Prosauropods were small to large (maximum lengths approximately 2.5 to 11 m), bipedal to quadupedal, plant-eating dinosaurs with small skulls and elongate necks (Figures 1A, C). They are basal members of the Sauropodomorpha, which include the giant sauropods of the Jurassic and Cretaceous. The Prosauropoda as a group is usually regarded as paraphyletic, because the general trends toward large size, quadrupedality, and herbivory seem to continue into the Sauropoda proper. However, a rigorous phylogenetic analysis of this question has not been made, and some evidence suggests that the prosauropods represent a radiation independent of the lineage leading to the more derived Sauropoda.