抄録
Anatomical features (shape, weight and myofibrous composition) of skeletal muscles reflect the muscular functions. In this study, we histologically analyzed the myofibrous composition of corresponding muscles and compared their functions in man and the macaque. Among the intrinsic hand and foot muscles, the hand muscles for gripping and pinching movements were well developed in humans and those for hanging were well developed in the hands and feet of the macaque. Of the spinohumeral muscles, morphological differences (thickness of muscle layer and muscle fiber size) were observed in different regions. In the muscles in the upper and lower extremities, the relative weight and myofibrous composition were correlated with the characteristics of their respective motions. There were differences in myofibrous composition among those muscle groups due to bipedal or quadrupedal walking by man and the macaque. The differences in the myofibrous composition of the muscles for vocalization (laryngeal muscles), and the innervation ratios of the muscle fibers reflected vocal ability.
