The Lowly Appendix

Most of us are born with an appendix, a small dead-end tube attached to the colon, where the small and large intestines meet. For decades, scientists were baffled by this little biological mystery. The appendix didn't seem to do anything. Unless it go inflamed of course... in which case, the appendix could burst, cause a serious infection and possibly even death.

Most often though, the person suffering from appendicitis got to a hospital, the surgeons operated, removed the appendix and all went well. The person suffered no ill effects and the body didn't seem to operate any less efficiently.

So, the lowly appendix was considered to be a weird vestigial appendage that may have done something useful in the past, but no longer. That's what I thought for many years. But recent studies have shown something different.

Appendix function diagram by WebHamster - Wikipedia.
Licensed under CC BY-SA 3.0 via Wikimedia Commons

Turns out the little dead-end appendix has a one way valve where it meets up with the colon. Material can get out of the appendix but not into it. Which is kind of weird. Scientists now think that the lowly appendix serves as a reservoir of healthy gut bacteria.

For example, if you get a tummy bug that causes diarrhea (think a C. difficile infection), the infection moves everything through your gut and cleans everything out. But your gut needs good bacteria in order to function - and the appendix releases them out into the colon to assist in the healthy recovery of the digestive system. The idea that people who have had appendectomies don't experience any ill effects also isn't exactly true. People without an appendix are four times more likely to be reinfected by C. difficile.

Soooo... not a lowly appendix but actually a hardworking member of the human digestive system.

Which makes me wonder about the hubris of science. Just because we can't see an obvious use for something doesn't necessarily mean there isn't one. There are so many insects in the world, so many plants, so many animals, so much sea life. Just because we don't understand the purpose of something... doesn't mean it doesn't have a purpose. Just because something doesn't appear to be useful doesn't mean it doesn't serve an important function.

Today, we are losing insects, plants and animals at an alarming rate. Climate change, loss of habitat, pollution - all play a role in the extinction rate. The scary thing is... we really don't know what we are losing. We don't know the purpose of all of those organisms... or their usefulness.

For example, the West Coast of British Columbia is seeing an unprecedented collapse in starfish populations - courtesy of sea star wasting disease. It's caused by a pathogen and exacerbated by warming ocean temperatures. What will happen to the coastal marine ecosystem? We don't know. Do we care? After all, it's only starfish??

As humans, we think we are the most important creatures on the planet. The truth is... the planet will survive without us... plants, animals, insects, sea life... we really won't be missed.