Anyway, I was reminded the other day of my own suboptimally designed structures. In humans, the air-way crosses the food path leading to the possibility that you can choke every time you breathe while you are eating. For most people, this results in mostly just choking; however, for me, it is more common for food to go the other way, and then it gets stuck up my nose. It is terrible, awful. Seriously, terrible.
Other things I think may qualify as suboptimal design (disclaimer, I'm sure many of these have functions which I'm not aware of):
- Nerves in teeth. Seriously, root canals, tooth aches, temperature sensitivity, all terrible.
- The natural body odor of humans is generally repulsive in scent to other humans. I haven't heard of any other animal which is repulsed by its own scent; generally, it's the opposite, it attracts mates.
- The structure of our eyes, as well as many other animal eyes, is such that we have a blind spot.
- Appendices which lead to appendicitis. I'm pretty sure the appendix is vestigal, but appendicitis can be pretty risky and painful.