Article: Deducing the body posture of extinct large vertebrates from the shape of the vertebral column

Simple measurements were taken from the vertebral column of several extinct and extant terrestrial vertebrates in order to estimate the bending moments in a sagittal plane that could be sustained along the longitudinal body axis. According to theoretical expectations, the estimated patterns of sustainable bending moments prove to differ between bipeds and quadrupeds of different body proportions. In an analysis of the vertebral column of the dinosaurs Plateosaurus and Iguanodon, the former appears as a habitual quadruped, while the latter must have assumed a bipedal posture more frequently or carried most weight on the hindlimbs during quadrupedal locomotion. A separate analysis of the cross sectional areas of the vertebral centra and the lever arms of the epaxial muscles gives further information on the use of the vertebral column during locomotion and reveals aspects of the ecology of the animals under study.