You asked us a question. "If we don't need an appendix, why is it there in the first place?"
Just because you don't need your appendix, does not mean it is useless.
For a long time people thought it was. Charles Darwin thought the appendix was shriveled. He thought it was a leftover organ. He figured it was used by early humans to help digest leaves. That has been the main way of thinking until recently.
That is the great thing about science. Sometimes everyone thinks one thing. And then someone else says, "Hey, I have a better explanation."
A team of researchers did just that. They wondered if it is not so much what the appendix does, but what it can hold.
Our bodies are like an apartment building. We have tenants living inside of us. These tenants are bacteria. There is about 10 times more bacteria in and on our bodies than in our actual cells.
But like all good tenants, they pay rent. The bacteria in our gut help us digest food. They help us make vitamins. Bacteria even help our immune system. That's right. Bacteria in our bodies helps our immune system fight other bacteria.
Sometimes invading bacteria get the best of our immune system. And then we get sick. Like, cholera sick or dysentery sick.
We are not trying to be gross. But we are talking life-threatening, never-ending diarrhea sick.
In cases like this, all your good gut bacteria could be washed out. That is unless they have a place to hunker down. Like the appendix.
Scientists think the appendix acts as a reserve. It is where good bacteria can hide until the illness is over. Then they re-emerge. And they repopulate the gut. It can go right back to helping us out.
You may not be that familiar with diseases like cholera or dysentery. That is because modern sewage systems have largely done away with them.
So in today's high tech world, you can live just fine without your appendix.
But you never know. Maybe sometime in the future, another scientist will have a better explanation.