And why it will not be evolved away any time soon.

For a long time, culture has been debating the vestigial status of the veriform appendix in the human body. There’s a significant new theory about the historical and current purpose of our appendix that seems to be holding water quite well . Well enough in fact that it is gathering supportive physiologists like wildfire. The explanation is almost too simple.

Before I go into it, I just thought you should know that your intestines are a cesspool of bacteria. I’m serious. They have an insanely high concentration of bacteria – about 13 million bacteria per gram of feces. Before you start wondering about how you can flush those massive clumps of microorganisms out, you should know that out of all the bacteria we’ve identified in this world, less than one percent is harmful to humans. A lot of bacteria is beneficial – even essential, and the bacteria in between serves its purpose by bullying out any new harmful bacteria trying to settle in your body. Bacteria is fantastic protection against sickness. The natural infestations of bacteria in our bodies are the most important thing keeping us from contracting every single cold we come in contact with. Our natural immune system is great, but completely blocking a virus from getting into your body in the first place is the reason our immune system isn’t always exhausted.

Here is where it gets interesting. When our bodies get diarrhea, I mean serious diarrhea – the kind where you have to drink an extra gallon of water just to keep hydrated – it is our body’s attempt to flush out the intestines and get rid of the bacteria or the chemical or whatever it is that is attacking your insides. This is great for taking care of the problem at hand, but all that flushing out removes most of the bacteria – beneficial included – from our system. And our bodies don’t make bacteria. Can you see how that could be a problem? Virus and malevolent bacteria can get in through the intestine and go absolutely nuts. If too much of the beneficial bacteria is flushed out, there is nobody to stop them, nobody on the way, and nothing you can do about it until you go to the doctor with your serious infection and they give you antibiotics. In third world countries where antibiotics are scarce, sometimes the final step in that sequence is death instead of antibiotics. That being the case, you might wonder why every time you have diarrhea you don’t get a serious series of illness and infections.

This is where the invaluable appendix comes in and saves the day.

An appendix is a long worm shaped pouch hanging off the side of our intestines. Specifically in the right iliac fossa. And it is specifically designed to be able to keep 99.99999% of our fecal matter out of it. But not the bacteria. That is right. It is an internal hotel for bacteria. This is where they kick up their feet, take a snooze, chat it up with the boys, and basically wait around for something to happen. When your intestines get flushed in an emergency, these guys start coming out and multiplying as fast as they can. If you were healthy before, you can safely assume that the guys that fill your appendix are friendlies and having them take up all the seats in your intestinal buffet is preferable to what was in there making the trouble in the first place, plus a lot less risky than what might be coming through in the near future.

That is all there is to it. The appendix holds bacteria in reserve to replenish the bacterial equilibrium when it gets flushed out. There will always be bacteria remaining in your intestines that will gradually return things to a healthy balance after a flush, so if you don’t have your appendix any more, you probably won’t get sick unless you eat something over the next few days that is contaminated – a common situation in much of the undeveloped world. In the cases where this happens in the developed world antibiotics are an easy cure, in the rest of the world, the appendix is an invaluable aid to staying alive.

Still a theory, but so far its the best and most likely one. Maybe it will start going into textbooks. And maybe pigs will grow wings and fly. They still illustrate the atom in most textbooks like a solar system.