The fore- and hind limbs were evolved basically for bearing the weight of
the body and for locomotion as is seen in quadrupeds,
Each limb is made up of a basal segment or
girdle, and a free part divided into proximal,
middle and distal segments. The girdle
attaches the limb to the axial skeleton.
The distal segment carries five digits.
However, with the evolution of the erect posture in man, the function of weight-bearing was taken over by the lower limbs.
Thus the upper limbs, especially the hands, became free and gradually evolved into organs having great manipulative skills.