Latest news with #Khankhuuluu
Sinar Daily
22-06-2025
- Science
- Sinar Daily
New T-Rex ancestor discovered in drawers of Mongolian institute
The fossils were first dug up in southeastern Mongolia in the early 1970s but at the time were identified as belonging to a different tyrannosaur, Alectrosaurus. 21 Jun 2025 06:00pm This handout artist's illustration made available by University of Calgary on June 6, 2025, shows the newly discovered dinosaur species Khankhuuluu mongoliensis, an ancestor of Tyrannosaurus Rex. Misidentified bones that languished in the drawers of a Mongolian institute for 50 years belong to a new species of tyrannosaur that rewrites the family history of the mighty T-Rex, scientists said on June 11, 2025. (Photo by Julius CSOTONYI / University of Calgary / AFP) PARIS - Misidentified bones that languished in the drawers of a Mongolian institute for 50 years belong to a new species of tyrannosaur that rewrites the family history of the mighty T-Rex, scientists said Wednesday. This slender ancestor of the massive Tyrannosaurus Rex was around four metres (13 feet) long and weighed three quarters of a tonne, according to a new study in the journal Nature. "It would have been the size of a very large horse," study co-author Darla Zelenitsky of Canada's University of Calgary told AFP. The fossils were first dug up in southeastern Mongolia in the early 1970s but at the time were identified as belonging to a different tyrannosaur, Alectrosaurus. For half a century, the fossils sat in the drawers at the Institute of Paleontology of the Mongolian Academy of Sciences in the capital Ulaanbaatar. Then PhD student Jared Voris, who was on a trip to Mongolia, started looking through the drawers and noticed something was wrong, Zelenitsky said. It turned out the fossils were well-preserved, partial skeletons of two different individuals of a completely new species. "It is quite possible that discoveries like this are sitting in other museums that just have not been recognised," Zelenitsky added. 'Messy' family history They named the new species Khankhuuluu mongoliensis, which roughly means the dragon prince of Mongolia because it is smaller than the "king" T-Rex. Zelenitsky said the discovery "helped us clarify a lot about the family history of the tyrannosaur group because it was really messy previously". The T-Rex represented the end of the family line. It was the apex predator in North America until 66 million years ago, when an asteroid bigger than Mount Everest slammed into the Gulf of Mexico. Three quarters of life on Earth was wiped out, including all the dinosaurs that did not evolve into birds. Around 20 million years earlier, Khankhuuluu -- or another closely related family member -- is now believed to have migrated from Asia to North America using the land bridge that once connected Siberia and Alaska. This led to tyrannosaurs evolving across North America. Then one of these species is thought to have crossed back over to Asia, where two tyrannosaur subgroups emerged. One was much smaller, weighing under a tonne, and was nicknamed Pinocchio rex for its long snout. The other subgroup was huge and included behemoths like the Tarbosaurus, which was only a little smaller than the T-rex. One of the gigantic dinosaurs then left Asia again for North America, eventually giving rise to the T-Rex, which dominated for just two million years -- until the asteroid struck. - AFP
Japan Forward
19-06-2025
- Science
- Japan Forward
New Tyrannosauroid Species Offers Clues to Dino Evolution
A species of tyrannosauroid was discovered among fossils excavated from Late Cretaceous rock layers in Mongolia. The fossil dates back approximately 90 million years. The international research team behind the discovery included researchers from Hokkaido University, the University of Calgary in Canada, and other institutions. They named the species Khankhuuluu mongoliensis and published their findings in the June 12 issue of the British scientific journal Nature . This discovery offers a new perspective on the origin and evolution of tyrannosaurs. The team explained that this new species was actually discovered among fossils collected around 50 years ago in Mongolia's Gobi Desert. Khankhuuluu had a slender body, similar to juvenile tyrannosaurs, and weighed less than 500 kilograms (1102 lbs). Its leg shape and other features were distinct enough from known tyrannosaurs to classify it as a new species. A robot of a Tyrannosaurus at the Ibaraki Nature Museum in 2018. (©Sankei by Takeo Kusashita) Tyrannosauridae is a family of dinosaurs that comprises two subfamilies, including the Tyrannosaurus. Until the discovery of Khankhuuluu, it was believed that tyrannosaurs originated in North America. However, the new evidence suggests their ancestors first appeared in Asia and later migrated back and forth between Asia and North America, evolving into larger forms over time. Moreover, Khankhuuluu is thought to be the common ancestor not only of large tyrannosaurs but also of Alioramus , a related species weighing around 750 kilograms, offering important clues about their evolution. Professor Kaiji Kobayashi from the Hokkaido University Museum, part of the research team, said, "The discovery of Khankhuuluu has clarified the origin and evolutionary process of large tyrannosaurs. We plan to continue our research to better understand the migration routes tyrannosaurs took between Asia and North America." ( Read the article in Japanese . ) Author: The Sankei Shimbun
Yahoo
13-06-2025
- Science
- Yahoo
Scientists discover ‘dragon prince' dinosaur, the T. Rex's missing ancestor
