Like eyelashes, present to prevent dirt, dust and other crazy crap from sliding down your forehead and into your eyes. Traditionally, having one eyebrow - that is, a uni-brow, like the nemesis of Maggy Simpson - is a sign of lycanthropy.

Mentats have long long eyebrows, and so does a prominent Japanese politician.

I want to transplant my goatee to where my eyebrows are so I can intimidate people even more when I waggle them Groucho Marx-style.