The appendicular skeleton is composed of the pectoral (or fore) limb and the pelvic (or hind) Iimb and the shoulder and pelvic girdles which attach these to the bexly.

The forelimb has no bony connection to the trunk, only being attached by muscles. T his absorbs the ’shock’ at the point when the limb takes the ani­mal's weight in four legged animals or running quadrupeds. This differs from primates, which gener­ally walk on their hind legs and so have evolved a pec­toral girdle with a clavicle. However, the hindlimb docs have a bony articulation in the pelvic girdle, which forms the platform for the muscles that provide the propulsive force as the animal is running.