'The missing link': New early tyrannosaur species discovered by Calgary researchers

Bill Graveland · The Canadian Press

· Posted: Jun 11, 2025 12:56 PM EDT | Last Updated: 8 minutes ago

Scientists from the University of Calgary person discovered a caller dinosaur specimen that they accidental appears to beryllium the "missing link" successful the improvement of tyrannosaurs.

The specimen was primitively discovered successful Mongolia's Gobi Desert implicit 50 years agone successful the 1970s, but its value wasn't recognized until Darla Zelenitsky, an subordinate prof successful the university's module of science, sent postgraduate pupil Jared Voris to Mongolia connected a probe trip.

"He was determination a mates of years agone connected this probe travel and looked astatine the fossil and texted maine [that] he thought it was a caller species. I was like, 'Yay,"' Zelenitsky told The Canadian Press.

"I said, 'This is good, but we don't privation to leap the weapon connected this.' It turned retired it [was] a caller species."

Siberia to Alaska 85 cardinal years ago

The species, Khankhuuluu mongoliensis — meaning "Dragon Prince" oregon "Prince of Dragons of Mongolia" — is believed to person crossed via a onshore span from Siberia to Alaska astir 85 cardinal years ago.

Zelenitsky said it appears to beryllium connected the evolutionary standard betwixt smaller tyrannosauroids and tyrannosaurs.

"It's the missing nexus betwixt smaller tyrannosauroids and the ample predatory tyrannosaurs," she said.

"This missing nexus was astir 750 kilograms. Its ancestors were a mates of 100 kilograms and conscionable tiny, but past erstwhile you get to tyrannosaurs proper, they were implicit a 1000 kilograms, up to estimates of 5,000 kilograms."

• Dinos, conscionable drones: How caller exertion could reshape the fossil record

The findings were published Wednesday successful the British play technological diary Nature.

"It's truly breathtaking to beryllium progressive successful a find of thing that's been sitting successful a drawer for 50 years. But it's adjacent much breathtaking erstwhile it's a PhD pupil that makes that discovery," Zelenitsky added.

"This find forced america to look astatine the household histrion of tyrannosaurs successful a precise antithetic light. It ended up with america rewriting the household past of tyrannosaurs."

Right place, close time

The accomplishment of Khankhuuluu oregon a akin taxon aft moving from Asia to North America whitethorn person been the effect of pursuing their prey to a caller location, said Zelenitsky.

"It's imaginable that determination weren't galore tyrannosaur benignant predators truthful it's imaginable they were capable to instrumentality implicit that niche successful North America and moved to the apical of the nutrient chain," she said.

"Tyrannosaurs were successful the close spot astatine the close time. It allowed them to diverseness and germinate a ample assemblage size, yet becoming the monolithic apex predator that terrorized North America and Asia during the precocious Cretaceous period."

Zelenitsky said the improvement to the tyrannosaur happened rapidly, geologically speaking, and astir apt took a fewer cardinal years.

She has co-authored implicit 50 antithetic publications during her vocation and was portion of a squad that archetypal recovered grounds of feathered dinosaurs successful North America.