1Anatomy, Valladolid University, 2Anatomy, Howard University, 3CASHP, George Washington University
Saturday All day, Plaza Level
In this presentation we report the results of an analysis of the attachments, relative weights, innervation and functional morphology of the lower limb muscles of three chimpanzees, one gorilla, two orangutans, three gibbons and various modern humans. Our dissections and literature review revealed that: 1) in modern humans and Asian apes the gluteus maximus is the largest gluteal muscle, whereas in African apes it is the gluteus medius; 2) the scansorius is larger in Pongo than in other hominoids; 3) the plantaris is often present in hylobatids; 4) within hominoids, an exclusive femoral origin of the popliteus is only found in gorillas and modern humans; 5) the relative weight of the deep gluteal muscles, which are mainly involved in lateral rotation of the thigh, is greater in Asian apes than in African Apes. The relative weights of the muscles involved favor flexion, abduction and medial rotation at the hip joint, plantar flexion and inversion at the ankle joint and within the foot, toe flexion. At the knee, the extensors predominate in hylobatids, the flexors in Pongo and Gorilla; in Pan the relative weights of the knee flexors and extensors are subequal.
We gratefully acknowledge the support of the GW Signature Program, the Mathers Foundation and the GW Provost.