Foot Function and the Evolution of Human Gait

Professor Richmond and colleagues' discovery in 2007-08 of 1.5 million year old sites preserving hominin (human ancestors and relatives) footprints in Kenya (Bennett et al. 2009; Richmond et al., 2010), featured on the cover of Science, now provides an unparalleled source of evidence regarding the evolution of human foot anatomy, function, and gait. However, analyses of these fossil footprints exposed how little research has been conducted on the formation of footprints, despite the importance for understanding the origin of human gait and relevance to other fields (e.g., forensic science). Experiments in MOCA involve people walking and running at measured speeds on various sediments with controlled variation in moisture and particle size (which dictates how cohesive the mud behaves), and comparing the 3D topography of the resulting footprints with foot function. The development of deformable object-capture instrument will allow us to understand how sediment deforms around the moving foot to produce footprint shape; this, in turn, will allow us to more accurately reconstruct foot function from these and other ancient footprints (Leakey & Hay, 1979; Richmond et al., 2011) made by species with foot anatomy and function that are unique from ours today.