Latest news with #tyrannosaurs
Yahoo
2 days ago
- Science
- Yahoo
New species of dinosaur discovered that 'rewrites' T.rex family tree
Scientists have discovered a new species of dinosaur - in the collection of a Mongolian museum - that they say "rewrites" the evolutionary history of tyrannosaurs. Researchers concluded that two 86 million-year-old skeletons they studied belonged to a species that is now the closest known ancestor of all tyrannosaurs - the group of predators that includes the iconic The researchers named the species Khankhuuluu (pronounced khan-KOO-loo) mongoliensis, meaning Dragon Prince of Mongolia. The discovery, published in Nature, is a window into how tyrannosaurs evolved to become powerful predators that terrorised North America and Asia until the end of the reign of the dinosaurs. "'Prince' refers to this being an early, smaller tyrannosauroid," explained Prof Darla Zelenitsky, a palaeontologist from the University of Calgary in Canada. Tyrannosauroids are the superfamily of carnivorous dinosaurs that walked on two legs. The first tyrannosauroids though were tiny. PhD student Jared Voris, who led the research with Prof Zelenitsky, explained: "They were these really small, fleet-footed predators that lived in the shadows of other apex predatory dinosaurs." Khankhuuluu represents an evolutionary shift - from those small hunters that scampered around during the Jurassic period - to the formidable giants, including T-rex. It would have weighed about 750kg, while an adult could have weighed as much as eight times that, so "this is a transitional [fossil]," explained Prof Zelenitsky, "between earlier ancestors and the mighty tyrannosaurs". "It has helped us revise the tyrannosaur family tree and rewrite what we know about the evolution of tyrannosaurs," she added. The new species also shows early evolutionary stages of features that were key to the tyrannosaurs' tyranny, including skull anatomy that gave it a strong jaw. Jared Voris explained: "We see features in its nasal bone that eventually gave tyrannosaurs those very powerful bite forces." The evolution of such powerful jaws allowed T-rex to pounce on larger prey, and even bite through bone. Tyrannosaur's last meal was two baby dinosaurs Fossil reveals 240 million year-old 'dragon' Solving the mystery of a dinosaur mass grave The two partial skeletons that the team examined in this study were first discovered in Mongolia back in the early 1970s. They were initially assigned to an existing species, known as Alectrosaurus, but when Mr Voris examined them, he identified the Tyrannosaur-like features that set it apart. "I remember getting a text from him - that he thought this was a new species," recalled Prof Zelenitsky. The fact that this group of dinosaurs were able to move between North America and Asia - via land bridges that connected Siberia and Alaska at the time - also helped them to find and occupy different niches. Mr Voris explained: "That movement back and forth between the continents basically pushed the evolution of different tyrannosaur groups" over millions of years. Prof Zelinitsky added: "This discovery shows us that, before tyrannosaurs became the kings, they were they were princes."
CBC
3 days ago
- Science
- CBC
'The missing link': New early tyrannosaur species discovered by Calgary researchers
Scientists from the University of Calgary have discovered a new dinosaur specimen that they say appears to be the "missing link" in the evolution of tyrannosaurs. The specimen was originally discovered in Mongolia's Gobi Desert over 50 years ago in the 1970s, but its significance wasn't recognized until Darla Zelenitsky, an associate professor in the university's faculty of science, sent graduate student Jared Voris to Mongolia on a research trip. "He was there a couple of years ago on this research trip and looked at the fossil and texted me [that] he thought it was a new species. I was like, 'Yay,"' Zelenitsky told The Canadian Press. "I said, 'This is good, but we don't want to jump the gun on this.' It turned out it [was] a new species." Siberia to Alaska 85 million years ago The species, Khankhuuluu mongoliensis — meaning "Dragon Prince" or "Prince of Dragons of Mongolia" — is believed to have crossed via a land bridge from Siberia to Alaska roughly 85 million years ago. Zelenitsky said it appears to sit on the evolutionary scale between smaller tyrannosauroids and tyrannosaurs. "It's the missing link between smaller tyrannosauroids and the large predatory tyrannosaurs," she said. "This missing link was around 750 kilograms. Its ancestors were a couple of hundred kilograms and just tiny, but then when you get to tyrannosaurs proper, they were over a thousand kilograms, up to estimates of 5,000 kilograms." The findings were published Wednesday in the British weekly scientific journal Nature. "It's really exciting to be involved in a discovery of something that's been sitting in a drawer for 50 years. But it's even more exciting when it's a PhD student that makes that discovery," Zelenitsky added. "This discovery forced us to look at the family tree of tyrannosaurs in a very different light. It ended up with us rewriting the family history of tyrannosaurs." Right place, right time The arrival of Khankhuuluu or a similar species after moving from Asia to North America may have been the result of following their prey to a new location, said Zelenitsky. "It's possible that there weren't many tyrannosaur type predators so it's possible they were able to take over that niche in North America and moved to the top of the food chain," she said. "Tyrannosaurs were in the right place at the right time. It allowed them to diversity and evolve a large body size, ultimately becoming the massive apex predator that terrorized North America and Asia during the late Cretaceous period." Zelenitsky said the evolution to the tyrannosaur happened rapidly, geologically speaking, and probably took a few million years. She has co-authored over 50 different publications during her career and was part of a team that first found evidence of feathered dinosaurs in North America.
