edge of the jaw), like the blade of a penknife closing into its handle. This scissors-like action would have enabled rhynchosaurs to cut up tough plant material.

The teeth were unusual; those in the maxilla and palate were modified into broad tooth plates, with multiple rows of grinding teeth interspersed with grooves that shear against the lower jaw. Many rhynchosaur species can be distinguished from each other by the structure of their tooth plates. They had a fixed number of teeth, and similar to elephants,