Washington, Dec 9 (ANI): A new study, using CT scans, has revealed that dinosaurs had more air cavities in their heads than expected.
By using CT scans, Ohio University researchers Lawrence Witmer and Ryan Ridgely were able to develop 3-D images of the dinosaur skulls that show a clearer picture of the physiology of the airways.
"I've been looking at sinuses for a long time, and indeed people would kid me about studying nothing-looking at the empty spaces in the skull. But what's emerged is that these air spaces have certain properties and functions," said Witmer, Chang Professor of Paleontology in Ohio University's College of Osteopathic Medicine.
Witmer and Ridgely examined skulls from two predators, Tyrannosaurus rex and Majungasaurus, and two ankylosaurian dinosaurs, Panoplosaurus and Euoplocephalus, both plant eaters with armored bodies and short snouts.
For comparison, the scientists also studied scans of crocodiles and ostriches, which are modern day relatives of dinosaurs, as well as humans.
The analysis of the predatory dinosaurs revealed large olfactory areas, an arching airway that went from the nostrils to the throat, and many sinuses.
Overall, the amount of air space was much greater than the brain cavity.
The CT scans also allowed Witmer and Ridgely to calculate the volume of the bone, air space, muscle and other soft tissues to make an accurate estimate of how much these heads weighed when the animals were alive.
Witmer suggests that the air spaces helped lighten the load of the head, making it about 18 percent lighter than it would have been without all the air.
That savings in weight could have allowed the predators to put on more bone-crushing muscle or even to take larger prey.
These sinus cavities also may have played a biomechanical role by making the bones hollow, similar to the hollow beams used in construction. Both are incredibly strong, but don't weigh as much their solid counterparts.
A light but strong skull enabled these predators to move their heads more quickly and helped them hold their large heads up on cantilevered necks, explained Witmer.
Though most researchers have assumed that the nasal passages in armored dinosaurs would mimic the simple airways of the predators, Witmer and Ridgely found that these spaces actually were convoluted and complex.
The passages were twisted and corkscrewed in the beasts' snouts and didn't funnel directly to the lungs or air pockets.
"Not only do these guys have nasal cavities like crazy straws, they also have highly vascular snouts," said Witmer. (ANI)