Why we have body parts we don't need is simple. According to the Harvard Health website, they were most likely necessary at one point but eventually became nonessential through evolution. 

Apparently, we have quite a few body parts that we can, for the most part, live without.

We know about the appendix. It's always been considered that useless organ that basically sits there. The only time it's removed is when it gets infected, and emergency surgery is warranted before it bursts.

According to the Interesting Facts website, while it stores beneficial gut bacteria to be released when we're sick and lacking it, it's not important.

What was once a tail, our tailbone, technically called the coccyx, isn't part of human necessity as we've evolved over the centuries. According to the Interesting Facts website, thanks to our ancestors, human embryos generally form with a tail that disappears before birth; however, in rare cases, some babies have been born with a tail that is obviously removed.

Did you know that some people keep their wisdom teeth? I didn't even think there was room in the mouth for them. For those who keep them, we all know they're literally unnecessary. While our ancestors, who ate harder-to-chew things and didn’t have dentists, found these back-up teeth helpful, clearly, we've come a long way.

Medical shows always have a scene where doctors must remove someone's spleen. While it helps combat infection, according to the Mayo Clinic, the liver can take over if it's removed.

The tonsils are the same way. While they help fight infection, if they're removed, the worst that can happen is that you'll be more susceptible to colds and sore throats, especially as a kid. According to the Cleveland Clinic, other lymph nodes in our neck and throat can fight infection.

Gallbladder surgery is another common procedure we always hear about. Once again, the liver comes to the rescue, as the gallbladder isn't a necessity at all, according to the National Health Service website. Our liver can produce enough bile to digest food without it.

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