Doctoral Dissertation Improvement: Ontogeny of Bipedalism: Pedal Mechanics and Trabecular Bone Morphology

University Of Texas At Austin, Austin TX

Investigators

Abstract

Walking on two feet (bipedal walking) is a hallmark of human behavior that matures gradually throughout development. The way in which the foot contacts the ground, and thus the way in which foot bones are loaded during walking, differ in toddlers and adults. As toddlers grow, the shape and structure of their internal (trabecular) bone also changes. The objective of this study is to document concurrent developmental changes in human foot bone loading and internal bone structure within a comparative context. Additionally, this study uses comparative data from living apes and humans to determine the nature and development of walking adaptations in early human ancestors (Australopithecus afarensis). This study consists of three main parts: 1) an experimental analysis of forces that load the foot during bipedal walking in human toddlers, 2) a micro CT scan analysis of trabecular structure in human and African ape foot bones that receive high forces during walking, and 3) a trabecular analysis of juvenile and adult A. afarensis foot bones. By identifying functionally significant anatomical correlates to bipedal walking within human foot bones, this study will help resolve debate regarding the extent to which bipedal walking in A. afarensis resembled that of modern humans. Moreover, this study will examine the bipedalism of A. afarensis in greater detail than previous studies because it will be the first to infer bipedal development from foot bones in this fossil species. Beyond the scope of physical anthropology, this study has clinical implications for pediatric orthopedics including the study of normal and pathological bone changes in juveniles. This project will also expand research opportunities available to undergraduates by affording undergraduate students (particularly members of under-represented groups) the opportunity to obtain hands-on research experience by aiding in data collection.