Pachycephalosaurus wyomingensis was the largest of the pachycephalosaurids—"thick-headed dinosaurs"—which featured extremely thick skullcaps. The top of a Pachycephalosaurus skull could be 9 inches ...

Jurassic Park helped popularize this head butting dino. Learn why paleontologists are undecided about the evolution and behavior of the Pachycephalosaurus. Even if you don’t recognize that formality, ...

A specimen discovered in Mongolia is the most complete fossil yet found of a pachycephalosaur, a dinosaur believed to be built for head-butting. The skull of Zavacephale rinpoche, a pachycephalosaur ...

New end-stage juvenile specimens of Pachycephalosaurus from the Upper Cretaceous Hell Creek Formation, Montana, confirm the earliest expression of squamosal nodes, parietal ornamentation, and jugal ...

Did dome-headed dinosaurs really butt heads? While not one of the most important subjects in paleontology, the question is one of the most fraught. The thick-skulled dinosaurs look as if they were ...

Pachycephalosaurus, the delicately built, 15-foot-long, dome-headed dinosaur that lived alongside Tyrannosaurus and Triceratops, is a staple of children’s books and popular culture—one usually ...

A new species of dome-headed dinosaur has been discovered in fossils found in Montana, according to researchers.