A new study has analyzed the fossils’ teeth and femurs and found enough differences to split the T-rex into three species – but the thesis divides scientists.
The famous tyrannosaurus rex he may, after all, have belonged to a dynasty with more than one species.
According to a new study published in Evolutionary Biology, this well-known dinosaur divided into three species — T Rex, Imperator Tyrannosaurus and tyrannosaurus regina.
Since the 1990s, the increase in T-Rex fossil discoveries has allowed scientists to discover more information about these animals, which opens the door to the possibility of finding out if these dinosaurs belong to a single species.
To answer this question, the team behind the study analyzed the fossils of 38 T-rexwith particular emphasis on the number of front teeth in the lower jaw and the corpulence of the thigh bones, notes the new scientist.
Experts have found a variation in these two characteristics, thus estimating that this dinosaur is divided into three distinct species. T. imperator was distinguished by its four small incisors and strong thighs from a larger, heavier dinosaur.
This species then evolved until the appearance of two other younger species. T. regina had thinner thigh bones and was smaller while T. rex had sturdier thighs and was heavier.
The authors believe that modern ecosystems show us that predators evolve and they are divided into separate species, so it is likely that this was also the case with tyrannosaurs.
These results have implications for the most famous tyrannosaur fossils, such as Sue, which happens to be a T. imperator, and Stan to be classified as a T. regina.
The study is already dividing the scientific community, with some scientists welcoming the hypothesis, such as Philip Currie, who describes as “incredible” the thesis that “the anatomical changes of the species seem to change over time”.
Stephen Brusatte belongs to the group of skeptical scientists. “I see the temptation to split T. rex into different species, because there is some variation in the bones of the fossils we have. But lately, for me, this variation is very small. Until I see stronger evidence, they’re still all T. rex to me.”
Critics of the new study point to another problem in addition to the lack of hard evidence, noting that the researchers included data from fossils belonging to the Black Hills Geological Research Institute, a private company in South Dakota.
Scientists argue that the studies are due to limits to the analysis of fossils in public collectionsbecause these copies will always be available for scientific study.