Digital Advancements in Reconstructing Hominin Shoulder Evolution

Bio:

I am a paleoanthropologist interested in the australopiths—those fossil species that are undisputedly hominin, but certainly not human. I want to know what these animals looked like, how they moved and how they evolved. I received my PhD from Stanford University and did my post-doc at the Max Planck Institute for Evolutionary Anthropology (Leipzig, Germany). I am currently a visiting assistant professor at Mercyhurst University in the Department of Applied Forensic Sciences. I have conducted paleoanthropological fieldwork at multiple sites in Ethiopia and Djibouti, but my primary involvement is at the site of Woranso-Mille (Afar Region, Ethiopia) where I have worked since 2006. I like being outdoors, bicycles, maps, trying new food, and everything related to bones and fossils.  

Abstract:

Bipedalism is a defining characteristic of the hominins. Paleoanthropologists have documented numerous adaptations that made this novel form of locomotion possible, with particular emphasis on the pelvic girdle and lower limb. However, the evolution of bipedalism also marks a major functional transition for the shoulder girdle and upper limb—from playing a central role in body propulsion in an arboreal ancestor to a non-propulsive and non-weight bearing role in fully terrestrial hominins. The shoulders of living humans differ markedly from other apes, so it is clear that substantial structural and morphological shifts occurred over the course of human evolution. How and when did these differences come to be? And what do they tell us about the ecological and behavioral changes that shaped our lineage?

I will talk about how digital advancements are helping us answer these questions. Fossils discovered in the past two decades, including the 3.6 Ma Australopithecus afarensis partial skeleton from Woranso-Mille (“Kadanuumuu”), allow us to trace the evolutionary history of hominin shoulder in much more detail than previously possible. Virtual models of the human and ape musculoskeletal system provide a new outlook on how differences in skeletal form affect function. Methodological improvements in computer-based fossil reconstruction and skeletal articulation challenge long-held ideas about how we can use fossils to detect shifts in skeletal structure. Expanding these lines of research in the future will allow us to construct data-driven movement simulations for extinct human ancestors, and provide a deeper understanding of their biomechanical capabilities.