THE ROUGH GUIDE TO PSYCHOLOGYmen than women tend to display either extremely poor or extremely
strong ability in a subject. Female performance, by contrast, tends to
clump much more around the average. Consistent with this, conditions
like autism and ADHD are far more common in boys and men (in fact, a
popular theory is that autism is the manifestation of a having an extreme
male brain; see p.318).
Innate or culturally determined?
Gender feminists have argued that, rather than being innate, the
behavioural differences we see between boys and girls are the result
of socialization. By this account, boys like fighting and guns, and girls
like chatting and dolls, because they were brought up in a culture that
impressed those choices and dispositions upon them. This view, while
popular, doesn’t stand up to much objective scrutiny.
Consider a 2008 study by Kim Wallen and co-workers at Emory
University in Atlanta. Because it’s tricky to separate out biological and
cultural effects with human children, these researchers looked at gender-
related toy preferences in our close relative, the macaque monkey, in
whom cultural influences on play are absent. Like human boys, male
macaques were fussier than their female counterparts, tending to play
much more with wheeled toys (taken to be masculine) than cuddly toys
(feminine), given the choice of both. The female macaques, by contrast,
didn’t show a preference between the two, with the consequence that
they played with the cuddly toys more and the wheeled toys less than the
males did. The findings don’t rule out the role of societal influences on
children’s toy preferences, but they provide strong evidence for the part
played by biology.
Perhaps the most powerful evidence against the idea that gender iden-
tity is purely learned is a 2004 paper by William Reiner and John Gearhart
at John Hopkins University, in which they assessed sixteen boys from the
age of five to sixteen years who had been born with their penis missing – a
rare condition known as cloacal exstrophy. Fourteen of these boys were
raised from birth as if they were girls, even to the extent of having further
sex-change surgery. Despite this, eight of these fourteen declared them-
selves male during the course of the study, and all sixteen participants
were judged to have moderate to strong interests typical of males.
Related to this is the story of David Reimer, a Canadian man whose
penis was destroyed in a botched circumcision operation when he was
eight months old. Reimer was brought up as a girl and renamed Brenda,