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Scientists have identified dinosaur species that were unknown before closing the early gaps in the Tyrannosaurus fossil record, revealing how they evolved to become large-scale apex predators.
Researchers analyzing the species were named Cankful Mongoliensis, translated into “The Mongolian Dragon Prince.” Because it is smaller than much larger relatives such as the Tyrannosaurus Rex, which means “Tyrant Lizard King.” The newly identified dinosaur is the closest known ancestor of the Tyrannosaurus, and perhaps it may have served as a transitional species of early Tyrannosauroid species, according to findings published Wednesday in Nature Journal.
Based on a reexamination of two partial skeletal structures discovered in the Gobi Desert, Mongolia in 1972 and 1973, new research suggests that three major migrations between Asia and North America diversified tyrannosauroids in the late Cretaceous before their extinction 660,000 years ago, and ultimately reached Cretaceous Gargantoansize.
“This discovery of Cancful Darla Zelenitsky, an associate professor at the Department of Earth, Energy and Environment at the University of Calgary, has had a lot of confusion about who was involved when he came to Tyrannosaurus. What began as a discovery of a new species led to a rewrite of the family history of the Tyrannosaurus. ”
Scientifically known as the Utyrannosaurus, Tyrannosaurus reminds us of giant dinosaurs like the Tyrannosaurus Rex and the Turbosaurus.
With their arms and huge heads, they boasted sharp teeth walking on two legs, Zelenitsky said.
But Tyrannosaurs didn’t begin that way. They evolved from small dinosaurs before they ruled North American and Asian landscapes 85 to 66 million years ago, researchers said.
T. Rex’s ancestor, Tarbosaurus, was recorded between 3,000 and 6,000 kilograms (6,613 pounds and 13,227 pounds), while the fleet-footed Khankhuulu Mongoliensis weighed only about 750 kilograms (1,653 pounds). According to the research authors.
I think comparing two dinosaurs is like placing a horse next to an elephant. Cankfulu had reached height on T. rex’s thighs, Zelenitsky said.
“Cankfru was mostly a tyrannosaurus, but it wasn’t perfect,” Zelenitsky said. “The nose bones were not solid, but hollows, and the bones around the eyes didn’t have all the horns and bumps found in T. Rex and other tyrannosaurus.”
Khankhuulu Mongoliensis, or a closely related ancestor species, likely migrated from Asia to North America 85 million years ago, across the overpass between Alaska and Siberia that connect the continents.
Because of this immigrant species, we now know that Tyrannosaurus actually first evolved on the North American continent and remained there exclusively for millions of years to come, she said. “As many tyrannosaurus species evolved on the continent, they became bigger.”
She added that it is unclear what happened in Asia between 80 and 85 million years ago due to poor fossil records. Some Cankful may have remained in Asia, but it is possible that it was replaced by a massive tyrannosaurus 79 million years ago.
Meanwhile, another Tyrannosaurus species returned to Asia 78 million years ago, over the overpass, resulting in two related but very different subgroups of tyrannosaurus evolved, Zelenitsky said. One was a huge, deepened species, and the other was a species known as aryolamine. These small dinosaurs are called “Pinocchiorex” because of their long, shallow nose.
Both types of tyrannosaurus can live in Asia, as the larger dinosaurs are the best predators, and they did not compete with each other, but Ariolamin chasing smaller prey.
“Their small size meant that Ariolamin was long thought to be a primitive tyrannosaurus, but we have “small down” our bodies within a part of the Tyrannosaurus family tree, which was otherwise a giant, indicating a new, small nature that Ariolamin evolved naturally,” Zelenitsky said.
Another migration occurred as the Tyrannosaurus continued to evolve, and 68 million years ago, the giant Tyrannosaurus species returned to North America and then to Tyrannosaurus Rex, Zelenitsky said.
“The success and diversity of Tyrannosaurs is thanks to several migrations between the two continents starting with Khankhuuluu,” she said. “The Tyrannosaurs were in the right place at the right time. They took advantage of traveling between continents, possibly encountering open niche spaces, and quickly evolved into a large, efficient killing machine.”
The new findings support previous research suggesting that Tyrannosaurus Rex’s direct ancestors originated from Asia and migrated to North America via land bridges, highlighting the importance of Asia in the evolutionary success of the Tyrannosaurus family, said Cassius Morrison, a doctoral student in paleontology at the University of London. Morrison was not involved in the new research.
“The new species provide essential data and information for some of the family trees with most species, and helps us understand the evolutionary transition of tyrannosaurus from small/medium predators to large apex predators,” Morrison wrote in an email.
The study also shows that the Alioramini group, once considered a distant relative, was a very close cousin of T. Rex.
Steve Bursatte, professor and personal chair of paleontology and evolution at the University of Edinburgh, describes new fossils as a very important age. Brusatte was not involved in the new research.
“There are so few fossils from this point onwards, so these scientists describe it as “muddy,” Brusatte said. “It was an annoying gap in the records, as if something really important happened in the history of a family, like a marriage that began to immigrate to a new country, but there was no record to document it.
As fossil fragments are only available, it has been difficult to understand the variations of tyrannosaurus as tyrannosaurus evolved, said Thomas Kerr, an associate professor of biology at the University of Carthage in Wisconsin and director of the Institute of Paleontology in Carthage. Kerr was not involved in the new research. But new research shed light on dinosaur diversity, clarifying when it existed and how they overlapped with each other, he said.
While more samples become clearer from the fossil record, the new work demonstrates the importance of reexamining previously collected fossils.
“We know more about Tyrannosaurus now,” Kerr said. “Many of these historical specimens are worth the weight of gold in their second view.”
When the fossils were collected half a century ago, they were briefly explained at the time, Brusatte said.
“Many of us in the paleontological community knew that these Mongol fossils were hiding in the drawers of the museum, waiting to properly study, and tended to convey a unique and important part of the Tyrannosaurus story,” he said. “This appears to have been a non-disclosure agreement surrounding these fossils, and now it’s expired and they can come out and tell the story.”