To make a short story long... I got my hair cut today, which is something I loathe even more than having my teeth cleaned. (While the results are wonderful in both cases, there's just something awfully disturbing about trying to sit still while sharp/pointy objects are being applied to bits of my head.) As I was waiting for my turn in the chair, I was trying to think of interesting things not to talk to the hairdresser about. (Where did all the barbers go?) While I was staring vacantly at a picture of some lovely model with some lovely haircut vacantly staring back at me, I hit upon chromatophores as a suitable topic to concentrate on while I was being tormented for the next 20 minutes. It was the model's makeup. It occurred to me that chromatophores would be an absolute godsend to most of the women I know. Think of the time, money, and frustration (mostly incurred by male companions) that could have been saved, if only the vagaries of evolutionary pressure had so allowed. (BTW, what's the deal with eyeshadow? ) So here's what's been bothering me: How did cephalopod chromatophores evolve? Are there any good theories or studies that indicate how this might have happened? I'm having a hard time convincing myself of a plausible way around that "irreducible complexity" bunk.