Tyrannosaurus rex is a carnivorous icon. Exceeding 40 feet in length and nine tons, the bone-crushing giant stands out as the largest and last of its meat-eating family. Now a new and far smaller tyrannosaur is filling in the famous dinosaur's evolutionary backstory. The newest addition to the tyrannosaur family tree is named Khankhuuluu mongoliensis, which translates to 'dragon prince from Mongolia.' Described this week in the journal Nature, the dinosaur has been identified for the first time from two partial skeletons that include skull bones, vertebrae, part of the hips, and limb bones. Altogether, the pieces reveal a slender tyrannosaur that roamed Cretaceous Mongolia about 86 million years ago and was about 13 feet long—or about the size of juvenile T. rex that would stalk North America 20 million years later. In fact, Khankhuuluu even looked like a juvenile of later, larger tyrannosaurs, with round eye sockets, blade-like teeth, and long, shallow jaws better suited to biting fast rather than hard. (T. rex had lips, upending its enduring pop culture image.) Khankhuuluu does more than simply add another dinosaur to the ever-growing roster of dinosaurs. 'Khankhuuluu gives us the origin story of tyrannosaurs,' says University of Calgary paleontologist and study co-author Darla Zelenitsky. In the early 1970s, Mongolian paleontologist Altangerel Perle found a pair of partial tyrannosaur skeletons in the eastern part of the country. The bones seemed similar to a small tyrannosaur that had been named before, Alectrosaurus. But when University of Calgary paleontologist and study co-author Jared Voris studied the bones during a research trip to Mongolia in 2023, he soon realized that the bones did not belong to Alectrosaurus at all. The bones from the two skeletons belonged to a new form of tyrannosaur that had been waiting to be discovered in collections for half a century. 'It had features like a hollow air chamber in side its nasal bone, which no other tyrannosaur species has,' Voris says. The fossils deserved a new name and have been recategorized as Khankhuuluu. Voris has found tyrannosaurs hiding in plain sight before. In 2020, Voris and colleagues named the 80 million-year-old tyrannosaur Thanatotheristes from bones assigned to another species found in Alberta. ("Reaper of Death" tyrannosaur discovered in Canada.) The finds are part of a burgeoning array of tyrannosaur discoveries. Instead of a simple line of evolution from early tyrannosaurs to T. rex, paleontologists have uncovered a wildly branching evolutionary bush of different tyrannosaur subgroups that came and went through the Cretaceous. The glut of new tyrannosaur species is allowing experts to piece together how big tyrannosaurs, including the gigantic T. rex, evolved and spread across vast stretches of the planet. When compared to other tyrannosaurs, the researchers found that Khankhuuluu is a close relative of the broader group of tyrannosaurs that include Gorgosaurus from Alberta, the bumpy-snouted Alioramus from Mongolia, and the iconic T. rex. The new family tree, as well as where the fossils were uncovered, create an updated picture of how tyrannosaurs evolved over 20 million years.'It is a pivotal species in understanding the evolutionary success of T. rex and its relatives,' says University College London paleontologist Cassius Morrison, who was not involved in the new study. In particular, the new analysis reveals how tyrannosaurs evolved into many different species as the carnivores wandered into new around the time of Khankhuuluu, Voris and colleagues propose, such small, slender tyrannosaurs were dispersing from prehistoric Asia into North America over a land bridge. 'Tyrannosaurs evolved into those giant apex predators and diversified very rapidly across North America,' Voris says, the first of what Zelenitsky calls 'two explosions of tyrannosaurs.' Some of the predators remained slender and chased smaller prey while others became bulkier and hunted larger dinosaurs, and they roamed habitats from southern California to New Jersey. (See how these fierce dinos evolved in our pages over 100 years.) The new study suggests, however, that the direct ancestors of T. rex, did not evolve in North America. Voris and colleagues propose that around 79 and 78 million years ago at least one lineage of tyrannosaurs ventured back into Asia. The researchers know this because of the close relationship of two tyrannosaur groups that at a glance might seem very different. When tyrannosaurs returned to Asia during this period and underwent their second explosion, one group was relatively slender and had long snouts decorated with small horns, like the 'Pinocchio' dinosaur Qianzhousaurus. The other group began to grow larger, with deep skulls adept at crushing bones, like Tarbosaurus. T. rex evolved from ancestors in the second group, a lineage of bone-crushers that once again crossed the land bridge back into North America between 73 and 67 million years ago—making T. rex a new form of predator that arrived from another continent. 'The new analysis provides strong support that the ancestors of T. rex evolved from a group of tyrannosaurs that ventured back to Asia after they had undergone an evolutionary radiation in North America,' Morrison says. Ultimately, the study suggests that the rise of one of Earth's largest carnivores was due to a back-and-forth between North America and Asia that took place over a period of 20 million years. Had a devastating asteroid impact not abruptly ended the Cretaceous 66 million years ago, tyrannosaurs would have undoubtedly kept changing.
