Scientists have identified a new tyrannosaur species that lived in what is modern-day Montana about 74 million years ago. The new species Daspletosaurus horneri was approximately 29 feet long and 7.2 feet tall. It was not as big as the fearsome T. rex, but the new species had an incredible sixth sense that helped it locate prey and identify nearby objects.
The tyrannosaur’s fossils were found in 1992
The new species was described Thursday in the journal Scientific Reports. Lead author Thomas Carr of the Carthage College in Kenosha said the discovery has “literally changed” the face of tyrannosaurs. D. horneri had small patches of armor-like skin. The beasts had hypersensitive snouts protected by flat scales. Carr and his colleagues found the new tyrannosaur’s snouts were similar to those of crocodiles.
The crocs rely on their sensitive snouts to sense pressure waves underwater and the temperature of nests. D. horneri fossils were first recovered in 1992. Paleontologists at the time gave it the nickname “Two Medicine tyrannosaurine” after the site where it was unearthed. However, it was identified as a species only in 2017 by Thomas Carr and his colleagues. The species was named after the US paleontologist John Horner. Daspletosaurus horneri literally translates to “Horner’s Frightful Lizard.”
Trigeminal nerves give D. horneri its ‘sixth sense’
Scientists analyzed the well-preserved fossils such as jaws, skulls, and other bones belonging to adults and younglings. Then they compared the texture on the beast’s skull bones with those of other modern animals. The comparative analysis revealed that the roughness on D. horneri was similar to the roughness of the crocodile snout bones.
Carr said in a statement that the texture of crocodilian bones changed due to the skin covering the bones. Paleontologists used this clue to identify what tissues covered what on the tyrannosaur’s face. Crocodiles get their facial scales because their bones grow faster than the skin covering them. It results into cracking of the skin.
Carr said the texture of bones and the small holes in the facial bones of D. horneri indicate that its snout was as sensitive as crocodile snouts. The tiny holes act as channels for nerves and blood vessels. Carr and his colleagues said the trigeminal nerves passed through the small holes in the dinosaur’s facial homes. Trigeminal nerves are the transmitting nerves that provide sensation.
The same nerves in the beaks allow birds to sense touch and temperature. The same nerves in crocodiles help them sense tiny vibrations in murky waters, and give the sense of electroreception to platypus bill.