Pachycephalosaurs

Pachycephalosaurs were very similar to Ornithopods because of their bipedal stance and similar tendons along the back. They had spoon shaped teeth used for eating vegetation. Their skulls were thicker on the top, giving them a smoothly domed head, considered to be used for headbutting. They came in many different sizes with the early ones being 2.5 metres long but the later ones growing up to 5 metres long.