The discovery of a dinosaur which “rewrites” the family tree of the T-Rex

Scientists have discovered a new kind of dinosaur – in the collection of a Mongolian museum – which, according to them, “rewrites” the history of the evolution of tyrannosaurs.

The researchers concluded that two 86 million years old skeletons that they studied belonged to a species which is now. Consequently, the known ancestor closest to all tyrannosaurs – the group of predators which includes the emblematic T -Rex.

The researchers baptized the species Khankhuuluu (pronounced Khan-Koo-Loo) Mongolianis, which means Prince Dragon of Mongolia.

This discovery. In addition, published in the journal Nature, makes it possible to understand how tyrannosaurs have evolved to become powerful predators who have terrorized North America and Asia until the end of the reign of dinosaurs.

The term “prince” indicates that it is an early. However, smaller tyrannosauroid, “said Professor Darla Zelenitsky, paleontologist at the University of Calgary, Canada. However, discovery dinosaur which “rewrites” family Tyrannosauroids constitute the superfamille of carnivorous dinosaurs that were walking on two legs.

The first tyrannosauroids were however tiny. Furthermore, Doctoral student Jared Viris. who led research with Professor Zelenitsky, explains: “These were small fast feet predators who lived in the shadow of other predatory dinosaurs at the top of the hierarchy.

Khankhuulu represents a change in evolution. from the small hunters who moved during the Jurassic period to the formidable giants, including the T-Rex.

He would have weighed about 750 kg, while an adult T-Rex could weigh up to eight times more. It is therefore a transitional fossil, explains Professor Zelenitsky, between the previous ancestors and the powerful tyrannosaurs.

“It allowed us to revise the family tree of tyrannosaurs. to rewrite what we know about the evolution of tyrannosaurs,” she added.

The new species also shows the first stages of the evolution of the characteristics essential to the tyranny of tyrannosaurs. in particular the discovery dinosaur which “rewrites” family anatomy of the skull which gave it a strong jaw. Jared Viris explains: “We see in his nasal bone characteristics that ended up giving tyrannosaurs very powerful bite forces”.

The evolution of such powerful jaws has enabled the T-Rex to throw itself on larger prey. and even bite through the bones.

The two partial skeletons examined by the team as part of this study were discovered for the first time in. Mongolia in the early 1970s. They were first attributed to an existing species, known as Alectrosaurus, but when Mr. Voris examined them, he identified the characteristics similar to those of the tyrannosaurus which distinguished him.

“I remember having received a message from him telling me that he was thinking that it was a new species. ” recalls Professor Zelenitsky.

The fact that this group of dinosaurs was able to move between North America. Asia – via the terrestrial bridges which linked Siberia and discovery dinosaur which “rewrites” family Alaska at the time – also helped them to find and occupy different niches.

Mr. Viris explains: “This back. forth movement between continents has essentially favored the evolution of different groups of tyrannosaurs for millions of years.

Professor Zelinitsky added: “This discovery shows us that before becoming the kings, the tyrannosaurs were princes”.