MSG Tripps wrote:

The hidden cooch.

That's wonderful stuff, Dhal. Thanks.

This was accomplished, Morris says, through self-mimicry in which female breasts came to look like rounded buttocks: female breasts became mimics of “the ancient genital display of the hemispherical buttocks.”

I guess that's conceivable.

Szalay and Costello (1991) have continued this line of thinking, but argue that permanently enlarged breasts sexually arouse males not because they look like buttocks, but because they mimic the appearance of female genitalia.

That's less so.  If I came across a woman with a vagina on her chest, I'd be seriously freaked out.  Which probably wouldn't stop me from tapping it.

That was an interesting read.