Charles Darwin identifies nearly a dozen human body parts as ‘useless’, in his book The Descent of Man. However, Darwin’s list of useless body parts is far from complete, as our bodies are equipped with many more body parts that renders no use to us. Let’s check them out.
#1 Body Hair
Body hair present in certain areas of the human body are definitely useful. For example; pubic hair protects the pubic region from infections, and eyebrows help to keep sweat away from eyes. Also, male facial hair plays role in attracting the opposite sex. But most body hair left on the human body, such as male chest hair, renders no exact function.
#2 Extrinsic Ear Muscles
Thanks to the presence of these muscles, animals like rabbits and dogs can wiggle their ears independently. However, they serve no clear purpose in humans.
#3 Paranasal Sinuses
Paranasal sinuses are a group of four paired air-filled spaces surrounding the nasal cavity. The maxillary, frontal, ethmoidal, and sphenoidal sinuses are present below the eyes, above the eyes, between the eyes, and behind the eyes, respectively. These mucus-lined cavities serve no clear purposes, except making the head lighter.
#4 Wisdom Teeth
Wisdom teeth is the troublesome third and final set of molars that grace the mouths of most people in their late teens or early twenties. These are often misaligned, and require removal. These useless set of teeth will be the first to disappear from the list, hopefully.
#5 Palmaris Muscle
This is a long narrow muscle which runs from the elbow to the wrist. It is absent in 11% of humans at the present. It was once important for hanging and climbing, and is useless for most of us at the present, unless you’re a martial artist or a rock-climber.
#6 Cervical Ribs
A set of utterly useless cervical ribs are still seen in less than 1% of human population. Some only have it on one side, while in others, cervical ribs are present in both sides. They commonly cause nerve and artery problems.
#7 Male Nipples
During the initial stages of fetal development, the fetus is sexless. This is why both males and females have nipples. However, men lack the levels of prolactin needed for lactation.
#8 Arrector Pili Muscles
These are small muscles which allow mammals to puff their hairs up. Although humans retained this ability, most of the fur are lost.
This is a narrow muscular tube which is located at the junction of the small intestine and the large intestine. When humans used to consume more plants than animal protein, appendix contributed for the digestion of cellulose. However, in the present, the function of the appendix is unknown.
#10 Thirteenth Rib
Some of the closest relations of humans such as chimpanzees and gorillas have an extra set of ribs. Although a vast majority of humans only possess 12 pairs of ribs, 8% of humans have a thirteenth pair.
This is also known as the tail-bone. Coccyx is the only part that’s remaining from the tail, which is still used by most mammals for communication and balance.
According to scientists, in early days, humans used to balance themselves and walk more on their feet’s middle line. But at the present, our point of balance has been gradually transferred to the side of the big toe. Humans’ center of balance is still shifting forward. These facts suggest that although humans used to heavily rely on their toes for balance, now this reliance is gradually reducing. If this continues, our toes will be useless.
#13 Third Eyelid
Third eyelid has protected the eye from debris in ancestors of birds and mammals. However, humans retain only a tiny fold which is located at the inner corner of the eye.
#14 Darwin’s Point
This is a small folded point at the top of the ear that’s rare in humans. It might be what’s remaining from a bigger ear that contributed in hearing sounds from a large distance.
#15 Subclavius Muscle
This is a small triangular muscle which is located between the clavicle and the first rib. This muscle stretches under the shoulders from the first rib to the collarbone. This muscle is still present in a tiny percentage of humans, and would’ve been useful if only humans were still walking on all fours.