Fossil Discovery Reveals Early Plant-Eating Land Vertebrate

A fossilized skull unearthed on Cape Breton Island, Nova Scotia, has been identified as belonging to Tyrannoroter heberti, a species that lived approximately 307 million years ago. This discovery suggests that early land vertebrates began experimenting with plant-based diets sooner than previously believed.

The skull, about 10 centimeters long, features specialized teeth adapted for crushing and grinding vegetation. High-resolution micro-CT scans revealed multiple rows of conical teeth on the roof of the mouth, indicative of herbivorous feeding habits. The genus name Tyrannoroter translates to "tyrant digger," reflecting its relatively large size for its time and presumed burrowing behavior. The species name heberti honors Brian Hebert, the amateur paleontologist who discovered the fossil.

Arjan Mann, assistant curator of fossil fishes and early tetrapods at the Field Museum in Chicago and co-lead author of the study, stated, :

"This is one of the oldest known four-legged animals to eat its veggies. It shows that experimentation with herbivory goes all the way back to the earliest terrestrial tetrapods—the ancient relatives of all land vertebrates, including us."

The findings, published in Nature Ecology & Evolution, indicate that terrestrial herbivory originated rapidly following the transition of tetrapods to land. The study also suggests that insect-eating may have been a precursor to plant-eating, as consuming herbivorous insects could have introduced gut flora necessary for digesting plant material.

This discovery provides new insights into the evolution of herbivory among early land vertebrates and highlights the adaptability of these ancient creatures in exploiting available food resources.