Ancient skull rewrites plant-eating origins

A chunky, squat creature from 307 million years ago is reshaping our understanding of early land life. Scientists have identified Tyrannoroter heberti, a species that represents one of the earliest four-limbed animals with a confirmed plant-based diet. Its fossilized skull, discovered in a tree stump on Nova Scotia's Cape Breton Island, suggests early tetrapods began consuming vegetation around the middle of the Carboniferous Period.

Researchers utilized 3D scanning and printing to meticulously study the skull, revealing a football-sized, reptile-like animal with a wide, heart-shaped skull and rows of teeth designed to grind tough plants. This adaptation for herbivory provides crucial insights into the development of terrestrial ecosystems shortly after vertebrates fully transitioned to land, indicating plant-eating evolved earlier than previously believed.

The broader implications suggest that four-limbed vertebrates rapidly diversified their diets upon becoming land dwellers, potentially paving the way for later, widespread herbivory. This evolutionary shift may have been influenced by changing climates, leading some early herbivores to disappear as plant life adapted to more arid environments.