Miraxis Hurrya newly discovered dinosaur species with completely disproportionately short arms like T-Rex. Credit: Jorge Gonzalez
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Miraxis Hurry – A new dinosaur species has been discovered with disproportionately short arms, just like T-Rex Telephone call Miraxis Hurry.
Dinosaurs (like the infamous) T-Rex) isn’t the only group of giant carnivorous small-arms dinosaurs. Paleontologists have even discovered a new dinosaur species with completely disproportionately short arms such as: T-Rex Telephone call Miraxis Hurry† The results will be published in the journal current biology Today (July 7) he argued: T-Rex And the M Gigas Developed to have completely independent small arms, it identified many potential functions of short arms, such as mating or assisting locomotion.
‘fossil M Gigas Never seen before, it shows whole parts of the skeleton, such as the arms and legs that helped us understand some of the evolutionary trends and anatomy of Carcharodontosaurids – the group that M Gigas It “belongs to,” said Juan Canal, project leader of the Ernesto Bachmann Museum of Paleontology in Neuquén, Argentina.
First, to make up for it, the authors say that: T-Rex Didn’t get their short arms from M Gigas Or vice versa. Not only M Gigas It went extinct about 20 million years ago T-Rex They became a species, but in the evolutionary tree they are also very far apart. “There is no direct relationship between the two,” Kanal says. Instead, Kanal believes that having small arms provides dinosaurs with some sort of survival advantage in some way.
Miraxis Hurry It is a giant carnivorous dinosaur. Credit: Carlos Papulio
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“I am convinced that those relatively small arms have a function. The skeleton shows large muscular inserts and fully developed pecs, so the arm had strong muscles,” says Kanall. This indicates that the arms did not contract because they were useless to dinosaurs. The more difficult question is what exactly are the functions.
From previous studies, the research group has proved that for dinosaurs such as: M Gigas And the T-RexThe bigger their heads were, the smaller their arms became. They certainly weren’t useful for hunting, as “actions associated with predation were most likely done by the head,” Kanall argues.
“I tend to think that their arms were used for other types of activities,” Kanal says. From the fossil record, the team was able to paint a picture of this life M Gigas before you die. The dinosaur lived in the region of present-day Northern Patagonia in Argentina and was 45 years old, about 11 meters long and weighed more than four tons. And she had a big family. “The group thrived and peaked in diversity shortly before its extinction,” Kanal says. “They may have used the arms for reproductive behavior, such as holding the female during mating or supporting themselves to recline after a break or a fall,” Kanall added.
excavation site Miraxis Hurry† Credit: Juan I Canal
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The team also found that a skull M Gigas They were decorated with combs, grooves, spurs and small horns. “These motifs appear late in development as individuals mature,” Kanal says. The group believes the features may have been used to attract potential partners. “Sexual selection is a powerful evolutionary force. But because we can’t directly observe their behavior, it’s impossible to be sure,” Kanall said.
“The fossil contains a lot of new information and it is in excellent condition,” Kanall said. He looks forward to exploring other questions he asks M Gigas Fossil can help him answer. “We found the perfect place on the first day of searching, and M Gigas “It was probably one of the most exciting points in my career,” Kanall says.
Reference: “New Giant Carnivorous Dinosaur Reveals Converging Evolutionary Trends in Theropod Arm Reduction” by Juan I Canal, Sebastian Apisteguia, Pablo A. Galena, Jonathan Mitchell, Nathan D. Smith, Thomas M. Colin, Akiko Shinya, Alejandro Halusa, Federico Giancini , Peter J. Makovsky, July 7, 2022, Available here. current biology.
DOI: 10.1016/j.cub.2022.05.057
This work was supported by the United States National Science Foundation and the National Geographic Society.
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