The human body may be a masterwork of engineering. However, like all evolutionarily derived systems, it has its share of useless body parts. Check out these weird leftovers from our evolutionary past.
Gender Inappropriate Stuff
We all know that men have nipples that seemingly have no purpose, but did you know that men also have an undeveloped uterus? It hangs off the male prostate gland and does nothing whatsoever. Perhaps even stranger is the female vas deferens–what would become the sperm ducts in a male instead grows into what the field of anatomy calls the parovarium, a cluster of tubules that accomplish nothing at all in the female body.
Things You May Have Heard
Almost everyone knows that the appendix is useless. In fact, many people have them removed in order to prevent infection. Then there’s wisdom teeth, which tend to come out poorly in 95 percent of humans today, making it sometimes necessary to have them removed. Another item you’re sure to have noticed before are goosebumps; the erector pili muscles that create them are useful only if you’re covered in hair. Since we’re mostly hairless, our goosebumps can never achieve the puffing up of fur that they so desperately try to do when we get scared. Speaking of which, body hair serves no purpose at all unless it covers a significant portion of the body. Even the hairiest guy out there has no real use for the hair he has covering his body.
Some of the things the human body has lost would be exceedingly awesome if we got it back. The paranasal sinuses, for example, used to be lined with odor receptors that gave an extremely acute sense of smell. Too bad the odor receptors in that area don’t exist any longer in humans. Of even more awesomeness is the vomeronasal organ, which is lined with chemoreceptors that for some reason are no longer connected to our brains. Back when this bad boy worked on early humans, it could detect all kinds of different phermones, making the human nose nearly as powerful as a dog’s.
The sense of smell isn’t the only latent superpower the human body holds in its evolutionary history. Today, the extrinsic ear muscles allow many people to wiggle their ears, but back when our ears were more focused, those same muscles would allow us to pinpoint our ears in a certain direction, greatly increasing our ability to hear from a long distance. Another ear artifact is Darwin’s point, a small fold of skin at the top of everyone’s ears that used to direct soundwaves to the eardrum like a satellite dish.
Perhaps the most interesting useless body parts the human body has are actually listed in the Bible. Eve was made from the rib of Adam. There do exist some people who are born not just with our usual twelve ribs, but also with a thirteenth set. It’s not a rare condition, either; about 8% of the population are born with this extra set of ribs.
Another interesting one isn’t found in the Bible, but is well attested to in the Christian tradition: Satan and other devils, it is said, have a third eyelid that blinks independently of the eyelids we all know and love. Usually, this description is explained by being what you normally see on birds and reptiles. On other animals, this third eyelid is useful for clearing the eye of debris and protecting it in an emergency. Humans retain a very tiny fold in the corner of each eye that no longer has the ability to blink and now serves no useful purpose. However, in a very small segment of the population, humans can be born whose third eyelid is large enough to actually halfway blink. It is from these people that the legends of devil eyelids were first formed.