Tyrannosaurus rex is the big star - but he was only one of numerous representatives of the species-rich group of tyrannosaurs. US paleontologists have now added a new species to this famous Dino family: Daspletosaurus horneri, whose remains have been discovered in the US state of Montana. This predatory dinosaur lived about 74 million years ago and reached a length of about nine meters - he was thus slightly smaller than his later cousin T. rex.
"Instinct" around the mouth
Researchers were able to draw conclusions about the features of the face of the animals through findings on the well-preserved fossil skull remnants of three specimens of Daspletosaurus horneri. They had a lipless, dandruff-covered face with regions of hard and protective armor skin around their snout and jaw. In addition, the researchers discovered characteristic structures that they identified as Foramina: small openings for nerves. According to the researchers, these were probably associated with the trigeminal nerve, which in many creatures transmits stimuli to the brain.
Presumably, these features were present in all representatives of the tyrannosaurs and made their muzzles extremely sensitive, say the paleontologists. Similar structures still lend high sensitivity to the mouths of crocodiles and alligators. "The possible link to the trigeminal nerve is particularly interesting because it has an extraordinary evolutionary history - it has become a sixth-order mediator in different vertebrates, " says co-author Jayc Sedlmayr of Louisiana State University at Baton Rouge. "For example, it plays a role in capturing magnetic fields in birds or mediating the stimuli of whiskers in mammals."
Sensibility for the "Tyranno Kiss"?
But why needed the tyrannosaurs sensitivity in their weapon-raging snouts? As the researchers explain, the mouth of these predatory dinosaurs probably did not just serve killing and feeding - it probably also had to act as a kind of hand. They may have gently moved their eggs or kittens or felt the temperature of the nest. In addition, according to the researchers, there is another possible function for a sensitive snout: the mating behavior. "Tyrannosaurs could have rubbed their sensitive faces together - as part of foreplay, " the scientists write. Similar behaviors are still known today by crocodiles. display
Original work of the researchers:
- Scientific Reports, doi: 10.1038 / srep44942