Apes and monkeys are sometimes described as having four hands, because the toes are long and the hallux is opposable and looks more like a thumb, thus enabling the feet to be used as hands. The hand is located at the distal end of each arm. Hands must also have opposable thumbs, as described later in the text. The only true grasping hands appear in the mammalian order of primates. The scientific use of the term hand in this sense to distinguish the terminations of the front paws from the hind ones is an example of anthropomorphism. Many mammals and other animals have grasping appendages similar in form to a hand such as paws, claws, and talons, but these are not scientifically considered to be grasping hands. Some evolutionary anatomists use the term hand to refer to the appendage of digits on the forelimb more generally - for example, in the context of whether the three digits of the bird hand involved the same homologous loss of two digits as in the dinosaur hand. Like other paired organs (eyes, feet, legs) each hand is dominantly controlled by the opposing brain hemisphere, so that handedness-the preferred hand choice for single-handed activities such as writing with a pencil, reflects individual brain functioning. They also have the greatest positioning capability of the body thus, the sense of touch is intimately associated with hands.
The raccoon is usually described as having "hands" though opposable thumbs are lacking.įingers contain some of the densest areas of nerve endings on the body, and are the richest source of tactile feedback.
A few other vertebrates such as the koala (which has two opposable thumbs on each "hand" and fingerprints remarkably similar to human fingerprints) are often described as having "hands" instead of paws on their front limbs. A hand is a prehensile, multi-fingered organ located at the end of the forearm or forelimb of primates such as humans, chimpanzees, monkeys, and lemurs.
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