Most of us realize the existence of our appendix only when it swells and leads to the famous appendicitis. Of course, that’s far from being a good memory… Since after removing it, people just carry on with their lives as if nothing ever happened, it was thought to have become useless. But actually studies have shown that the appendix protects your immune system by hosting healthy bacteria that regulate your intestinal flora.
That might sound a bit vague, so let’s break it down a bit. When we have certain types of diseases, like gastroenteritis, that our body wants to clean up at all costs. That’s when it starts to get rid of bacteria, but it does so without distinguishing the good bacteria from the bad. And as you might have understood already, not all of them are “bad guys” in this story, and our stomach actually needs bacteria to work properly. So they don’t get washed away with the others, the good guys are supposed to take shelter in the appendix and, when everything goes back to business as usual, they continue growing normally. Sure, all that sounds useful, but, in reality, today we use our appendix far less than our ancestors did when their diet was rougher and had to perform different digestive functions.
Our coccyx is located on our spine and kind of gives away something a bit embarrassing: our ancestors had a tail! Yup, and it was a long tail. It used to perform the important function of helping them to maintain balance and mobility, but as our species learned to walk upright, it lost its purpose and now only has the secondary function of acting as a link between muscles, tendons, and ligaments. Well, that might explain why it hasn’t completely disappeared from our body together with the tail.
4. Vomeronasal organ
The vomeronasal organ is considered to be an auxiliary organ that is related to your sense of smell. It is located in the nasal cavity, so basically inside your nose. Many animal species have it, but actually, in our species it’s nothing more than a vestigial organ, a sort of “leftover” from evolution. Scientists have not been able to find evidence of any active sensory neurons like those animals have, so that they can properly use this part of their bodies.
5. Wisdom teeth
Wisdom teeth might be the teeth we are least likely to miss when we’re at the dentist for them to be removed. Noticing their presence is usually bad news, because it means that they are disturbing something. And while they might be a hassle for us, they were very important to our ancestors. They used them to grind up plant tissue.
In fact, some studies claim that the skulls of our ancestors had larger jaws and more teeth. As human eating habits changed, our jaws evolved to become smaller. It seems that the third molars didn’t get the memo saying that there was no room for them in our small mouths anymore… They just keep on growing, even though they have no function. How annoying! And actually, they are often more harmful than anything else, so dentists choose to remove them.