We have… A lot of things inside our bodies. It’s a very complicated organic machine and our understanding of it is always evolving. But with complication comes redundancy, and you might be wondering what you do and don’t actually need to be a functional person. You’ve probably heard of the appendix as a common body part you don’t need–we don’t even really know what it is supposed to do anyway. We can kind of guess though. Appendix aside, what is the most useless body part? What other things could you live without–without really noticing all that much? Since, yeah, you could lose your hands or an eyeball or something–but that would have a pretty big impact on your daily life.
We referenced it earlier, so let’s get the appendix out of the way first. About 1 in 100,000 are just born without an appendix, and it’s pretty common knowledge that you can live with your appendix removed with relatively little consequence. In fact, we used to think the appendix was so useless it would just get straight up removed if you were having abdominal surgery. Evidence does suggest that the appendix plays a role in the endocrine system, at least for younger people and fetuses. For adults the appendix is thought to contribute to the immune system. So uh… We don’t just rip it out anymore.
Your Eye. Kind of. (Plica semilunaris)
Saying that your eye is a vestigial organ is obviously just a way to grab your attention–you very much need two eyes if you want to maintain depth perception. But there are parts of your eye that don’t help you out right now anymore. The plica semilunaris is a little fold in the inner eye, right by your tear duct. Not sure how effective or productive it would be to remove yours for the sake of proving a point.
Anyway, the plica semilunaris is probably a remnant of a third eyelid we may have had way back when.
If you’ve ever had your wisdom teeth removed, you probably hate them a lot. There also might be a fun video of you on laughing gas. Your wisdom teeth are just your third molars, and can get impacted because they come out improperly. Impacted wisdom teeth are normally a problem, which is why you have to get your wisdom teeth out if they’re displacing your other molars.
The Vomeronasal Organ
The very existence of the vomeronasal organ in humans is a debated topic. We do know that other animals do have a vomeronasal organ, and that it’s part of the olfactory system (the smell thing). There’s a good chance that the vomeronasal organ is used in picking up pheromones–either from prey, predators, or potential mates.
Evidence seems to suggest that the vomeronasal organ doesn’t have any significant presence in humans and other primates, though some experiments have shown that the vomeronasal organ probably exists in a very tiny, vestigial capacity within people. So vestigial that there probably aren’t even any nerves hooked up to it.
A Bunch of Muscles
There are a lot of muscles that we’re pretty sure are just useless. Many people are born without them, and carry on just fine. For example there’s the chondroglossus muscle in your tongue, discovered in a study done on 100 cadavers. About 86% of the muscles were associated with what was thought to be speech or chewing, while 14% of the muscle fibers were so thin that the chondroglossus muscle was deemed largely vestigial.
There’s also the plantaris muscle in your leg, which like 10% of people just don’t have. It probably helps move your knee or ankle, but is almost entirely redundant. The levator claviculae muscle is meant to move your clavicle around–but seems to be present in less than 5% of people.
Your ears have auricular muscles in them, which serve no other purpose than letting your friends wiggle their ears.
In your skin there are also the arrector pili muscles. They’re responsible for giving you goosebumps, which don’t serve much function now that we don’t have fur.
Further Reading: Why Do We Get Goosebumps? Why Are They Called That?
While you shouldn’t go and rip your spleen out, you can live relatively comfortably without one (at least in comparison to having something like your stomach removed). When removed, many other organs take the function of the spleen, as your liver also plays an important role in recycling blood cells (which the spleen also does). However, having your spleen removed does make you more susceptible to illness and infection, so it’s not like you could just have yours removed and not even notice.
See if you know which organs can be transplanted here.