The Tyrannosaurus rex , one of the largest carnivorous dinosaurs to roam the earth, had an air conditioner in the head, show the work of American scientists from the universities of Missouri, Ohio and Florida.
Researcher Casey Holliday, a professor of anatomy at the University of Missouri, and his colleagues explain that the two large holes (temporal fossae) located in his skull acted as an internal air conditioner, which helped the beast evacuate the warmth of his body.
This explanation calls into question another widely held hypothesis in the paleontological community that these orifices were filled with muscles supporting the movement of the animal’s jaw.
An interpretation that left some scientists perplexed, the authors of the present works who think rather that this area was filled with blood vessels allowing the dinosaur to regulate its temperature.
It would be really weird for a muscle to come out of the jaw, make a 90 degree turn, and skirt the skull.
We now have a lot of convincing evidence of the presence of blood vessels there, based on our work with alligators and other reptiles , says the professor.
Did you know?
- The first significant remains of T. rex were discovered in 1902 and the animal was described and baptized by Henry Fairfield Osborn in 1905.
- Teeth and other fossilized bones discovered in 1874 and 1890 in Colorado and Wyoming were poorly identified and were subsequently reclassified as T. rex elements.
- Whole skeletal discoveries, in 1988 (in Montana) and 1990 (South Dakota), helped to better understand the anatomy of the dinosaur.
This evidence comes from observation work done using thermal imaging devices that convert heat into visible light. The researchers were able to examine the alligators of a farm in St. Augustine, Florida.
“The body heat of an alligator depends on its environment,” says Kent Vliet, Department of Biology at the University of Florida.
As a result of these field observations, the research team examined fossilized remains of dinosaurs and crocodiles to see how these holes in the skull have changed over time. We know that, just like T. rex, alligators have holes in their skulls and they are filled with blood vessels , says Larry Witmer, professor of anatomy at the University of Ohio.
For more than 100 years, we thought that similar holes in the skull of the dinosaurs were populated with muscles. Using the anatomy and physiology of current animals, we reverse these hypotheses on the anatomy of this part of the skull of T. rex.
The details of this work are published in The Anatomical Record.