Long Bone Shape: A Family Affair

Although humans and chimpanzees move quite differently, muscle attachment sites at their thighbones are similar. This result, which has recently been published by anthropologists of Zurich University in the scientific journal «Anatomical Record», has major consequences for the interpretation of fossil hominin finds.

PhD student Naoki Morimoto, member of the Computer-Assisted Paleoanthropology group of Ch. Zollikofer and M. Ponce de León, and junior author of the study, was surprised by his own findings. Although humans are bipeds, and chimps are quadrupeds, muscle attachment sites at their thighbones are quite similar. Attachment sites differ substantially, however, between chimpanzees and gorillas, although these great apes species move similarly. Interestingly, Morimoto’s results are in line with insights from genetics: humans and chimps are evolutionary sister species, while gorillas are more distant relatives, like cousins. Morimoto explains the seeming paradox of his results: this is not «form follows function», but «form follows family». Continue reading