MILFs and the sex they may or may not be having might not seem like an appropriate subject for a blog dedicated to the differences between men and women but believe me there is a point here, over and above the merely grubby. There’s also something of an explanation for that more recent invention, the “cougar”, he sexually predatory older woman.

Recent research has shown that older women are indeed more open to a sexual advance, more likely to indulge in sex:

Reproduction expediting: Sexual motivations, fantasies, and the ticking biological clock

Judith Easton, Jaime Confer, Cari Goetz & David Buss
Personality and Individual Differences, forthcoming

Abstract: Beginning in their late twenties, women face the unique adaptive problem of declining fertility eventually terminating at menopause. We hypothesize women have evolved a reproduction expediting psychological adaptation designed to capitalize on their remaining fertility. The present study tested predictions based on this hypothesis—these women will experience increased sexual motivations and sexual behaviors compared to women not facing a similar fertility decline. Results from college and community samples (N = 827) indicated women with declining fertility think more about sex, have more frequent and intense sexual fantasies, are more willing to engage in sexual intercourse, and report actually engaging in sexual intercourse more frequently than women of other age groups. These findings suggest women’s “biological clock” may function to shift psychological motivations and actual behaviors to facilitate utilizing remaining fertility.

In case you think this is an oddity, they’ve found something there that isn’t really there, there’s other, entirely different, research which leads to the same point. That ticking of the biological clock is a much more powerful impetus than many give it credit for at present.

The explanation for the more sex is simple enough: while we may, with our modern contraception, think we’ve managed to divorce sex from children and their conception the underlying urges of a 100,000 years of evolution aren’t quite so easily overcome. The body itself does recognise that time is getting short for having a or more children and is thus willing to engage more frequently in behavior which might lead to such.

The confirming evidence is from the known rise in genetic disorders like Down’s Syndrome in older mothers. There’s good evidence (amounting to the best explanation so far even if short of absolute proof) that the rate of genetic abnormalities in blastocysts (the fertilised egg before implantation in the uterine wall) doesn’t change much with age in women. The difference in observed abnormalities at birth is that more of the non-perfect blastocysts are able to attach themselves to that uterine wall….and the supposition is that that same biological clock is ticking.

If there’s plenty of time to have children then the spontaneous abortion of a damaged blastocyst is a sensible reaction: another month or two and a further pregnancy could well be contracted instead of spending 9 months pregnant and a year sucking the imperfect one. But if menopause is approaching and there are few (and always an unknown number) of those future opportunities then perhaps accepting the damaged balstocyst is the best available option: a child even if not a perfect one.

That two entirely different lines of reasoning lead to the same conclusion, that increased sexual appetite and increased receptiveness to damaged genes, illustrate the importance of the biological clock…well, they support each other, sure, but they don’t actually prove that either or both are correct. Just bolster them.