Knuckle-walking - Related Forms of Hand-walking

Related Forms of Hand-walking

Primates can walk on their hands in other ways than on their knuckles. They can walk on fists such as orangutans. In this body weight is borne on the back of the proximal phalanges.

Quadrupedal primate walking can be done on the palms. This occurs in many primates when walking on all fours on tree branches. It is also the method used by human infants when crawling on their knees or engaged in a "bear-crawl" (in which the legs are fully extended and weight in taken by the ankles). A few older children and some adults retain the ability to walk quadrupedally, even after acquiring bipedally. A BBC2 and NOVA in The Family That Walks On All Fours reported on the Ulas family in which five individuals grew up walking normally upon the palms of their hands and fully extended legs due to a recessive genetic mutation that causes a non-progressive congenital cerebellar ataxia that impairs the balance need for bipedality. Not only did they walk on their palms of their hands but could do so holding objects in their fingers.

Primates can also walk on their fingers. In Olive Baboons, Rhesus Macaques, and Patas Monkeys such finger walking turns to palm walking when animals start to run. This has been suggested to spread the forces better across the wrist bones to protect them.