With the recent announcement of the brand-new genus Texacephale (guess what state its fossil was found in?), pachycephalosaurs have been in the news lately. These "thick-headed lizards," as their name translates, boasted an inch or two of extra bone on top of their skulls, the only conceivable function for which could have been to head-butt others of the species and compete for mating privileges. Intrigued? Read all about pachycephalosaurs, including the lifestyle and behavior of this odd breed of herbivorous dinosaur as well as profiles of major species.