(BQ) Part 2 book “The minder brain” has contents: The sexual brain, bonding, motherhood and love, the brain goes to war, the rhythm of life, the brain breaks down, individualit. | b459-ch08 5/7/07 16:29 FA Page 200 Chapter 8 The Sexual Brain Nobody, the American scientist Frank Beach once memorably declared, ever died from lack of sex. Beach made substantial contributions to our understanding of the way that hormones control sexual behaviour, but in this case he was articulating a real problem. If sex is not essential for the individual, how does the brain make it into an imperative demand? The ‘why’ is rather easier: if we did not bother with sex, there would be no human race to think about it. But sex is a biologically and socially costly business. We spend a great deal of time doing things that is related to it, or to parenthood, the biological consequence and rationale for sexual behaviour. But the payoff is less for the individual than for his/her species. So it is a different kind of demand from the business of daily survival, though the process of reproduction may have vast influence on survival itself. This is the reason that the brain uses many of the mechanisms to regulate sex that we might otherwise think of in connection with more obvious physiological demands such as getting enough food and water. We have a brain that not only ‘knows’ how to make us focus on sex when it matters, but also ensures that we do, not at all for our sake but for the preservation of future generations. The brain is being altruistic, but in so doing, it enables Darwinian selection. If there was no sexual behaviour, no urge to procreate, no brain mechanisms for selecting a mate and for seeing off the competition, no care of the young so that enough survived, then there would be no genetic material on which selection could act. And sexual selection (who mates with whom), the second Darwinian mechanism, relies totally on the brain. That means we need a brain that not only makes us breed, but makes the ‘right’ choice about with whom we breed. 200 b459-ch08 5/7/07 16:29 FA Page 201 The Sexual Brain 201 Sexual Selection and Competition This .
