Latest news with #BeringStrait
Yahoo
10-05-2025
- Science
- Yahoo
Where Did the T. rex Come From? Paleontologists Think They've Finally Figured It Out
Fossils of the T. rex, tyrant lizard and queen of the dinosaurs, are found exclusively in North America. Strangely, they have more in common with other large theropod dinosaurs in Asia than they do with their predatory peers in the United States and Canada. A new study published in the journal Royal Society Open Science may have finally figured out why that is. Analyzing the fossils and evolutionary history of T. rex and related dinosaur groups, paleontologists suggest that T. rex (prehistoric star of Universal's Jurassic Park and Jurassic World films) originated in North America but descended from ancestors which migrated from Asia about 70 million years ago. Paleontologists debate over whether the direct ancestors of Tyrannosaurs came from North America or Asia. A new study led by University College London Ph.D student Cassius Morrison may have answered the question once and for all. 'Our modelling suggests the 'grandparents' of T. rex likely came to North America from Asia, crossing the Bering Strait between what is now Siberia and Alaska,' explained researcher Cassius Morrison, via the Natural History Museum, London. 'This is in line with past research finding that the T. rex was more closely related to its Asian cousins than to North American relatives such as Daspletosaurus. Our findings indicate that, while dozens of T. rex fossils have been unearthed in North America, the fossils of its direct ancestor may lie undiscovered still in Asia.' The world 90 million years ago looked a little bit different. If you go back about 250 million years ago, all the world's land masses were gathered together in the supercontinent Pangaea. It began to break up about 200 million years ago, separating into the ancient continents of Laurasia in the north and Gondwanaland in the south. By the time we reached the Cretaceous (144 - 66 million years ago), the modern continents had separated but were still squished together tightly. North America was separated into two continents, Laramidia in the west and Appalachia in the east, separated by the Western Interior Seaway. Travel between the land masses was a little easier then than it is now. Those long-extinct ancestors of Tyrannosaurs were significantly smaller than their more famous descendants. Some were roughly equivalent to a medium-sized dog while others were small enough to sit comfortably on your shoulders. They first started getting big about 90 million years ago, when the large-statured carcharodontosaurid theropods went extinct. Exploiting a vacant niche, Tyrannosaurs evolved from their diminutive ancestors to become apex predators of the Late Cretaceous. Around the same time the carcharodontosaurids were going extinct, the planet was going through a period of rapid cooling. The world reached a peak in global temperatures known as the Cretaceous Thermal Maximum about 92 million years ago, then temperatures dropped. Tyrannosaurids and a related group of large predators known as the megaraptors survived because they were better equipped for colder temperatures and grew to gigantic sizes to fill the empty niche. 'Our findings have shined a light on how the largest tyrannosaurs appeared in North and South America during the Cretaceous and how and why they grew so large by the end of the age of dinosaurs,' said Charlie Scherer, also from University College London, via Sci News. However Rexy got here, we're just glad she did, cause she makes for great entertainment! Catch Jurassic World Dominion, , and for Jurassic World Rebirth, in theaters July 2.
CNN
06-05-2025
- Science
- CNN
T. rex ancestors crossed from Asia to North America via land bridge 70 million years ago, says study
Sign up for CNN's Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. CNN — The direct ancestor of Tyrannosaurus rex would have arrived in North America after crossing a land bridge from Asia, according to a new study. The report is the latest to weigh in on the fierce debate among paleontologists over the origins of the king of the dinosaurs. A team led by Cassius Morrison, a doctoral student of paleontology at University College London, or UCL, used mathematical modeling to conclude that T. rex precursors likely arrived in North America after crossing the Bering Strait between modern-day Siberia and Alaska around 70 million years ago. The finding tracks with past research that suggests T. rex was more closely related to the large carnivore Tarbosaurus in Asia compared with top predators in North America such as Daspletosaurus, Morrison said in a statement. At the time, the area would have been home to temperate rainforests, with a climate somewhat similar to British Columbia today, Morrison told CNN on Tuesday. T. rex ancestors — tyrannosaurids — would have been fewer in number within their environment compared with the herbivorous dinosaurs they preyed on, much like apex predators such as lions are today, Morrison said. 'And because they are fewer, there are also fewer chances for them to then be preserved in the fossil record,' he said. Faced by this lack of evidence, Morrison and his coauthors instead used mathematical models that incorporate data from the existing fossil record and the T. rex family tree, as well as climatic and environmental conditions, Morrison said. The modeling also accounts for gaps in the fossil record, meaning that it can be updated if new discoveries are made in future research, he added. For example, Morrison said the new study's findings suggest fossils of these T. rex ancestors may still remain undiscovered in Asia. The team also found that tyrannosaurids such as T. rex experienced a rapid increase in size during a period in which global temperatures were falling, suggesting that these dinosaurs were better able to thrive in cooler climates, perhaps thanks to their feathers or the fact that they were more warm-blooded. The rapid growth in size also came after another group of giant meat-eating dinosaurs known as carcharodontosaurids went extinct, leaving 'a vacuum at the top of the food chain,' according to a news release from UCL on Tuesday. This growth meant that, by the time dinosaurs went extinct, T. rex could have weighed as much as 9 metric tons, 'about the same as a very large African elephant or a light tank,' according to the release. Related article Hiking family discovers rare T. rex fossil Study coauthor Charlie Scherer, a master's graduate in Earth sciences and soon-to-be doctoral student at UCL, said in a statement that the 'findings have shined a light on how the largest tyrannosaurs appeared in North and South America during the Cretaceous (Period) and how and why they grew so large by the end of the age of dinosaurs.' 