Nicholas Holowka

ABSTRACT SUBMITTED: Bipedal walking is one of the defining traits of hominins, and walking long distances has been a critical part of human subsistence for most of our species’ existence. However, most knowledge of human walking biomechanics and energetics derives from laboratory studies whose conditions cannot simulate the complex natural terrains our species evolved to walk and forage on. To better understand human walking under more representative conditions, this study quantified forest walking energetics and kinematics in Batek and Semai communities in Peninsular Malaysia. Forty-one participants were recorded walking on roads, trails, and forests using state-of-the-art wireless motion capture and portable metabolic equipment. Forest terrains caused participants to spend almost twice as much energy as when walking on flat even roads and forced them to walk with more crouched postures and wider steps. These results indicate that foraging in complex natural environments like forests entails much higher energy expenditure than previously appreciated, which has important implications for human subsistence ecology. Further, these results suggest that the significance of safety and versatility in the evolution of hominin locomotion has been overlooked, and thus future studies should identify anatomical adaptations that have made these critical features of human gait possible.