Legs and posture

• All dinosaurs had four limbs. Unlike certain other reptiles, such as snakes and slowworms, they did not lose their limbs through evolution.

• Some dinosaurs, such as massive, plant-eating sauropods like Janenschia, stood and walked on all four legs nearly all the time.

• The all-fours method of standing and walking is called "quadrupedal."

• Some dinosaurs, such as nimble, meat-eating dromaeosaurs like Deinonychus, stood and walked on their back limbs only. The front two limbs were used as arms.

• The back-limbs-only method of standing and walking is called "bipedal."

• Some dinosaurs, such as hadrosaurs like Edmontosaurus, could move on all four limbs or just on their back legs if they chose to.

• The two-or-four-legs method of standing and walking is called "bipedal/quadrupedal."

• Reptiles such as lizards and crocodiles have a sprawling posture, in which the upper legs join the body at the sides.

• Dinosaurs had an upright posture, with the legs directly below the body.

• The more efficient upright posture and gait may be one major reason why dinosaurs were so successful compared to other animals of the time.

By: Parker, Steve, Dinosaurs