Blog Post Image: Fossil indicates hairy, squirrel-sized creature was not quite a mammal

Skeletal features show that Megaconus was a terrestrial animal with an ambulatory (“walking”) gait, similar to a modern rock hyrax or armadillo. This new fossil species has features in common with modern mammals, but its first cheek tooth has a large, cone-shaped cusp, resulting in its name Megaconus mammaliaformis (“ancestral mammal with a big cusp”). Illustration by April Isch