A dinosaur isn't just a scary lizard! Dinosaurs are scaly ancestors of lizards, but there's more to it! Dinosaurs stood on 2 legs or more with their legs directly underneath them, not bowed out like their ancestors. They laid hard eggs and traveled in herds, and they migrated from pole to pole! One way a dinosaur is a dinosaur is by their hip type. Dinosaurs are separated into two groups, Ornithischian and Saurischian. Saurischians were the scary big carnivores and the HUGE saurpods. Ornithischians were the calm Hadrosaurs and small carnivores. Saurischian is lizard-hipped and Ornithischians were bird-hipped.