Book review: Why Women have Sex: Understanding Sexual Motivation | Why Men Want Sex & Women Need Love

Published on Saturday 3 October 2009 15:27

Why Women Have Sex: Understanding Sexual Motivation by Cindy Meston and David Buss The Bodley Head, 336pp, £12.99 Why Men Want Sex & Women Need Love by Allan & Barbara Pease Orion, 288pp, £12.99 Reviews by LIZ HOGGARD

IT'S NOT easy to read two volumes of evolutionary psychology on the bus without blushing. On the plus side, friends have never found me so interesting. Mention that there are 237 reasons women have sex and the room grows strangely quiet.

We know we find some faces and bodies "hot" but remain largely unaware of the hidden adaptive logic behind our desires. It's a sad fact that much of our modern, liberated behaviour comes down to ancient sexual psychology.

Trim waists, big breasts, V-shaped torsos – we're biologically "wired" to look for partners with genetic and resource benefits, even if we have no intention of marrying. The wealthier a man, the more frequently his partner orgasms. I can't go for a meal now without knowing that it's all part of the exchange of meat for sex.

Why Women Have Sex is billed as the new Kinsey Report. Cindy Meston, a professor of clinical psychology at the University of Texas at Austin, directs the sexual psychophysiology laboratory. David Buss, an expert on strategies of human mating, is author of The Evolution of Desire.

They draw on 1,006 interviews with women aged 18-86, and research on the physiology of arousal (everything from monitoring genital blood flow to studying women in singles bars).

Refreshingly, they blow out of the water the theory that women only have sex to procreate. Women's 237 "reasons" range from sex as a defence against infidelity to boosting self-confidence, as barter for gifts or housework and as a cure for a migraine. And yes, pleasure too – in our evolutionary past, orgasms were a "lure" to improve our chances of pregnancy.

But women can be Machiavellian. Meston and Buss find evidence of "mate poaching" and "jealousy evocation" tactics ("I decided to have sex with him to make my partner realise that other people wanted me").

My favourite reason is when Mr Acceptable Enough becomes Mr Can't Live Without. After repeated sex, we form a conditioned association. Soon just seeing him floods our brain with oxytocin, the cuddle hormone.

Musky aromas and resonant voices stir our desires, as do the faces of Antonio Banderas and George Clooney. Smell is hugely important (a sign of genetic compatibility); kissing is an emotional litmus test.

Meston and Buss offer more hard science than a book of Nancy Friday erotic fantasies. And the approach is feminist. "What sent Lisa screaming with desire could very well send Linda screaming out of the bedroom," they observe tartly.

I admit I approached Why Men Want Sex & Women Need Love with dread. But it's a readable, brutal analysis of how your brain chooses partners for you. Yes, we can rise above our inherited nature but in extremis our brains revert to default settings. And men and women want different things from sex – not better or worse, just different.

Men use their eyes to evaluate beauty; women use memory to assess a man's characteristics. Which is why we can remember every bloody detail of the third date – and they can't.

In love, women's testosterone levels rise, men develop more oxytocin. But when the "shagathon period" ends, we return to normal. The other problem is women no longer need silent providers. We want them to chat and have feelings. Bemused, men retreat into macho behaviour.

Why Men Want Sex is too keen to pardon the male "mono-tracking" brain. If we're equal but different, they can make an effort too. But it helps to know love is a mental disorder, like OCD. Romantic feelings are chemical responses in the brain – not the mystical meeting of souls.

I emerged with renewed respect for the "strong" women in my family who have kept the show on the road. Without them I wouldn't be here. "Women's mating desires have evolved because they led ancestral mothers to make wise choices," write Meston and Buss.