66 million years ago, Tyrannosaurus rex were comfortably settled at the top of the food chain. At least in the emerged lands. Undoubtedly, its 12 meters long, its 8 tons of weight and its sharp teeth of between 20 and 30 centimeters contributed to this . And, although some paleontologists maintain that these animals were, above all, scavengers, experts tend to consider them the greatest hunters of their time.
Now, an international team of researchers from different institutions has determined that these theropods developed to their colossal size in much less time than had been suspected until now. This is reflected in a study published in the journal Proceedings of the National Academy of Sciences . In it, these scientists, coordinated by the evolutionary biologist Stephen L. Brusatte, from the Faculty of Geosciences at the University of Edinburgh, reveal that the remains of a new horse-sized tyrannosaurid, called Timurlengia euotica , have revealed how the T. rex and its closest relatives became great super predators .
Among paleontologists, the most widespread hypothesis to date held that Tyrannosaurus rex evolved from smaller species during a process that spanned 70 million years . However, the findings of Brusatte and his colleagues suggest that much of this transition occurred very quickly, in the final stages of that process.
His work also shows that before acquiring their large size, tyrannosaurs developed certain cognitive abilities and fine-tuned senses that, among other things, allowed them, for example, to hear low-frequency sounds and perceive vibrations at great distances .
These evolutionary advantages led T. rex to fill the gap left in ecosystems by other large predators, which disappeared some 80 million years ago. “Tyrannosaurs had to get smart before they got really big,” says Brusatte.
The Timurlengia euotica now described by these paleontologists lived about 90 million years ago in what is now Uzbekistan , filling a 20 million-year gap in the tyrannosaurus fossil record. According to Hans-Dieter Sues, from the Department of Paleobiology at the National Museum of Natural History, in the USA, who participated in the study, “he was an agile hunter; it chased its prey and had razor-sharp teeth , specially developed to cut meat. “
The study of the skull of this dinosaur using computed tomography has allowed to recreate the structure of its brain. In this way, it has been possible to know that the ancestors of the T. rex probably closely resembled the Timurlengia euotica , although, yes, they had a larger skull .
Image: Todd Marshall
