The Tyrannosaurus rex, a carnivorous theropod that thrived in the Late Cretaceous period, had a high concentration of nerves in its lower jaw, suggesting it may have served as a tactile sensor, according to a dinosaur research institute in central Japan.
In a paper recently published in a scientific journal of paleobiology, a team at Fukui Prefectural University's Dinosaur Research Institute said the discovery was made after performing CT scans of a well-preserved fossil of the T-Rex's jaw to closely examine the morphology of its internal blood vessels and neurovascular canals.
Soichiro Kawabe, an associate professor at the institute, believes that high tactile sensitivity of the lower jaw was likely used for movements involving precision, such as "catching prey, building nests, raising offspring, and communicating with other members of the same species."
The team discovered that neurovascular canals within the Tyrannosaurus' dentary branched out in more complex ways than those of herbivorous dinosaurs such as the Triceratops and Fukuisaurus, with the complexity particularly evident at the tip of the jaw.
According to the researchers, the complexity is comparable to that of extant crocodiles, which are known to have very sharp senses.
It is believed that the more complex the branching, the higher the density of nerves.
The analyzed fossil, dated approximately 68 million to 66 million years old and excavated in the U.S. state of Montana, currently forms part of the collection at Fukui Prefectural Dinosaur Museum.
Built in 2000, the museum in Katsuyama, Fukui Prefecture, is the largest in Japan and exhibits around 41,000 items in about 15,000 square meters of floor space, according to the official website.
Local government officials have said that more than 80 percent of dinosaur fossils discovered in the country are dug up in the prefecture.
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