Things I sometimes think about

So I'm writing this article about neti pots... what, you've never heard of neti pots? They're these little teapot-like things with long snouts that you use clean out your nasal passages. Yes, you pour water into one nostril and let it drip thru and out the other one. It's supposed to be great for allergies and all manner of ENT things. People on the Indian subcontinent irrigate their noses as often as Americans brush their teeth.

Anyway, it just struck me as weird that you have two holes in the front of your face that meet back inside your nose. Why two? Why not just one big one? Is it just the whole bilateral symmetry thing?

I mean, two eyes are a definite advantage - they give us two views of the same objects and thus stereoscopic vision, aka depth perception. Two ears give us enough parallax on a sound so that we can tell what direction it's coming from.

Are two nostrils supposed to help us tell where a smell is coming from? Can dogs tell?