Triceratops was built for a wrestling match — horns locked, head down

Horned dinosaurs wore their weapons on their faces — but how did they actually fight? A University of Bristol team built 3-D models of skulls from five horned species and tested, in simulation, which moves each skull could take without breaking. The small early Psittacosaurus was wise to stay out of trouble, and Protoceratops could handle a ram. Centrosaurus shrugged off up-and-down stabbing with its nose horn but not side-to-side twists, while Triceratops and Spiclypeus were built for locking horns and wrestling — much like deer and antelope today. The PeerJ study suggests the horns may have started as display, then became working weapons.