Toothsome Talk

Professor Robert Reisz
Wednesday, December 14, 2016 - 5:18pm
Carla DeMarco
A dental examination of the teeth and lips of dinosaurs by U of T Mississauga’s 2016 Research Excellence Award winner, Professor Robert Reisz.

Department of Biology Prof Robert Reisz has nothing against movies about dinosaurs, and he can actually appreciate their fantastical depiction. But don’t get him started on the inaccurate portrayal of the teeth and lack of lips on these creatures.

“This is something that really has bugged me for much of my career,” says Reisz, showing a colourful still from a film.

“Reconstructions in movies and even in prestigious museums have these teeth sticking out. They do show the smaller ones, the ‘raptors,’ with lips, but not the larger allosaurid and tyrannosaurid dinosaurs because the teeth are so huge, especially in Tyrannosaurus. Their large size made it difficult for people to imagine how those teeth could fit inside the mouth. And yet, the delicate nature of the serrations along the cutting edges of these teeth are difficult to imagine remaining undamaged if exposed continually.”

These are the types of dental details Reisz teased out over the course of an hour for the Annual Research Excellence Lecture, which he delivered as this year’s award recipient. He covered the growth patterns and structure of teeth in reptiles, and how they are different from that of mammals.

“There are two major ways in which teeth attach to the jaw,” says Reisz.

“Teeth can be fused to the jaw (ankylosis) as in many reptiles, or sitting in a deep socket and loosely attached with periodontal ligaments (gomphosis), as in crocodiles and mammals. Gomphosis is particularly interesting because it allows for some slight movement of the tooth during biting, but why did mammals, crocodiles, and dinosaurs evolve this type of attachment?” Reisz and his team continue to explore these kinds interesting mysteries.

The audience in the Instructional Building at UTM attending the lecture was a mix of faculty, librarians, students and staff from various departments, and they went on to fête Reisz further at a reception held in his honour in the atrium afterwards.

Accolades have been plentiful and consistent over Reisz’s 40-year career as a vertebrate paleontologist at UTM, including a Bass Fellowship at the Field Museum of Natural History in Chicago, an Invited Professorship at the National Museum of Natural History in Paris, a Fellow of both the American Association for the Advancement of Science and the Royal Society of Canada, Academy of Science, and, most recently in September 2016, being awarded a lifetime Honorary Professorship at Jilin University in China, where he was also named the Honorary Director of their newly established Dinosaur Evolution Research Centre.

With all this worldwide recognition however it is clear that Reisz loves his work at UTM, and he is quick to gives props to his long-standing lab personnel, including Dianne Scott, who encouraged him to pursue this line of tooth research, as well as the grad students, staff and colleagues that he has worked with over the years.

The sentiment was reciprocal in UTM Vice-Principal, Research Bryan Stewart’s closing remarks that Reisz has been a stalwart ambassador for UTM and an “inspiring mentor” to colleagues such as himself.