A recently discovered relative Tyrannosaurus rex stood just over a meter in the hips, shows research.
A miniature tyrannosaur opens up important new information on how T. Rex has proven to be the dominant predator in North America.
At the beginning of their evolution, the tyrannosaurs were small, but at a certain stage awkward T. Rex along with others, appeared as apical predators.
The new fossil helps fill the 70 million years of fossil fissures.
The Tyrannosaurus, or the "tyrant of the lizard" ̵
But, as co-authored by Lindsey Zanno of the State University of North Carolina, this was not always the case: "Early in their evolution," the Thyranosavruses hunted in the shadow of archaic lines, such as the allosaurs that were already installed at the top of the food chain " she said.
Our understanding of the evolutionary events that led to the emergence of giant tyrannosaurs was limited by the absence of complete scams in North America.
Malis, primitive tyrannosaurs were found in North America from the Jurassic period (about 150 million years ago ) About 81 million years ago, North American Tyrannosaurs became huge beasts. But the remains of fossils between these two periods of time are heterogeneous.
Balds of the legs of a new species, Moros intrepidus, were discovered in the same area where Dr. Zanno and her team previously found Siats meekerorum the giant monster dinosaur belonging to to a group known as carcharodontosaurs. This larger predator lived in the same period as Moros . Researchers believe that Moros intrepidus was the size of a modern mule deer, weighing about 78 kg. They were seven years old when she died and almost completely grown.
Although she was relatively light, she was probably very fast on her legs. "These adaptations, along with advanced sensory capabilities, are a sign of a terrible predator, which can easily spoil spoilage, avoiding confrontations with the leading predators of that day," Dr. Zanno said.
Tyrannosaurs were small, their predatory specialisms meant that they were primed to take advantage of new opportunities when the pace of warming, rising sea levels, and reducing the scale of the restructured ecosystem at the beginning of the late Cretaceous.
more than 15 million years to rise to power. "
A scientific article published in the journal Communications Biology suggests that these changes in the environment could lead to the decline of the alosavers – apical predators prevailing before the appearance of big tyrannosaurs.
Analysis of Moros's place in the genus of tyrannosaurs seems to indicate that the group migrated to North America from Asia.
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