Feb 07, 2014 10:59 AM EST
Earth's Oldest Land Predators Had 'Steak Knife' Teeth
Earth's oldest land predators were not afraid to bite off more than they could chew, according to a recent study.
Researchers from the University of Toronto Mississauga in Canada found that Dimetrodon, a carnivore that walked on land between 298 million and 272 million years ago. They claim the predators were the first terrestrial vertebrate to develop serrated ziphodont, or "steak knife" teeth.
In the study, researchers said ziphodont teeth, with their serrated edges produced a more efficient bite and would have allowed Dimetrodon to eat prey much larger than itself.
Fossil evidence suggests that while most meat-eating dinosaurs possessed ziphodont teeth, serrated teeth first evolved in the Dimetrodon some 40 million years earlier than theropod dinosaurs.
"The steak-knife configuration of these teeth and the architecture of the skull suggest Dimetrodon was able to grab and rip and dismember large prey," Professor Robert Reisz said in a statement. "Teeth fossils have attracted a lot of attention in dinosaurs but much less is known about the animals that lived during this first chapter in terrestrial evolution."
Researchers said the four-meter-long carnivore was the top of the terrestrial food chain in the Early Permian Period and is considered to be the forerunner of mammals.
For the study Reisz and lead author of the study Kirstin Brink studied the changes in Dimetrodon teeth across 25 million years of evolution.
"Technologies such as scanning electron microscope (SEM) and histology allowed us to examine these teeth in detail to reveal previously unknown patterns in the evolutionary history of Dimetrodon," Brink said in a statement.
Based on their findings, Dimetrodon had a diversity of previously unknown tooth structures and were also the first terrestrial vertebrate to develop cusps - teeth with raised points on the crown, which are dominant in mammals.
The study also suggests ziphodont teeth were confined to later species of Dimetrodon, indicating a gradual change in feeding habits.
"This research is an important step in reconstructing the structure of ancient complex communities," Reisz said in a statement. "Teeth tell us a lot more about the ecology of animals than just looking at the skeleton."
Reisz added that the research piece together how animals interacted with each other millions of years ago.
Join the Conversation