felix said:
Time after time one would hear some loud mouth say "You don't want her, she's too easy" as if to imply that sex ought to be difficult. I could never see any logic in this attitude, especially since all the girls were listening in. Talk about c**pping in your own nest! If there's some Darwinian reason why a minority of men should deride the very women they desire most I haven't figured it out yet.
There is a very good Darwinian reason! To stand most chance of passing on your genes with any one female, you stand a better chance if yours are the only sperm she is impregnated with. If you attempt to impregnate a woman who has received the spendings of 10 men in the last few days, there is a lesser chance that your genes will be passed on.
Some species get around this through design: according to this guy at work, the chimpanze **** is of such a design that other chimps' sperm is drawn out of the lady chimp's tuppence. Others simply produce vast quantities of the stuff: compare the size of a cat's nads in comparison with the rest of him, against the size of human nads. For humans, the most effective way is just to make sure no-one else gets to have a go on your woman, and that you shouldn't waste resources on a woman who stands a good chance of mothering someone else's child instead of yours
There's your Darwin!
Also, sex shouldn't be too easy, where's the sense of achievement then? Life would be boring if it was a matter of "Oi, you, come here and drop 'em!"... after a couple of weeks, anyway
Easiest thing of all would be paying a prostitute (probably cheaper than a date!), but it wouldn't be very sporting.