T. rex dinosaurs are real assassins

A new study shows that Tyrannosaurus rex must rely on a quick nose to detect victims as well as defeat live prey at night.

Some scientists have previously considered T. rex to be a scavenger, not a true assassin because they have many different characteristics including extremely sensitive smell. In the new study analyzing data from many of the predatory dinosaurs and carnivores like the American crocodile, T. rex dinosaurs seem to be the true predators, they defeat them all. Prey are other dinosaurs.

To get this information, paleontologist Darla Zelenitsky of the University of Calgary in Alberta (Canada) and his colleagues studied the importance of olfaction for theropod-eating dinosaurs, based on size. Their olfactory bulb size as well as the brain region is related to olfactory function. Although the dinosaur brain is not preserved, the impression of the brain area left on the skull bone or the space that the brain holds in the skull reveals the size and shape of the different parts of the brain. .

In the survival battle, T. rex dinosaurs are not only frightening by terrible teeth or huge body sizes.Its super-large olfactory bulb also helps the tyrant to sniff the prey whether it is day or night.(Photo: Courtesy of Royal Tyrrell Museum)

The researchers used computerized scanners and display samples in the museum or skulls to obtain information about the diversity of theropods (including raptors and species). ostrich-like dinosaurs), ancient Archeopteryx bird and American crocodile.

While tyrannosaurs, including T. rex dinosaurs, and Velociraptor dinosaurs, nicknamed 'speed bird' have the largest olfactory bulb corresponding to brain size and body weight, species. The ability to have the worst sense of smell according to the size of the olfactory bulb is oviraptor and the ostrich ornithomimid dinosaur.

Zelenitsky said: 'Perhaps they are less olfactory, this may mean they have a herbivorous or omnivorous diet'. Zelenitsky added that previous studies also showed that oviraptorid and ornithomimid dinosaurs could be herbivorous or omnivorous.

'Oversized' olfactory bulb also proves T. rex dinosaurs and its relatives, such as the Gorgosaurus libratus dinosaur, whose feathers all rely on sharp sense of smell to find their prey at night or find their children. bait in large territories.

An image of an ornithomimid eating dinosaur skull showing the olfactory bulb (red) and forehead (green).(Photo: Courtesy of Yoshitsugu Kobayashi)

Zelenitsky said: 'Large olfactory bulb is also present in modern birds and mammals based on the sense of smell to find food, primitive predators or species that live in large areas. Big also carries this characteristic. Although the lord of carnivorous dinosaurs does not eat corpses, they may have used their sense of smell at night or to orient themselves in large territories in search of the next victim. '

The extinct Archeopteryx bird, thought to have evolved from small carnivorous dinosaurs, has an olfactory bulb size comparable to most theropod dinosaurs. Most birds today have sharp eyes but lack the sense of smell. This shows that the smell has become less important at certain times in the ancient history of bird development.

The study was published in detail in the current issue of the Proceedings of the Royal Society B.