Chasmosaurus

Ceratopsians are split into two subfamilies, those with short frills and those with long frills like Chasmosaurus. The frills of Chasmosaurus were heart-shaped and very distinct. It has been theorized by some paleontologists that the frill may have been brightly colored in order to draw the attention of a potential mate.

The longer frilled ceratopsians also have longer faces and jaws than their short frilled cousins. This may have indicated that they subsisted on a different diet while sharing the same ecological niche.