By David B. Weishampel
The Ornithopoda, one among 5 suborders in the Ornithischia, used to be initially proposed via Marsh in 1881 to incorporate these bipedal dinosaurs owning a predentary bone outfitted over the rostral finish of the mandibles. Ornithopods as well-known at the present time might be additional characterised via reasonably lengthy facial skele plenty outfitted with well-developed, usually toothless premaxillae and average to giant exterior nares. Maxillary and dentary dentitions range yet frequently include no less than one alternative sequence underneath the practical set; a few have many rows of successional the teeth. enamel morphology indicates ornithopods have been suc cessful herbivores yet, as might be mentioned, the ideal way(s) within which ornitho pods chewed their foodstuff, therefore lending very important information regarding their tro phic place, has no longer been settled. Postcranially, ornithopods convey specializa tion for bipedality in hindlimb development and absence well-developed protecting buildings on their flanks, again, and tail. The Ornithopoda can itself be divided into 5 households: Fabrosauridae, He terodontosauridae, Hypsilophodontidae, 19uanodontidae, and Hadrosauridae (subdivided into the subfamilies Hadrosaurinae and Lambeosaurinae). either fabrosaurids and heterodontosaurids, first identified from the past due Triassic and Early Jurassic of Argentina and South Africa, have been small animals differing in information of cranial, dental, and appendicular anatomy. Fabrosaurids are be lieved to symbolize the basal ornithopod inventory (Galton 1972, 1978; Thulborn 1970a, 1972). through the Jurassic, ornithopods underwent significant radiations that integrated the medium- to large-sized Hypsilophodontidae and the massive bodied Iguanodontidae, either one of which survived into the Cretaceous.