dinosaur is an exciting moment for anyone interested in paleontology. The Reaper of Death, the newly discovered cousin of the Tyrannosaurus rex, is a fascinating addition to the family tree of dinosaurs.

We hope you’ve enjoyed learning about this incredible discovery and how it fits into the larger picture of dinosaur evolution. Keep an eye out for further updates and research on this fascinating creature, and who knows what other surprises the world of paleontology may have in store for us in the future!