[aimor]

I see this in my own beard hairs. I'll have a dark hair with a grey root, but then I'll also have a grey hair with a dark root. I didn't do any research into it, but I always felt like I saw more of the latter when I'd been getting lots of sleep.

Other hairy questions I've been curious about: What's the deal with that one long dark hair on my shoulder, and why is there one in about the same place on each shoulder? Why does it feel so good to pluck out some hairs, but other ones give a lot of resistance and hurt? Why do some hairs grow in pairs? Is body hair effective at baffling mosquitos?