Teeth tied them together: scientists discovered a link between ancient dinosaurs and mammals

Dinosaurs and mammals united by teeth

Researchers found a surprising connection between prehistoric dinosaurs and mammals. It lies in their teeth. Introducing ancient dinosaurs, people think that they possessed sharp fangs, like saber-toothed tigers. But in the world of prehistoric animals, theropods are known for actually having razor-sharp teeth with which they easily ripped open their prey. Until recently, the complex arrangement of tissues that formed such sharp teeth has been considered unique only to predatory dinosaurs.

However, the scientists from Harvard University, examining thin sections of gorgonopsia, found the same complex tissue structure in tepopods, namely, notches that resemble sharp knives. Professor Megan Whitney explained that gorgonopsia are the forerunners of modern mammals.

These animals lived on our planet about 250 million years ago. They were vicious predators, and their saber fangs reached a length of 13 centimeters. The intricate tissue included enamel and dentin, which form the jagged teeth. But that structural arrangement was considered unique only to theropods.

Previously, no one performed a slice analysis of a Gorgonopsia's teeth to examine the jaggedness. Inspired by that discovery, the scientists are studying the microstructure of fossils and other prehistoric creatures belonging to three types of synapsids from different time periods.

It turned out that they all have the same notches, and they were present in animals of different periods of time. All three species Gorgonopsian, Dimetrodon and Smilodon, like theropods, were predators and had saber-shaped sharp teeth.

But they all fall into a category of mammals that is different from the reptile line of dinosaurs. The scientists say that all three species are even closer to humans than to dinosaurs. The fact that this type of teeth only develops in meat-eating animals is of great importance in evolution.

Tiny microstructures are hidden inside the teeth that not only strengthen the jaws, allowing the teeth to remain intact for longer, but also help the animal to effectively deal with prey.

Reference: “Convergent dental adaptations in the serrations of hypercarnivorous synapsids and dinosaurs” by M.R. Whitney, A.R.H. LeBlanc, A.R. Reynolds, K.S. Brink, 15 December 2020, Biology Letters. DOI: 10.1098/rsbl.2020.0750