Butting heads
A 2013 study by University of Wisconsin OshKosh researchers revealed that domeheaded dinosaurs may have butted heads in combat
Bonehead dinosaurs
Pachycephalosaurs were plant eating dinosaurs that roamed during the Late Cretaceous Period. They grew large domes on their head made of bone, and the domes were often encircled by spikes.
Bighorn battles
Lots of animals scuffle over turf or mates. Bighorn sheep lock horns over territory and ewes.
Crocodile fight
Crocodiles are known to bite viciously at each other in squabbles.
T. rex bites
Even dinosaurs show evidence of fighting amongst themselves. Bite marks on juvenile T. rex fossils indicate that they may have bitten each other.
Common injuries
To understand pachycephalosaur behavior better, Joseph Peterson, a geology professor at the University of Wisconsin Oshkosh and his colleagues analyzed skulls from the dome-headed dinosaurs.
Frequent injuries
The team analyzed more than 100 skulls from museums around the world, using in-person analysis, high-resolution photographs, and CT scanning.
Extensive injuries
The team found that roughly 20 percent of the dinos had injuries, such as pit marks, on their skulls.
Similar profile
The pit marks bore a close resemblance to injuries found on bighorn sheep skeletons. In sheep, the pitting is caused when they butt heads in combat.
Fighting dinosaurs
The boneheaded dinosaurs likely sustained their injuries when bashing their heads against rivals.
Skin infection
Those impacts may have broken the skin, causing infections.