'They likely grew to such gigantic sizes to replace the equally giant carcharodontosaurid theropods that went extinct about 90 million years ago,' Scherer said. 'This extinction likely removed the ecological barrier that prevented tyrannosaurs from growing to such sizes.' Steve Brusatte, a paleontologist at the University of Edinburgh in Scotland who was not involved in the study, told CNN that the paper 'is fine scholarly work that forensically tracks tyrannosaurs and other meat-eating dinosaurs over time, and compares their evolution with changes in climate. 'Even the very largest and most dominant dinosaurs were affected by the weather. It seems like tyrannosaurs were able to get big multiple times independently, when cooler climates promoted increases in size,' he said. 'It was easier to be big when temperatures were cool. The kings of the dinosaurs were not predestined to rule, but were helped along by the climate,' Brusatte added. The study was published in the journal Royal Society Open Science.
CNN
06-05-2025
- Science
- CNN
T. rex ancestors crossed from Asia to North America via land bridge 70 million years ago, study finds
Sign up for CNN's Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. The direct ancestors of Tyrannosaurus rex would have arrived in North America after crossing a land bridge from Asia, according to a new study. The report is the latest to weigh in on the fierce debate among paleontologists over the origins of the king of the dinosaurs. A team led by Cassius Morrison, a doctoral student of paleontology at University College London, or UCL, used mathematical modeling to conclude that T. rex precursors likely arrived in North America after crossing the Bering Strait between modern-day Siberia and Alaska around 70 million years ago. The finding tracks with past research that suggests T. rex was more closely related to the large carnivore Tarbosaurus in Asia compared with top predators in North America such as Daspletosaurus, Morrison said in a statement. At the time, the area would have been home to temperate rainforests, with a climate somewhat similar to British Columbia today, Morrison told CNN on Tuesday. T. rex ancestors — tyrannosaurids — would have been fewer in number within their environment compared with the herbivorous dinosaurs they preyed on, much like apex predators such as lions are today, Morrison said. 'And because they are fewer, there are also fewer chances for them to then be preserved in the fossil record,' he said. Faced by this lack of evidence, Morrison and his coauthors instead used mathematical models that incorporate data from the existing fossil record and the T. rex family tree, as well as climatic and environmental conditions, Morrison said. The modeling also accounts for gaps in the fossil record, meaning that it can be updated if new discoveries are made in future research, he added. For example, Morrison said the new study's findings suggest fossils of these T. rex ancestors may still remain undiscovered in Asia. The team also found that tyrannosaurids such as T. rex experienced a rapid increase in size during a period in which global temperatures were falling, suggesting that these dinosaurs were better able to thrive in cooler climates, perhaps thanks to their feathers or the fact that they were more warm-blooded. The rapid growth in size also came after another group of giant meat-eating dinosaurs known as carcharodontosaurids went extinct, leaving 'a vacuum at the top of the food chain,' according to a news release from UCL on Tuesday. This growth meant that, by the time dinosaurs went extinct, T. rex could have weighed as much as 9 metric tons, 'about the same as a very large African elephant or a light tank,' according to the release. Study coauthor Charlie Scherer, a master's graduate in Earth sciences and soon-to-be doctoral student at UCL, said in a statement that the 'findings have shined a light on how the largest tyrannosaurs appeared in North and South America during the Cretaceous (Period) and how and why they grew so large by the end of the age of dinosaurs.' 'They likely grew to such gigantic sizes to replace the equally giant carcharodontosaurid theropods that went extinct about 90 million years ago,' Scherer said. 'This extinction likely removed the ecological barrier that prevented tyrannosaurs from growing to such sizes.' Steve Brusatte, a paleontologist at the University of Edinburgh in Scotland who was not involved in the study, told CNN that the paper 'is fine scholarly work that forensically tracks tyrannosaurs and other meat-eating dinosaurs over time, and compares their evolution with changes in climate. 'Even the very largest and most dominant dinosaurs were affected by the weather. It seems like tyrannosaurs were able to get big multiple times independently, when cooler climates promoted increases in size,' he said. 'It was easier to be big when temperatures were cool. The kings of the dinosaurs were not predestined to rule, but were helped along by the climate,' Brusatte added. The study was published in the journal Royal Society Open Science.
