Boys from upper- and working-class families consistently outperfomred their female counterparts on both spatial relations tasks . . . No sex difference in spatial scores appeared among kids from poor families, and both boys and girls scored lower than their counteparts in he other two groups did. As the investigators expected, no sex difference emerged in sentence comprehension in any of the groups . . .in each economic group, especially high score on spatial relations task were usually boys . . . Similarly, earlier studies have found that more boys than girls achieve extremely high scores in mathematics.
This is explosive stuff that won a President of Harvard University a heap of oppumbrium. Many studies have shown gender differences on spatial relations test, but this is the first to link those differences to family income, suggesting some role for nuture in this difference. Many people would like to believe that differences in spatial relations test performance and math performance between men and women is simply a product of discriminatory child rearing. I don't believe it. Why?
1. School likely doesn't play a strong part in these results. We are talking about second graders, not high school students.
2. The only place where we don't see boys having an edge over girls is among poor boys and girls who don't score extremely high on spatial relations tasks. The theory suggested by the researchers, which seems plausible, is that boys are naturally more likely to have strong spatial relations abilities, but that the deprivation of poverty (including in many cases poor access to toys and few opportunties to explore their neighborhoods) stunts that potential in both boys and girls.
3. There is no good reason to believe that poor families are markedly less gender biased in the way that they raise their children than working class or wealtheir families. Indeed, our intuition would be that higher income parents would deliberately avoid gender stereotypes, while poor families wouldn't care. Of course, on the other hand, one could look at the data and note that poor families are much more likely to be headed by a single mother than more affluent families, and that seeing a mother in a head of household role and not having a father in the family could impact gender biases in child rearing.
4. While my own experience is anecdotal, as a father of a girl and a boy, I was stunned at just how early boys and girls start demonstrating very gender stereotyped behavior, without an conscious effort on the part of either my wife or myself, to establish those stereotypes. At ages 6 and 4, there are already immense gender typical differences between my son and daughter, and those differences started to manifest at least as early as one year of age, when they first started to talk. My daughter, at that age, was facinated by animals. My son, at that age, hardly noticed animals was already obsessed with machines (cars, trains, trucks, construction equipment). The list for each is lengthy, but, while it is only a single case, it does have persausive power.
5. I am aware of, although I can't easily locate a citation to, studies that seem to indicate that spatial relations ability is something that we inherit from our mothers, which is a dominant gene in boys, but far less likely to express itself (perhaps a recessive gene, perhaps something else) in girls.
6. I have also seen studies (again, these are from my pre-internet days) which indicate that spatial relations ability along with musical ability, tend to be some of the earliest maturing aptitudes, with adult levels of aptitude typically reached prior to the first grade, which would indicate a very limited time period in which nuture as opposed to nature could play a role. (In contrast, the same studies show that reasoning ability has usually reached adult levels in women at about puberty, and in men by the time they graduate from college).
7. The mathematics performance of boys and girls starts to see the great disparities around the time they enter high school. This also happens to be around the time that mathematics goes from being far more abstract, to being far more spatial relations oriented (in subjects like geometry, trig and calculus).
8. I am aware of another interesting spatial relations study that looked at sense of direction in men and women, and in particular tracked women's menstrual cycles at the same time. The study found that during their menstruation, men and women performed equally well on sense of direction tasks, while men greatly out performed women who were at peak fertility near ovulation at those same tasks.
Science News this week reports, based on the November 1, Proceedings of the National Academy of Sciences, another similar study that found that even women with no apparent symptoms of PMS had more negative reactions to words presented to them in a study on the eve of their periods, than they did at other parts of the menstrual cycle. Likewise, studies have shown "nearly 80 percent of epileptic women have more seizures than usual during the phase of the menstrual cycle when their blood concentration of progesterone declines and that of estrogen increases. Other studies showed that women with a condition called premenstrual dysphoric disorder experience severe anxiety and depression during the same phase." So, the study on sense of direction may not be a freak study.
This kind of phenomena would dramatically impede learning many spatial relations oriented subjects because subjects like mathematics and physics and chemistry are all highly sequential, and a tendency to stumble in those fields for a few days a month, when the subjects are usually taught over an extended period like a semester or year, makes that pace problematic for girls.
9. The fall out from the passage of laws banning gender discrimination in both educational institutions and almost all types employment is suggestive. For example, the percentage of law students who are women has gone from about 2% to a majority since the 1970s, producing a similarly dramatic shift in the gender make up of younger lawyers. In constrast, the change in the percentage of women who are engineers or physicists has been far more modest.
10. Given the scientific literature that precedes this study, and its design (incorporating both spatial and non-spatial measures), it is hard to argue either that the girls received inferior upbringing overall, or that
This doesn't mean that there aren't any women who have a knack for spatial relations. Boys outnumber girls among high performers on those tests, but they aren't absent from the group of high performers entirely. One of the most talented math majors at Oberlin College while I was there was a woman. There are certainly great women in science. But, probability and individual possibility are different things.