Science in the Summers-time

Following on the debate sparked by Larry Summers' recent comments, the Times drops some science on innate versus acquired differences. Some interesting factoids:

Neuroscientists have shown that women's brains are about 10 percent smaller than men's, on average, even after accounting for women's comparatively smaller body size... Overall size aside, some evidence suggests that female brains are relatively more endowed with gray matter - the prized neurons thought to do the bulk of the brain's thinking - while men's brains are packed with more white matter, the tissue between neurons.

In adolescence, though, some differences in aptitude begin to emerge, especially when it comes to performance on standardized tests like the SAT. While average verbal scores are very similar, [American] boys have outscored girls on the math half of the dreaded exam by about 30 to 35 points for the past three decades or so. Nor is the masculine edge in math unique to the United States. In an international standardized test administered in 2003 by the international research group Organization for Economic Cooperation and Development to 250,000 15-year-olds in 41 countries, boys did moderately better on the math portion in just over half the nations. For nearly all the other countries, there were no significant sex differences. But average scores varied wildly from place to place and from one subcategory of math to the next. Japanese girls, for example, were on par with Japanese boys on every math section save that of "uncertainty," which measures probabilistic skills, and Japanese girls scored higher over all than did the boys of many other nations, including the United States. In Iceland, girls broke the mold completely and outshone Icelandic boys by a significant margin on all parts of the test, as they habitually do on their national math exams.

Among college-bound seniors who took the math SAT's in 2001, for example, nearly twice as many boys as girls scored over 700, and the ratio skews ever more male the closer one gets to the top tally of 800. Boys are also likelier than girls to get nearly all the answers wrong.