Happy International Day of You, women of the world. Unfortunately it remains internationally respectable to argue that science has shown that men are inherently better at math and scientific pursuits than you are. This belief is based on the gender difference in scores on standardized tests—differences that seem to extend throughout the world, in many different types of society. Of course, it also has to be said that many different types of society discriminate against women, despite the world bestowing this whole day on you. Wouldn't it be great to have a straight-up comparison between a society that curtails women's opportunities and a more egalitarian one? Turns out it has been done, in this study, which was published a few months ago in the Proceedings of the National Academy of Sciences. The researchers found a typical male advantage on a spatial test in the more male-dominated group. But in the society where women were closer to equality with men, the gender difference did not exist.
The beauty of the study, in which 1,279 people were paid to solve a four-piece puzzle, is that the two societies are substantially alike except for the way they treat women. They both occupy the same region near the city of Shillong in Meghalaya State in northeast India. They make their livings in the same way and have the same income levels. A genetic analysis finds them to be closely related. But the Khasi are a matrilineal tribe, where family inheritance runs from mother to youngest daughter, while the Karbi are patrilineal, passing property from father to oldest son. Property is owned mostly by men, and women average fewer years of education than their male peers. Among the Khasi, though, women and men get an equal number of years in school, and men own no property.
Moshe Hoffman and his co-authors offered a decent sum (20 rupees) to those among their volunteers who could solve a spatial puzzle in less than 30 seconds. Among the patrilineal Karbi, men were 36 percent faster than women at doing this spatial task. Among the matrilineal Khasi, though, men were no faster than women.
As the authors note, this study doesn't disprove that there are no innate differences in ability. But it does show that culture matters, which means, I think, that it shows it is way too soon to claim that science has established that innate male-female differences explain the gap on tests between men and women. It is consistent with evidence from education research which suggests that immediate circumstances have a big impact on test performance: Those studies have found that male advantage in science and math tests can be made to go away by some simple interventions (for example, putting pictures of women in the textbook, or reminding women that they're good students).
Hoffman, M., Gneezy, U., & List, J. (2011). Nurture affects gender differences in spatial abilities Proceedings of the National Academy of Sciences, 108 (36), 14786-14788 DOI: 10.1073/pnas.1015182108