[NextGenderation]
*********************************************
http://www.nytimes.com/2005/01/24/science/24women.html?incamp=article_popula
r_1&pagewanted=print&position=
The New York Times
January 24, 2005
Gray Matter and Sexes: A Gray Area Scientifically
By NATALIE ANGIER
and KENNETH CHANG
When Lawrence H. Summers, the president of Harvard,
suggested this
month
that one factor in women's lagging progress in science
and mathematics
might be innate differences between the sexes, he
slapped a bit of
brimstone into a debate that has simmered for decades.
And though his
comments elicited so many fierce reactions that he
quickly apologized,
many were left to wonder: Did he have a point?
Has science found compelling evidence of inherent sex
disparities in
the
relevant skills, or perhaps in the drive to succeed at
all costs, that
could help account for the persistent paucity of women
in science
generally, and at the upper tiers of the profession in
particular?
Researchers who have explored the subject of sex
differences from every
conceivable angle and organ say that yes, there are a
host of
discrepancies between men and women - in their average
scores on tests
of quantitative skills, in their attitudes toward math
and science, in
the architecture of their brains, in the way they
metabolize
medications, including those that affect the brain.
Yet despite the desire for tidy and definitive answers
to complex
questions, researchers warn that the mere finding of a
difference in
form does not mean a difference in function or output
inevitably
follows.
"We can't get anywhere denying that there are
neurological and hormonal
differences between males and females, because there
clearly are," said
Virginia Valian, a psychology professor at Hunter
College who wrote the
1998 book "Why So Slow? The Advancement of Women."
"The trouble we have
as scientists is in assessing their significance to
real-life
performance."
For example, 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.
But throughout history, people have cited anatomical
distinctions in
support of overarching hypotheses that turn out merely
to reflect the
societal and cultural prejudices of the time.
A century ago, the French scientist Gustav Le Bon
pointed to the
smaller
brains of women - closer in size to gorillas', he said
- and said that
explained the "fickleness, inconstancy, absence of
thought and logic,
and incapacity to reason" in women.
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.
To further complicate the portrait of cerebral
diversity, new brain
imaging studies from the University of California,
Irvine, suggest that
men and women with equal I.Q. scores use different
proportions of their
gray and white matter when solving problems like those
on intelligence
tests.
Men, they said, appear to devote 6.5 times as much of
their gray matter
to intelligence-related tasks as do women, while women
rely far more
heavily on white matter to pull them through a ponder.
What such discrepancies may or may not mean is
anyone's conjecture.
"It is cognition that counts, not the physical matter
that does the
cognition," argued Nancy Kanwisher, a professor of
neuroscience at the
Massachusetts Institute of Technology.
When they do study sheer cognitive prowess, many
researchers have been
impressed with how similarly young boys and girls
master new tasks.
"We adults may think very different things about boys
and girls, and
treat them accordingly, but when we measure their
capacities, they're
remarkably alike," said Elizabeth Spelke, a professor
of psychology at
Harvard. She and her colleagues study basic spatial,
quantitative and
numerical abilities in children ranging from 5 months
through 7 years.
"In that age span, you see a considerable number of
the pieces of our
mature capacities for spatial and numerical reasoning
coming together,"
Dr. Spelke said. "But while we always test for gender
differences in
our
studies, we never find them."
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,
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. "We have no idea why
this should be so,"
said Almar Midvik Halldorsson, project manager for the
Educational
Testing Institute in Iceland.
Interestingly, in Iceland and everywhere else, girls
participating in
the survey expressed far more negative attitudes
toward math.
The modest size and regional variability of the sex
differences in math
scores, as well as an attitudinal handicap that girls
apparently pack
into their No. 2 pencil case, convince many
researchers that neither
sex
has a monopoly on basic math ability, and that culture
rather than
chromosomes explains findings like the gap in math SAT
scores.
Yet Dr. Summers, who said he intended his remarks to
be provocative,
and
other scientists have observed that while average math
skillfulness may
be remarkably analogous between the sexes, men tend to
display
comparatively greater range in aptitude. Males are
much likelier than
females to be found on the tail ends of the bell
curve, among the
superhigh scorers and the very bottom performers.
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.
