This summer, the Kibale Chimpanzee Project welcomed a number of student researchers, including Nick Brazeau and Alex Smith from Harvard University. Nick, a rising senior, is working on his senior thesis project by collecting body size estimates of the Kanyawara chimpanzees. Alex, a rising junior, is his tireless research assistant. It is difficult to measure body sizes of wild chimpanzees, because researchers can’t easily convince them to climb onto scales. Instead we employ non-invasive methods like photogrammetry. Nick has assembled an apparatus that contains two laser beams mounted in parallel at a set distance of 5 cm. The laser apparatus is attached to a camera, and the projected beams provide a size reference in the photograph.
For each chimpanzee, Nick and Alex measure multiple body parts, including the forelimbs, hindlimbs, trunk, back, skull, and testes. These measurements will be compared to body size estimates of chimpanzees using multiple methods, including a comparison with captive chimpanzees of known weights. Such data will be valuable in answering questions about growth, life history, the relationship between body size and dominance, and the costs of locomotion.