Discovered: the basis of human civilization.

Here's more of the usual highly speculative sociobiology, but it's spicy and it's drawing the bloggy links, so let's take a look:

Women who fail to orgasm during sex may be genetically programmed to weed out unreliable men who are a flop between the sheets, according to new research.

Scientists who have studied the ability of thousands of women to climax say it is largely written in their genes - the most compelling evidence so far that the female orgasm has a biological role.

The findings suggest the failure of some women to orgasm regularly is not a dysfunction, but a sophisticated mate-selection strategy that evolved during prehistoric times.

Tim Spector of St Thomas's hospital in London, who led the research, said: "The theory is that the orgasm is an evolutionary way of seeing if men can prove themselves to be likely good providers or dependable, patient and caring enough to look after the kids."

Women who orgasm very easily may be more likely to be satisfied with poor quality men.

It looks as if all the achievements of human civilization ought to be attributed to how hard it is to satisfy us women. Men did plenty of the work over the millennia, but they wouldn't have bothered if we women hadn't needed something more than sex to impress us.

Keep trying, guys!