CNN
06-05-2025
- Science
- CNN
T. rex ancestors crossed from Asia to North America via land bridge 70 million years ago, says study
Sign up for CNN's Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. CNN — The direct ancestors of Tyrannosaurus rex would have arrived in North America after crossing a land bridge from Asia, according to a new study. The report is the latest to weigh in on the fierce debate among paleontologists over the origins of the king of the dinosaurs. A team led by Cassius Morrison, a doctoral student of paleontology at University College London, or UCL, used mathematical modeling to conclude that T. rex precursors likely arrived in North America after crossing the Bering Strait between modern-day Siberia and Alaska around 70 million years ago. The finding tracks with past research that suggests T. rex was more closely related to the large carnivore Tarbosaurus in Asia compared with top predators in North America such as Daspletosaurus, Morrison said in a statement. At the time, the area would have been home to temperate rainforests, with a climate somewhat similar to British Columbia today, Morrison told CNN on Tuesday. T. rex ancestors — tyrannosaurids — would have been fewer in number within their environment compared with the herbivorous dinosaurs they preyed on, much like apex predators such as lions are today, Morrison said. 'And because they are fewer, there are also fewer chances for them to then be preserved in the fossil record,' he said. Faced by this lack of evidence, Morrison and his coauthors instead used mathematical models that incorporate data from the existing fossil record and the T. rex family tree, as well as climatic and environmental conditions, Morrison said. The modeling also accounts for gaps in the fossil record, meaning that it can be updated if new discoveries are made in future research, he added. For example, Morrison said the new study's findings suggest fossils of these T. rex ancestors may still remain undiscovered in Asia. The team also found that tyrannosaurids such as T. rex experienced a rapid increase in size during a period in which global temperatures were falling, suggesting that these dinosaurs were better able to thrive in cooler climates, perhaps thanks to their feathers or the fact that they were more warm-blooded. The rapid growth in size also came after another group of giant meat-eating dinosaurs known as carcharodontosaurids went extinct, leaving 'a vacuum at the top of the food chain,' according to a news release from UCL on Tuesday. This growth meant that, by the time dinosaurs went extinct, T. rex could have weighed as much as 9 metric tons, 'about the same as a very large African elephant or a light tank,' according to the release. Related article Hiking family discovers rare T. rex fossil Study coauthor Charlie Scherer, a master's graduate in Earth sciences and soon-to-be doctoral student at UCL, said in a statement that the 'findings have shined a light on how the largest tyrannosaurs appeared in North and South America during the Cretaceous (Period) and how and why they grew so large by the end of the age of dinosaurs.' 'They likely grew to such gigantic sizes to replace the equally giant carcharodontosaurid theropods that went extinct about 90 million years ago,' Scherer said. 'This extinction likely removed the ecological barrier that prevented tyrannosaurs from growing to such sizes.' Steve Brusatte, a paleontologist at the University of Edinburgh in Scotland who was not involved in the study, told CNN that the paper 'is fine scholarly work that forensically tracks tyrannosaurs and other meat-eating dinosaurs over time, and compares their evolution with changes in climate. 'Even the very largest and most dominant dinosaurs were affected by the weather. It seems like tyrannosaurs were able to get big multiple times independently, when cooler climates promoted increases in size,' he said. 'It was easier to be big when temperatures were cool. The kings of the dinosaurs were not predestined to rule, but were helped along by the climate,' Brusatte added. The study was published in the journal Royal Society Open Science.
