The primary objective of this research is to understand and interpret the anatomical changes that took place in the human back during the transition to bipedalism among our ancestors. This is a biological problem of considerble interest to anthropologists and the results will be directly relevant to reconstructing locomotor behavior and the transformation to bipedality in the fossil record. The first step in solving this problem will be to conduct a thorough description of the musculoskeletal anatomy of the back of apes and an analysis of its function in locomotion. The proposed study will combine (1) osteometric comparision of the lower thoracic and lumbar regions of the back among humans, apes, and other selected primates; (2) comparative dissections of the muscles of this region in the same species; and, (3) cineradiographic analysis of the movements of the vertebral column in several species, so that functional hypotheses can be verified more objectively. Anthropologists currently disagree on both the posture and locomotion that likely characterized our prebipedal ancestor and on the identification of fully modern bipedality in the fossil record. The results of this study will contribute to our knowledge of locomotor analysis and function in the living apes, and identify anatomical correlates to upright posture in several types of primates. Moreover, it should prove valuable to future understanding of the origin of human bipedalism.
