Many birds are thought to share characteristics with dinosaurs, but cassowaries have more in common with their fearsome ancestors than most. Cassowaries have casques (helmet-like structures on top of their heads), a feature that many dinosaurs are also thought to have possessed. The cassowary’s casque is made from a tough, elastic, foam-like material. Cassowaries also share a relatively large body size, fierce claws, and a roar-like call with their dinosaur ancestors.