October 29, 2008
Study Finds T. Rex Had Stellar Smeller
New research from the University of Calgary and the Royal Tyrrell Museum in Alberta, Canada, finds that the Tyrannosaurus rex tops the list of carnivorous dinosaurs when it comes to sense of smell.
The scientists examined the size of the dinosaurs' olfactory bulbs, a part of the brain that regulates smell, using CT scans and measurements of fossilized skulls for a number of meat-eating dinosaurs known as Theropods.
They discovered that the Tyrannosaurus edged out all the other Theropods in the study, which included large predators such as the South American giant Giganotosaurus, smaller raptors such as the African killer Carcharodontosaurus and even the primitive bird Archaeopteryx.
"T. rex had a very good sense of smell," Francois Therrien of the Royal Tyrrell Museum told Reuters.
"Probably that's how they located prey and patrolled a large territory."
Although the scientists were not the first to discover T. rex's superior sense of smell, they were first to rate the infamous dinosaur in comparison to other Theropods.
Some experts have said that T. rex's superior sense of smell proves the dinosaur was more a scavenger than an active hunter, but Therrien disagreed.
"It has been suggested that the very good sense of smell of T. rex indicated that it was a scavenger because it would have used its sense of smell to locate putrefying carcasses on the landscape," he said.
"But when we look at modern animals, we see that's not the case. Scavengers don't necessarily have a better sense of smell. You have some like the turkey vultures that have a good sense of smell. But you have other scavengers like the Old World vultures that actually have a typical sense of smell because they use sight instead of smell to locate prey."
The researchers said the small but ferocious Velociraptor and its relatives also had an outstanding sense of smell, whereas ostrich-like dinosaurs such as the Ornithomimus and the Oviraptor were lacking in their sense of smell.
The Archaeopteryx, the earliest known bird with fossils dating to 150 million years ago, proved to have a fairly good sense of smell, in keeping with the meat-eating dinosaurs from which experts believe the birds evolved, the researchers said.
The study was published in the British journal Proceedings of the Royal Society B.
On the Net: