"Teeth tell us a lot more about the ecology of animals than just looking at the skeleton," he continued. "We already know from fossil evidence which animals existed at that time but now, with this type of research, we are starting to piece together how the members of these communities interacted."
Photos: Dinosaurs of a Feather Come Together
Based on other known animals living at the time of Dimetrodon's existence, the toothy predator probably hunted prey such as large fish, aquatic amphibians, and certain land animals, including reptiles. It might have also snacked on insects that were around then.
Reisz and graduate student Kirstin Brink, who led the study, used high tech equipment, such as a scanning electron microscope (SEM), to get an ultra close-up look at Dimetrodon's teeth.
In addition to its ziphodont (a.k.a. steak knife) teeth, this carnivore also sported cusps -- teeth with raised points on the crown -- which are dominant in mammals.
It's now thought that this over 13-foot-long very ancient animal was a forerunner to mammals. That's amazing to consider, given the reconstruction of Dimetrodon with its Spinosaurus-type "sail" on its back, turtle-looking head and more.