Its full name is Vermiform Appendix: “Vermiform” being Latin for “worm-shaped”, which describes the shape of this it. The human appendix is a 5-to-10 cm (2-to-4 inch) worm-like long protrusion jutting off the large intestine right by where the large and small intestine meet. Considered a “vestigial organ” — something that has lost its function through evolution — there is no general consensus among scientists about what the appendix’s actual purpose is.

However, recent a recent study from Duke University may have finally figured out the great mystery of the appendix’s function: a storehouse for “good bacteria” needed for digestion in the intestine. A side effect of diseases that cause chronic diarrhea — like cholera and dysentery — is that they can wipe out all the bacteria we need for digestion. It’s in situations like this, the study speculates, that our appendix would replenish this missing “good bacteria”.

This would also explain why we are capable of living without them. Appendicitis, or inflammation of the appendix, almost always results in the removal of the appendix and is one of the most common causes of acute abdominal pain. The classic signs of appendicitis are: pain in the stomach area first, followed by vomiting, and finally a fever. As appendicitis continues, the pain tends to focus in the lower-right quadrant of the abdomen.

So if we don’t need them, why is appendicitis so common? Scientists attribute this to what the refer to as the “hygiene hypothesis”. Basically, it purports that because our ultra-hygienic society rarely exposes us to dangerous pathogens, when we actually are, our bodies tend to overreact. There are fewer complications if you have your appendix removed before it ruptures, so of you have some intense pain in your abdomen you should see a doctor immediately. Have you had your appendix removed? If so, be sure to share your experiences in the comments section below.