A football-size creature may have been among the earliest plant-eating land animals

Researchers describe Tyrannoroter heberti, a football-sized tetrapod known from a 307-million-year-old skull found in Nova Scotia, and report tooth wear and palate teeth consistent with a plant-based diet. The authors say this suggests herbivory among early four-limbed vertebrates appeared sooner and in more groups than previously thought.

A newly described tetrapod, Tyrannoroter heberti, is known from a skull found in a fossilized tree stump along the cliffs of Cape Breton Island, Nova Scotia. The fossil is dated to about 307 million years ago and was reported in Nature Ecology & Evolution. The skull is wide and heart-shaped and the animal is described as a chunky, football-sized creature. Researchers used CT scans, electron microscopy, and 3D scanning and printing to study the skull and its tooth surfaces. Key findings: - The skull was found in a fossilized tree stump on Cape Breton Island and the species name honors discoverer Brian Hebert. - The animal has a wide, heart-shaped skull and rows of large, interlocking teeth on the palate and lower jaw suited for grinding. - CT scans and electron microscopes revealed wear facets on those teeth, which the authors report as evidence consistent with a plant-based diet. - The fossil is dated to the middle Carboniferous (about 307 million years ago) and was described in Nature Ecology & Evolution. - The research team and outside commentators say the find implies herbivory arose earlier after tetrapods became fully terrestrial and may have evolved independently in multiple lineages. - The authors noted that climate shifts from wetter to more arid environments may have reduced the plants these animals relied on and could have contributed to the lineage's disappearance. Summary: The discovery of Tyrannoroter heberti suggests that plant-eating appeared soon after some vertebrates became fully terrestrial and that herbivory may have evolved multiple times among early tetrapods. Undetermined at this time.