Why Are Men Hopeless? It's All in the Mind New Research Claims the Development of Our Behaviour Is Mirrored in the Animal Kingdom, Writes Jerome Burns
Burns, Jerome, The Independent (London, England)
WHY do human males have such relatively big penises? Why do human females, almost uniquely among mammals, become infertile in middle age? Why are men, generally, more promiscuous than women? These are the sort of almost child-like questions that fascinate American writer and scientist Jared Diamond.
Such questions demand what are known as "ultimate causal explanations" - religion used to offer such answers along the lines of "because God made us that way" - but nowadays evolutionary biology is seen as a more useful source. So in his book Why is Sex Fun? (Phoenix, pounds 5.99) Diamond begins by looking at animal sexual behaviour as a way of uncovering why ours is so different.
One of the stars of his new book is the female spotted sandpiper who is as sexually predatory as the most randy alpha male primate. She will pursue the smaller males for miles, have sex and then ensure no female rivals mate with them. When the eggs are laid her role reversal is complete because the males incubate and guard the chicks, while she goes on another sexual spree. Nature emerges in this sort of account as a blind banker, ensuring, through the ruthless operation of genes, that all behaviours are subject to the disciplines of "profit and loss", "return on investment" and "energy costs". Applying these principles to human sexual behaviour allows Diamond to answer some of his questions. The menopause, for instance, turns out to be a logical response to a number of "cruel facts". "At first sight it's a real puzzle because it looks as though human females have evolved a physical trait that cuts down their chances of reproducing" he says. "But it makes perfect sense in light of certain unique human features, like the foetus's large head that makes childbirth very dangerous and the long period that the child needs caring for." It turns out that its a better bet to protect your existing investment in children than to risk dying, and so reducing their chances of survival, by trying for another one. A critique of applying what might be called the "heron factor" to humans is to say our intelligence puts us in a different league. We have culture and that makes a difference. "Of course you can't understand human behaviour without considering culture" Diamond admits "but the menopause isn't cultural and something like marriage is unusual among primates yet it's found in all societies, so culture can't explain that either. …