Quantitative and functional studies on the hands of the anthropoidea. I. The Hominoidea

Abstract The hands of the Hominoidea evidence four adaptive modes which distinguish the lesse apes (Hylobatidae), the orangutan ( Pongo ), the African apes ( Pan ), and man ( Homo ) from one another. The hands of the apes consist of compromises between manipulatory and locomotor functions because selection has operated for precision of grip as well as for special locomotor mechanisms. The human hand is almost totally devoted to manipulation. The hands of gibbons, orangutans and the African apes differ in many features that may be correlated with locomotion. The gibbons and siamang are specially adapted for ricochetal arm‐swinging. The great apes possess morphological adaptations for arboreal foraging and climbing distinct from those of the hylobatids. In addition, the African apes have become secondarily adapted for terrestrial quadrupedal locomotion. Many features that distinguish the hands of chimpanzees and gorillas may be associated with the development of efficient knuckele‐walking propulsive and support mechanisms.