Medary.com

OK So I'm Not Really A Cowboy meditates upon the (supposed) uselessness of the appendix:

The gut is a highly specialized and complex organ system. It has its own separate nervous system, an amazing range of hormonal functionality, forms an important part of the immune system, and, of course, digests our food. The appendix has lost the latter function, but retained the rest. Which doesn’t necessarily make it an important part of the body, just means that it’s only truly vestigial in one respect.