Monkey in the Middle.

What's in the monkey's mind when he looks in a mirror? Higher minds -- human beings, great apes, dolphins -- figure out, when they are looking in a mirror, that they are seeing themselves. Other animals, it's long been thought, think they're seeing a stranger. But a new study shows that the monkey occupies a middle position, where it doesn't see itself, but it doesn't see a stranger either. The monkey sees a "Puzzling Other."

And there's a sex difference. The males are disturbed by the Puzzling Other. The females try to flirt.

P.S. Did you use to play "Monkey in the Middle"? That was a very common kid's game when I was growing up. I suppose it would be considered too mean today. But it was a pretty fun game for three kids to play with just one small rubber ball. (There was also a similar game called "keep away.")