Discovery of new Tyrannosaurus species through early fossil findings

A portion of a dinosaur skull discovered 40 years ago has been identified as a new species of dinosaur. tyrannosaurusand is probably the closest relative tyrannosaurus rex. The study adds a new twist to the long-standing debate about how many different tyrannosaurus species there were, and could help shed light on how the iconic predator evolved.

tyrannosaurus They first appeared in North America about 68 million years ago, 2 million years before the mass extinction event that wiped out most dinosaurs. Paleontologists are puzzled about the origins of this carnivore. Some suggest that it is an ancestor of tyrannosaurus Some people walked across land bridges from prehistoric Asia, while others traced their origins to southern North America.

Anthony Fiorillo Researchers from the New Mexico Museum of Natural History and Science reviewed fossils in the museum's collection that were discovered in a rock formation known as the McRae Formation in western New Mexico.

Skulls were originally classified as: tyrannosaurus, Fiorillo and his colleagues noticed differences in the bones.They proposed that this specimen represented an older species, which they named Tyrannosaurus macraiensis in reference to the rock in which it was found.

They estimated that the dinosaur was about 12 meters long, comparable in size to an aosaurus. Tyrannosaurus, However, it lived about 4 million years ago.

difference between tyrannosaurus and T. macraensis It would have been relatively subtle.on the other hand tyrannosaurus He had a prominent ridge on his eyebrow, and a bone-crushingly wide jaw with the same ridge. T. macraensis The body is less developed and the skull is thinner, Fiorillo said.

Other recent studies have proposed that several species exist. tyrannosaurus And the so-called tyrannosaurus Fossils need to be reallocated. However, such proposals are controversial and are mostly rejected by dinosaur paleontologists. The new study is likely to spark further debate about that number. tyrannosaurus The species was found in North America.

“I hesitate to consider Tyrannosaurus macraiensis as different from tyrannosaurus rex” Jared Voris at the University of Calgary, Canada. He points out that many of the anatomical features that make the new species unique are also present in the specimen. tyrannosaurus.

Regardless of species assignment, the existence of such large tyrannosaurs millions of years ago is tyrannosaurus This suggests that southwestern North America was an important center of dinosaur evolution. “The age range of the proposed specimen is unique and requires further study,” Voris said. That's because it could outline a clearer picture of dinosaur evolution during the last few million years of the Cretaceous.

The New Mexico tyrannosaurus was discovered in the same rock as a giant horned dinosaur, an anthropomorphic duck-billed dinosaur, and a long-necked herbivore up to 30 meters long. Fiorillo and his colleagues tyrannosaurus It may have evolved to its gigantic size to prey on these large herbivores, and later spread north as the last “tyrant lizard” to stalk the planet.