For Dr. Summers and others, the overwhelmingly male
tails of the bell
curve may be telling. Such results, taken together
with assorted other
neuro-curiosities like the comparatively greater
number of boys with
learning disorders, autism and attention deficit
disorder, suggest to
them that the male brain is a delicate object,
inherently prone to
extremes, both of incompetence and of genius.
But few researchers who have analyzed the data believe
that men's
greater representation among the high-tail scores can
explain more than
a small fraction of the sex disparities in career
success among
scientists.
For one thing, said Kimberlee A. Shauman, a
sociologist at the
University of California, Davis, getting a high score
on a math
aptitude
test turns out to be a poor predictor of who opts for
a scientific
career, but it is an especially poor gauge for girls.
Catherine
Weinberger, an economist at the University of
California, Santa
Barbara,
has found that top-scoring girls are only about 60
percent as likely as
top-scoring boys to pursue science or engineering
careers, for reasons
that remain unclear.
Moreover, men seem perfectly capable of becoming
scientists without a
math board score of 790. Surveying a representative
population of
working scientists and engineers, Dr. Weinberger has
discovered that
the
women were likelier than the men to have very high
test scores. "Women
are more cautious about entering these professions
unless they have
very
high scores to begin with," she said.
And this remains true even though a given score on
standardized math
tests is less significant for women than for men. Dr.
Valian, of
Hunter,
observes that among women and men taking the same
advanced math courses
in college, women with somewhat lower SAT scores often
do better than
men with higher scores. "The SAT's turn out to
underpredict female and
overpredict male performance," she said. Again, the
reasons remain
mysterious.
Dr. Summers also proposed that perhaps women did not
go into science
because they found it too abstract and cold-blooded,
offering as
anecdotal evidence the fact that his young daughter,
when given toy
trucks, had treated them as dolls, naming them "Daddy
truck" and "baby
truck."
But critics dryly observed that men had a longstanding
tradition of
naming their vehicles, and babying them as though they
were humans.
Yu Xie, a sociologist at the University of Michigan
and a co-author
with
Dr. Shauman of "Women in Science: Career Processes and
Outcomes"
(2003),
said he wished there was less emphasis on biological
explanations for
success or failure, and more on effort and hard work.
Among Asians, he said, people rarely talk about having
a gift or a
knack
or a gene for math or anything else. If a student
comes home with a
poor
grade in math, he said, the parents push the child to
work harder.
"There is good survey data showing that this disbelief
in innate
ability, and the conviction that math achievement can
be improved
through practice," Dr. Xie said, "is a tremendous
cultural asset in
Asian society and among Asian-Americans."
In many formerly male-dominated fields like medicine
and law, women
have
already reached parity, at least at the entry levels.
At the
undergraduate level, women outnumber men in some
sciences like biology.
Thus, many argue that it is unnecessary to invoke
"innate differences"
to explain the gap that persists in fields like
physics, engineering,
mathematics and chemistry. Might scientists just be
slower in letting
go
of baseless sexism?
C. Megan Urry, a professor of physics and astronomy at
Yale who led the
American delegation to an international conference on
women in physics
in 2002, said there was clear evidence that societal
and cultural
factors still hindered women in science.
Dr. Urry cited a 1983 study in which 360 people - half
men, half women
-
rated mathematics papers on a five-point scale. On
average, the men
rated them a full point higher when the author was
"John T. McKay" than
when the author was "Joan T. McKay." There was a
similar, but smaller
disparity in the scores the women gave.
Dr. Spelke, of Harvard, said, "It's hard for me to get
excited about
small differences in biology when the evidence shows
that women in
science are still discriminated against every stage of
the way."
A recent experiment showed that when Princeton
students were asked to
evaluate two highly qualified candidates for an
engineering job - one
with more education, the other with more work
experience - they picked
the more educated candidate 75 percent of the time.
But when the
candidates were designated as male or female, and the
educated
candidate
bore a female name, suddenly she was preferred only 48
percent of the
time.
The debate is sure to go on.
Sandra F. Witelson, a professor of psychiatry and
behavioral
neurosciences at McMaster University in Hamilton,
Ontario, said biology
might yet be found to play some role in women's
careers in the
sciences.
"People have to have an open mind," Dr. Witelson said.
____________________________
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
