Scientists have discovered why the Tyrannosaurus rex had such a powerful jaw. The difference lies in the muscle structure and the lower jaw joint.
If you’ve ever had the chance to stand in front of a complete fossil of the Tyrannosaurus rex (T-rex), you undoubtedly cannot deny the fact that it was the dominant predator during its glorious days.
Adult T-rexes were enormous, with massive skulls and teeth as big as bananas.
Numerous scientific studies have sought to understand the bite force of an adult T-rex. Nevertheless, many mysteries remain regarding how these dinosaurs developed such powerful bites that helped them become the dominant species at the end of the dinosaur era.
The Tyrannosaurus rex emerged about 68 million years ago.
Recently, scientists finally uncovered the reason behind the T-rex’s formidable jaw strength. It turns out that this strength originates from a boomerang-shaped bone located in the lower jaw within the dinosaur’s facial structure.
Unlike mammals, reptiles and their close relatives have a joint in their lower jawbone, known as the intramandibular joint (IMJ).
Based on computer simulations, scientists stated that with a bone extending from the IMJ, the Tyrannosaurus could generate a bite force greater than 6 tons, equivalent to the weight of an adult African elephant.
With such a bite force, the T-rex could easily crush the bones of its prey, making it nearly impossible for the prey to escape.
Additionally, a flexible IMJ could act as a “shock absorber,” helping the T-rex’s jaw muscles avoid injury during attacks or when subduing its prey.
Tyrannosaurus rex attacking prey. (Image: Scified).
The ability to crush the bones of its prey gave the T-rex a significant advantage over many other carnivorous dinosaurs that lived at the same time. They also had the capability to scavenge the remains of large dinosaurs for nutrition.
“When the T-rex fed on prey, such as a Triceratops, its bone-crushing ability allowed it to extract nutrients not only from the meat but also from the marrow. Compared to other carnivorous animals, the T-rex obtained more energy from its meals,” said Gregory Erickson, a member of the research team.
The research team indicated that their model could be utilized in the future to study the feeding mechanisms of many other dinosaur species in greater detail.
The Tyrannosaurus rex appeared around 68 million years ago and was one of the last land-dwelling dinosaurs. They existed only for a brief period before the mass extinction event at the end of the Cretaceous period.
An adult T-rex had a jaw length of about 1.2 meters containing 60 teeth longer than 30.5 cm. They also possessed large olfactory nerves, allowing them to smell food from a distance of up to 1 mile, approximately 1.6 kilometers.
Despite being a fearsome predator, based on data collected from fossils, scientists determined that the T-rex had a lifespan of only about 30 years, relatively short compared to other four-legged dinosaurs that could live up to 100 years.
Thomas Holtz, a paleontologist at the University of Maryland who is not part of the research team, remarked: “The T-rex did not have an easy existence. To become an adult T-rex, it had to survive from hatching out of its egg and make it through its juvenile stage. One could say this species (T-rex) is a product of a long evolutionary history.”
