These vestigial structures in our bodies are unnecessary for survival, and in some cases they are just a nuisance.
If you've ever had to get them surgically removed, you're lucky you didn't have to get rid of something that's crucially needed for your body to function.
Although we can live without these vestigial structures, we tend to wonder why we have them in the first place.
There's nothing more frustrating than learning that wisdom teeth don't make you wise and are solely there to cause you pain. It cost thousands to surgically remove and are the reason why we have countless annoying post-wisdom teeth surgery videos on the Internet.
Our ancestors used to have massive jaws that helped them chow down all those uncooked foods, so they needed those four extra teeth at the back. It's also believed that their teeth didn't last for long, so having those molars helped them to eat normally and possibly survive for longer. Our jaws shrunk as we evolved, so now there's no space for our wisdom teeth to grow painlessly.
Woman have two of the same sex chromosomes (XX), whereas men have two different sex chromosomes (XY). However, all embryos begin female until the (Y) chromosome kicks in. When this happens approximately 6-8 weeks later, the male keeps many of the same features. A female's breasts develop due to increased estrogen production, but that's not the case for men, so they are stuck with a flat chest with two brown circles.
One of the most dreaded parts to shave on your body is of no use to you now, but perhaps it used to be. Some scientists believe that the sweat gland in your armpit was useful for sexual signaling. The idea is that your body secretes odors that clings onto your armpit hairs, and then when a potential mate comes along and catches a whiff of your sex pheromones, they'll want to stick around you for longer.
Now, it's up to you if you want to throw out that deodorant stick.
It's believed that the appendix played a role in the digestive process, since it's close to the large and small intestines. In fact, it was useful at a time when humans consumed uncooked or low-quality foods, such as grass. A study in 2009 showed that the appendix may serve a function in storing some healthy bacteria that can help people suffering from diarrhea.
There's four more you need to know about!