Fig. 1-5
The weight line of an anthropoid ape such as the gorilla in the oblique quadrupedal position (left) falls between the forelimbs and the hindlimbs. In up-right-standing and -walking man, the axis of the body mass for the "center of gravity" passes from the occipital condyles of the cranial base, close to the vertebral column, through the hip joints on either side, and so to the tripodial feet. The peculiarly human form of bipedalism is a distinctive adaptation that was acquired early in the process of hominization. Its acquisition has been accompanied by anatomic adjustments affecting every part of the skeleton and locomotor apparatus from the cranial base to the feet. |