National Geographic
12-06-2025
- Science
- National Geographic
Scientists discover ‘dragon prince' dinosaur, the T. Rex's missing ancestor
Khankhuuluu mongoliensis was slender with features like no other member of the tyrannosaur family tree. This illustration depicts how the slender Khankhuuluu mongoliensis may have appeared as it roamed Mongolia during the Cretaceous period. The newest addition to the tyrannosaur family, the discovery of this "dragon prince from Mongolia" sheds light on the origins of Tyrannosaurus rex. Illustration by Julius Csotonyi Tyrannosaurus rex is a carnivorous icon. Exceeding 40 feet in length and nine tons, the bone-crushing giant stands out as the largest and last of its meat-eating family. Now a new and far smaller tyrannosaur is filling in the famous dinosaur's evolutionary backstory. The newest addition to the tyrannosaur family tree is named Khankhuuluu mongoliensis, which translates to 'dragon prince from Mongolia.' Described this week in the journal Nature, the dinosaur has been identified for the first time from two partial skeletons that include skull bones, vertebrae, part of the hips, and limb bones. Altogether, the pieces reveal a slender tyrannosaur that roamed Cretaceous Mongolia about 86 million years ago and was about 13 feet long—or about the size of juvenile T. rex that would stalk North America 20 million years later. In fact, Khankhuuluu even looked like a juvenile of later, larger tyrannosaurs, with round eye sockets, blade-like teeth, and long, shallow jaws better suited to biting fast rather than hard. (T. rex had lips, upending its enduring pop culture image.) Khankhuuluu does more than simply add another dinosaur to the ever-growing roster of dinosaurs. 'Khankhuuluu gives us the origin story of tyrannosaurs,' says University of Calgary paleontologist and study co-author Darla Zelenitsky. Comparing the fossils of mature Khankhuuluu (a, d, g) with fossils of mature Gorgosaurus (c, f, i) and juvenile Gorgosaurus (b, e, h) provides new insights into the evolutionary lineage between the smaller-bodied tyrannosauroids, such as Khankhuuluu, and the larger eutyrannosaurians like Gorgosaurus and Tyrannosaurus. Silhouettes compare the sizes of Khankhuuluu (left) with a juvenile (right) and adult (middle) Gorgosaurus. Scale bars, 5 cm (individual elements) and 1 m (silhouette). Illustration by Voris et al. (2025), Nature In the early 1970s, Mongolian paleontologist Altangerel Perle found a pair of partial tyrannosaur skeletons in the eastern part of the country. The bones seemed similar to a small tyrannosaur that had been named before, Alectrosaurus. But when University of Calgary paleontologist and study co-author Jared Voris studied the bones during a research trip to Mongolia in 2023, he soon realized that the bones did not belong to Alectrosaurus at all. The bones from the two skeletons belonged to a new form of tyrannosaur that had been waiting to be discovered in collections for half a century. 'It had features like a hollow air chamber in side its nasal bone, which no other tyrannosaur species has,' Voris says. The fossils deserved a new name and have been recategorized as Khankhuuluu. Voris has found tyrannosaurs hiding in plain sight before. In 2020, Voris and colleagues named the 80 million-year-old tyrannosaur Thanatotheristes from bones assigned to another species found in Alberta. ("Reaper of Death" tyrannosaur discovered in Canada.) The finds are part of a burgeoning array of tyrannosaur discoveries. Instead of a simple line of evolution from early tyrannosaurs to T. rex, paleontologists have uncovered a wildly branching evolutionary bush of different tyrannosaur subgroups that came and went through the Cretaceous. The glut of new tyrannosaur species is allowing experts to piece together how big tyrannosaurs, including the gigantic T. rex, evolved and spread across vast stretches of the planet. What the 'dragon prince' tells us about the evolution of T. rex When compared to other tyrannosaurs, the researchers found that Khankhuuluu is a close relative of the broader group of tyrannosaurs that include Gorgosaurus from Alberta, the bumpy-snouted Alioramus from Mongolia, and the iconic T. rex. The new family tree, as well as where the fossils were uncovered, create an updated picture of how tyrannosaurs evolved over 20 million years. 'It is a pivotal species in understanding the evolutionary success of T. rex and its relatives,' says University College London paleontologist Cassius Morrison, who was not involved in the new study. In particular, the new analysis reveals how tyrannosaurs evolved into many different species as the carnivores wandered into new landscapes. Sometime around the time of Khankhuuluu, Voris and colleagues propose, such small, slender tyrannosaurs were dispersing from prehistoric Asia into North America over a land bridge. 