The Red Queen_ Sex and the Evolution of Human Nature - Matt Ridley [127]
This is something every parent knows. Despairingly they watch their son turn every stick into a sword or gun, while their daughter cuddles even the most inanimate object as if it were a doll. A woman wrote to the Independent newspaper on 2 November 1992 as follows: ‘I would be interested if any of your more learned readers could tell me why, from the time my twins could reach for toys and were put on a rug together with a mixed selection of “boys’ ” and “girls’ ” baby toys, he would inevitably select the car/ train items and she the doll/teddy ones.’
The genes cannot be denied. And yet, of course, there are no genes for liking guns or dolls, there are only genes for channelling male instincts into imitating males or female instincts into imitating female behaviour. There are natures that respond to some nurtures and not others.
At school, boys are fidgety, difficult, inattentive and slow to learn, compared with girls. Nineteen out of every twenty hyperactive children are boys. Four times as many boys as girls are dyslexic and learning disabled. ‘Education is almost a conspiracy against the aptitudes and inclinations of a school boy’, wrote psychologist Dianne McGuinness, a sentiment to which almost every man with a memory of school will raise a hearty cry of assent.17
But another fact begins to emerge at school. Girls are simply better at linguistic forms of learning, boys at mathematical and some spatial skills. Boys are more abstract, girls more literal. Boys with an extra X chromosome (XXY instead of the normal XY) are much more verbal than other boys. Girls with Turner’s syndrome (no ovaries) are even worse at spatial tasks than other girls, but just as good at verbal ones. Girls who were exposed to male hormones in the womb are better at spatial tasks. Boys who were exposed to female hormones are worse at spatial tasks. These facts have been first disputed and then actively suppressed by the educational establishment, which continues to insist that there are no differences in learning ability between boys and girls. According to one researcher, such suppression has done both boys and girls far more harm than good.18
And the brain itself begins to show strange differences. Brain functions become more diffuse in girls, whereas they take up specific locations in the heads of boys. The two hemispheres of the brain become more different and more specialized in boys. The corpus callosum, which connects the two, grows larger in girls. It is as if testosterone has begun to isolate the boy’s right hemisphere from the colonization by verbal skills from the left.
These facts are far too few and unsystematic to be regarded as anything more than hints of what actually happens, but the role of language acquisition must be critical. Language is the most human and therefore most recent of our mental skills – the one we share with no other ape. Language seems to come into the brain like an invading Goth, taking the place of other skills, and testosterone appears to resist this. Whatever actually happens, it is an indisputable fact that at the age of five, when they first arrive at school, the average boy has a very different brain from the average girl.
Yet, at five, the testosterone levels in the average boy are identical to those of the average girl, and a fraction of what they were at birth. The pulse of testosterone in the womb is a distant memory, and there will be little difference between the sexes in testosterone levels until the age of eleven or twelve. A boy of eleven is far more similar to a girl of the same age than he has been before or will be again. He is academically her equal for the first time and his interests are not so far apart. Indeed, there is one piece of medical evidence that at this age a person can still grow up to be, mentally, either a typical man or a typical woman, despite the hormonally induced differences of childhood.