Pachycephalosaurus, skull dome Protoceratops The original specimen that this

The original specimen that this replica was cast from is from a private collection and is not available for sale

Complete specimens

an unusual example of parallel evolution

regardless of whether it is the growing trunks or the final uppermost branches

Pachycephalosaurus, skull dome Protoceratops The original specimen that thisPachycephalosaurus, meaning "thick headed lizard," is a genus of pachycephalosaurid dinosaurs. The type species, P. wyomingensis, is the only known species. It lived during the Late Cretaceous Period (Maastrichtian stage) of what is now North America. Remains have been excavated in Montana, South Dakota, and Wyoming. It was an herbivorous creature which is primarily known from a single skull and a few extremely thick skull roofs, though more complete