'Tyrannosaurs evolved into those giant apex predators and diversified very rapidly across North America,' Voris says, the first of what Zelenitsky calls 'two explosions of tyrannosaurs.' Some of the predators remained slender and chased smaller prey while others became bulkier and hunted larger dinosaurs, and they roamed habitats from southern California to New Jersey. (See how these fierce dinos evolved in our pages over 100 years.) The new study suggests, however, that the direct ancestors of T. rex, did not evolve in North America. Voris and colleagues propose that around 79 and 78 million years ago at least one lineage of tyrannosaurs ventured back into Asia. The researchers know this because of the close relationship of two tyrannosaur groups that at a glance might seem very different. When tyrannosaurs returned to Asia during this period and underwent their second explosion, one group was relatively slender and had long snouts decorated with small horns, like the 'Pinocchio' dinosaur Qianzhousaurus. The other group began to grow larger, with deep skulls adept at crushing bones, like Tarbosaurus. T. rex evolved from ancestors in the second group, a lineage of bone-crushers that once again crossed the land bridge back into North America between 73 and 67 million years ago—making T. rex a new form of predator that arrived from another continent. 'The new analysis provides strong support that the ancestors of T. rex evolved from a group of tyrannosaurs that ventured back to Asia after they had undergone an evolutionary radiation in North America,' Morrison says. Ultimately, the study suggests that the rise of one of Earth's largest carnivores was due to a back-and-forth between North America and Asia that took place over a period of 20 million years. Had a devastating asteroid impact not abruptly ended the Cretaceous 66 million years ago, tyrannosaurs would have undoubtedly kept changing.
CNN
12-06-2025
- Science
- CNN
‘Dragon prince' dinosaur discovery is changing how scientists understand T. rex
Sign up for CNN's Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. CNN — Scientists have identified a previously unknown 86 million-year-old dinosaur species that fills an early gap in the fossil record of tyrannosaurs, revealing how they evolved to become massive apex predators. Researchers analyzing the species' remains have named it Khankhuuluu mongoliensis, which translates to 'dragon prince of Mongolia,' because it was small compared with its much larger relatives such as Tyrannosaurus rex, whose name means 'the tyrant lizard king.' The newly identified dinosaur was the closest known ancestor of tyrannosaurs and likely served as a transitional species from earlier tyrannosauroid species, according to the findings published Wednesday in the journal Nature. Based on a reexamination of two partial skeletons uncovered in Mongolia's Gobi Desert in 1972 and 1973, the new study suggests that three big migrations between Asia and North America led tyrannosauroids to diversify and eventually reach a gargantuan size in the late Cretaceous Period before going extinct 66 million years ago. 'This discovery of Khankhuuluu forced us to look at the tyrannosaur family tree in a very different light,' said study coauthor Darla Zelenitsky, associate professor within the department of Earth, energy, and environment at the University of Calgary, in an email. 'Before this, there was a lot of confusion about who was related to who when it came to tyrannosaur species. What started as the discovery of a new species ended up with us rewriting the family history of tyrannosaurs.' Multiple migrations over millions of years Tyrannosaurs, known scientifically as Eutyrannosaurians, bring to mind hulking dinosaurs like Tyrannosaurus rex and Tarbosaurus, which weighed multiple metric tons and could take down equally large prey. With short arms and massive heads, they walked on two legs and boasted sharp teeth, Zelenitsky said. But tyrannosaurs didn't start out that way. They evolved from smaller dinosaurs before dominating the landscapes of North America and Asia between 85 million and 66 million years ago, the researchers said. While Tarbosaurus, an ancestor of T. rex, clocked in at between 3,000 and 6,000 kilograms (6,613 pounds and 13,227 pounds), the fleet-footed Khankhuuluu mongoliensis likely weighed only around 750 kilograms (1,653 pounds), spanned just 2 meters (6.5 feet) at the hips and 4 meters (13 feet) in length, according to the study authors. Comparing the two dinosaurs would be like putting a horse next to an elephant —Khankhuuluu would have reached T. rex's thigh in height, Zelenitsky said. 'Khankhuuluu was almost a tyrannosaur, but not quite,' Zelenitsky said. 