The question is finding a physiological purpose for a physiological phenomenon. Some, like Donald Symons, even argue that the female orgasm itself is non-adaptive because most female mammals do not experiece orgasm in ordinary copulation. They only experiece orgasm through clitoral stimulation.
or
"clitoral orgasm is a paradox not only for the traditions of Darwinian biology but also for the bias of utility that underlies all functionally based theories of evolution and,in addition, the much older tradition of natural theology, that saw God's handiwork in the exquisite fit of an organic form to function."
"We (men) simply cannot abide by the idea --though it flows from obvious biology-- that a women's sexual pleasure might not arise from our own coital efforts."
"the clitoris is the homologue of the penis--it is the same organ, endowed with the same anatomical organization and capacity of response...the clitoris and the penis are one and the same organ, identical in early form, but later enlarged in male fetuses through the action of testosterone. Similarly, the labia majora of women and scrotal sacs of men are the same structure, indistinguishable in young embryos, but later enlarged, folded over and fused along the midline in male fetuses." S.J. Gould, "Tits and Clits".
> oh, i like this: if the phenomenon doesn't fit the totalizing
> theory, it's a 'hangover.'
Well then, what explains its existence? Adaptation is one evolutionary force among many (a minority view.)
> and your theory on the glans of the penis would be? oh, and
> don't forget to explain how pressure on the frenum can, um,
> suppress ejaculation--surely there's a functionalist expla-
> nation for that, say, to encourage e-commerce or something.
>
All adaptationist arguments are functional in structure. The beneficial effects of having x explain x's existence.
> i say that by way of avoiding taking up your suggestion that
> pleasure for females is a 'hangover from a previous period.'
>
No. The point is that pleasure for females is divorced from procreation making a Darwinian explanation unlikely.
> indeed. and male nipples are a signpost on the road to, oh,
> never mind...
yes, your ancestors probably lactated.
Sam Pawlett