discovery of Tyrannosaurus macraiensissister species of the famous one tyrannosaurus rexsuggests that tyrannosaurid dinosaurs originated from Laramidia, an island continent that existed between 100 million and 66 million years ago and stretched from present-day Alaska to Mexico.
“Tyrannosaur dinosaurs were the dominant predators of North America and Asia during the Late Cretaceous period,” said Dr. Sebastian Dalman of the New Mexico Museum of Natural History and Science and his colleagues.
“Evolved from a diminutive ancestor in the mid-Cretaceous period, became an apex predator in the late Cretaceous period, and eventually tyrannosaurus”
“tyrannosaurusWith a sturdy skeleton and powerful bone-crushing jaws, this animal was the dominant carnivore of the late Maastrichtian period in western North America. ”
“Grows up to 12 meters long and weighs 10 tons, tyrannosaurus It was the largest terrestrial predator of its time, and perhaps of all time. ”
“where and when Tyrannosaurini (tyrannosaurus and relatives) origin remains unknown. Competing hypotheses place its origin in Asia or western North America (Laramidia). ”
The newly identified species is Tyrannosaurus McClainlived in what is now the United States 71 million to 73 million years ago, or 5 million to 7 million years ago. tyrannosaurus.
The fossilized partial skull of this dinosaur was discovered in the Hall Lake Formation in New Mexico.
Although the specimens were initially assigned; tyrannosaurus and its size is tyrannosaurusPaleontologists have proposed that the specimen belongs to a new species, due to several subtle differences in the shape and joints between the specimen and the skull. tyrannosaurus.
Analysis of the relationship between Tyrannosaurus McClain and other theropod dinosaur species. Tyrannosaurus McClain It may have been a sister species of tyrannosaurusmaking it the closest known relative. tyrannosaurus.
The authors suggest that Tyrannosaurini may have originated in southern Laramidia, an island continent that existed between 100 million and 66 million years ago and stretched from present-day Alaska to Mexico.
Additionally, Tyrannosaurus, along with other giant dinosaurs of southern Laramidia such as ceratopsians, hadrosaurs and titanosaurs, may have evolved to large body sizes by about 72 million years ago, the researchers say. is suggesting.
They speculate that the evolution of giant tyrannosaurines may have been driven by the enormous body size of the herbivores they preyed on in southern Laramidia.
“The evolution of giant tyrannosaurs in southern North America suggests that large dinosaurs evolved at lower latitudes in North America, along with giant ceratopsians, hadrosaurs, and titanosaurs.” said.
of study It was published in the magazine scientific report.
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SG Dalman other. 2023. Giant tyrannosaurs that lived in southern North America from the Campanian to the Maastrichtian and the evolution of giant tyrannosaurids. science officer 13, 22124; doi: 10.1038/s41598-023-47011-0
Source: www.sci.news