'The snout bone was hollow rather than solid, and the bones around the eye didn't have all the horns and bumps seen in T. rex or other tyrannosaurs.' Khankhuuluu mongoliensis, or a closely related ancestor species, likely migrated from Asia to North America across a land bridge between Alaska and Siberia that connected the continents 85 million years ago, Zelenitsky said. Because of this migrant species, we now know that tyrannosaurs actually evolved first on the North American continent and remained there exclusively over the next several million years, she said. 'As the many tyrannosaur species evolved on the continent, they became larger and larger.' Due to the poor fossil record, it's unclear what transpired in Asia between 80 million to 85 million years ago, she added. While some Khankhuuluu may have remained in Asia, they were likely replaced later on by larger tyrannosaurs 79 million years ago. Meanwhile, another tyrannosaur species crossed the land bridge back to Asia 78 million years ago, resulting in the evolution of two related but very different subgroups of tyrannosaurs, Zelenitsky said. One was a gigantic, deep-snouted species, while the other known as Alioramins was slender and small. These smaller dinosaurs have been dubbed 'Pinocchio rexes' for their long, shallow snouts. Both types of tyrannosaurs were able to live in Asia and not compete with each other because the larger dinosaurs were top predators, while Alioramins were mid-level predators going after smaller prey — think cheetahs or jackals in African ecosystems today, Zelenitsky said. 'Because of their small size, Alioramins were long thought to be primitive tyrannosaurs, but we novelly show Alioramins uniquely evolved smallness as they had 'miniaturized' their bodies within a part of the tyrannosaur family tree that were all otherwise giants,' Zelenitsky said. One more migration happened as tyrannosaurs continued to evolve, and a gigantic tyrannosaur species crossed back into North America 68 million years ago, resulting in Tyrannosaurus rex, Zelenitsky said. 'The success and diversity of tyrannosaurs is thanks to a few migrations between the two continents, starting with Khankhuuluu,' she said. 'Tyrannosaurs were in the right place at the right time. They were able to take advantage of moving between continents, likely encountering open niche spaces, and quickly evolving to become large, efficient killing machines.' Revisiting a decades-old find The new findings support previous research suggesting that Tyrannosaurus rex's direct ancestor originated in Asia and migrated to North America via a land bridge and underscore the importance of Asia in the evolutionary success of the tyrannosaur family, said Cassius Morrison, a doctoral student of paleontology at University College London. Morrison was not involved in the new research. 'The new species provides essential data and information in part of the family tree with few species, helping us to understand the evolutionary transition of tyrannosaurs from small/ medium predators to large apex predators,' Morrison wrote in an email. The study also shows that the Alioramini group, once considered distant relatives, were very close cousins of T. rex. What makes the fossils of the new species so crucial is their age — 20 million years older than T. rex, said Steve Brusatte, professor and personal chair of Palaeontology and Evolution at the University of Edinburgh. Brusatte was not involved in the new study. 'There are so few fossils from this time, and that is why these scientists describe it as 'murky,'' Brusatte said. 'It has been a frustrating gap in the record, like if you suspected something really important happened in your family history at a certain time, like a marriage that started a new branch of the family or immigration to a new country, but you had no records to document it. The tyrannosaur family tree was shaped by migration, just like so many of our human families.' With only fragments of fossils available, it's been difficult to understand the variation of tyrannosaurs as they evolved, said Thomas Carr, associate professor of biology at Carthage College in Wisconsin and director of the Carthage Institute of Paleontology. Carr was not involved in the new research. But the new study sheds light on the dinosaurs' diversity and clarifies which ones existed when — and how they overlapped with one another, he said. More samples from the fossil record will provide additional clarity, but the new work illustrates the importance of reexamining fossils collected earlier. 'We know so much more about tyrannosaurs now,' Carr said. 'A lot of these historical specimens are definitely worth their weight in gold for a second look.' When the fossils were collected half a century ago, they were only briefly described at the time, Brusatte said. 'So many of us in the paleontology community knew that these Mongolian fossils were lurking in museum drawers, waiting to be studied properly, and apt to tell their own important part of the tyrannosaur story,' he said. 'It's almost like there was a non-disclosure agreement surrounding these fossils, and it's now expired, and they can come out and tell their story.'
