NSF-SNSF: Uncovering the evolutionary and developmental roots of the modern human body form

The evolution of the modern human form, with its characteristic long legs and comparatively short arms, is yet to be fully understood. This project investigates this problem by examining the fossil remains of juvenile human ancestors. The study informs how the modern human body shape evolved and contributes to the understanding of modern human adaptability and physical capabilities. This project employs advanced virtual imaging techniques and morphometric methods. By sharing the discoveries through public lectures, educational programs, and collaborations with museums, the project aims to engage and educate the public about modern humans’ ancient ancestors. This study advances scientific knowledge in developmental biology and medicine, providing educational opportunities that inform students and the public at large about human history and origins. The transition from the ancestral body shape of australopithecines to the modern human form remains unclear. To bridge this knowledge gap, this study addresses the challenge of understanding body size, proportions, and growth patterns in early Homo species, by focusing on Homo erectus. Since Homo erectus is the first hominin whose postcranial body shape is similar to the one observed in modern humans, analyzing the ontogeny of this species is fundamental to the evolutionary understanding of the the modern human body shape, body energetics, locomotion, and behaviors like long-distance walking and endurance running. Research goals include comparing growth patterns in axial and appendicular skeletons and validating anatomical reconstructions with high-resolution CT and nano-CT imaging of Nariokotome and the subadult skeleton from Dmanisi. In addition, understanding the relationship between axial and appendicular skeletons through cellular anabolic deposition patterns enhances knowledge of human skeletal growth, shedding light on the developmental processes that shaped our species. This collaborative U.S.-Swiss project is supported by the U.S. National Science Foundation (NSF) and the Swiss National Science Foundation (SNSF), where NSF funds the U.S. investigator and SNSF funds the partners in Switzerland. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.