Grand-Staircase Escalante’s new findings indicate that tyrannosaurs may have hunted, lived in groups – St George News

SF. GEORGE – In popular media such as “Jurassic Park”, “The Land Before Time” and “King Kong”, large carnivorous dinosaurs such as Tyrannosaurus rex are always described as solitary and highly competitive hunters. As scary as it is to imagine even one of those titanic meat eaters chasing you like prey, it’s even more awful to consider trying to get rid of many of them at once. However, recent research suggests that may have been the case.

In 2014, paleontologists working on the Grand Scara-Escalante National Monument found a series of fossils that included four specimens of tyrannosaurs. Over the next seven years, the research team carefully excavated and studied numerous fossils led by Dr. Alan Titus, a paleontologist in the Office of Land Management.

At a news conference Monday morning, Titus and some of his colleagues are studying Teratofon it remains to be seen that at least some of these ancient carnivores were social and could have lived and hunted in groups.

“I’ve talked to many researchers in tyrannosaurs, and one couple in particular insists that these animals simply didn’t have the brain power to engage in sophisticated social interaction,” Titus said. “With tyrannosaurs, you look at a unique line of predatory dinosaurs called Coelurosauria.”

Titus said that one of the key features of Coelurosauria is the enlarged brain.

“They actually have a larger cranial volume than their opponents or ancestors,” he said. “We interpret this as opening the door to increased computing power, if you will, in the brain and the evolution of social behaviors.”

We might wonder why such a large and powerful predator would need help in a hunt. A contributing researcher, Dr. Joseph Sertich at the Denver Museum of Nature and Science, said social behavior could have helped dinosaurs hunt larger prey and reduce individual risk.

“The same stones that bury this Teratofon the group also includes amazing horned dinosaurs such as Kosmoceratops and Utahceratops and very large hadrosaurs such as Gryposaurus and Crested Parasaurolophus, “said Sertich.” Being in a social unit, these tyrannosaurs could have had a more likely to take over some of these really big or really dangerous herbivores. ”

Revealing the mystery

The Grand Staircase-Escalante National Monument project became an international research effort, and the research team published its findings in the peer-open scientific journal PeerJ.

The fossils at the site were discovered, cleaned and examined by BLM paleontologists, including Titus and laboratory manager Katja Knoll. A thorough investigation has shown that the fossils come from many individual tyrannosaurs of varying age and size, as well as other prehistoric fauna, such as ancient turtles, fish and an almost complete area. Deinosuc skeleton.

“One of these things is definitely not like the others and it would be tyrannosaurs,” Titus said. “How did these tyrannosaurs end up in a lake?” This became the first mystery we had to solve. ”

Analyzing the soil at the excavation site and comparing it to the minerals and rocks trapped in the fossils, the researchers concluded that the dinosaurs were not initially buried at that level and could have been re-buried after environmental changes.

This led researchers to question whether the remains of the tyrannosaurus simply gathered in the riverbed over time, which would not substantiate any theory about their social behavior, Titus said.

Dr. Celina Suarez of the University of Arkansas, along with Dr. Daigo Yamamura, did a geochemical analysis of all the fossils to compare them and see if they differed in key ways.

“We can look at the diet, the temperature and even the type of water or the isotopic composition of the water that different animals drink,” Suarez said. „The Teratofon, fish, turtles, crocodilians and carbonate nodules (rock samples from the same soil layer) have very similar patterns of rare earth elements, suggesting that they all died and were fossilized together. ”

Using these geochemical tools, the fossils were also dated to about 76 million years ago. Now that they knew the fossils belonged together and were not misleading, researchers were determined to ask what could have brought them together.

Titus said that the remains and the apparent cause of death – the floods – were remarkably similar to the oldest evidence found and perhaps best known to social tyrannosaurs.

In the late 1990s, Canadian paleontologist Dr. Phil Currie began excavating the Dry Island Buffalo Jump in Alberta. There he discovered the remains of at least 12 tyrannosaurs of different ages who appeared to have been killed in another mass event. He theorized that the discovery was evidence of social behavior, although it was directly opposed to popular scientific theory, Titus said.

The discovery at the Grand Staircase-Escalante National Monument is the first of its kind in the southwestern United States, but it adds to a growing body of evidence that seems to validate Dr. Currie’s earlier hypothesis. Tyrannosaurs could have been smarter and more social than previously thought.

Understanding the research site

The fossils were discovered in the Kaiparowits subunit of the national monument, in a site now known as the “Rainbow and Unicorn Career”. Titus said the name appeared during a telephone conversation between two of his colleagues.

“A former employee of mine … thought I was a little too excited about every fossil site I’ve ever found.”

Titus said that colleagues jokingly accused him many times of claiming that every site, including the Grand Scara-Escalante National Monument, is “rainbows and unicorns all the time.”

However, in this case, Titus’ colleagues agreed that the site of the monument is indeed as good as it looked.

“So the name just came out.”

The researchers even brought a stuffed, unicorn, rainbow-colored toy to the dig site as a mascot.

Interior Secretary Deb Haaland recently visited the Grand-Staircase Escalante National Monument, where he and Titus visited and handled some of the fossils. Although the Biden administration has not taken any official action to restore Utah’s national monuments to their pre-Trump size, the president has frequently promised the same during his 2020 campaign.

The Rainbows and Unicorns site remains within the boundaries of the diminished monument, but some conservatives fear that many such sites are outside the current boundaries and may be vulnerable to exploitation or unintentional destruction.

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