Hadrosauridae is a branch of the dinosaurs at the foot of a bird, a group of prosperous herbivorous dinosaurs, including the famous Edmontosaurus, Parasaurolophus fossils found in Asia, Europe, North America and Lower Cretaceous strata. They are the Upper Jurassic Iguanodon progeny class and have similar size. Hadrosaurid can be divided into two subfamilies. Lambeosaurinae has a large head crest or tubular, more lightweight body. Hadrosaurinae head crest or lack of tubular, few species have a hard crown, the larger body.