Nature and sex redefined – we have never been binary

20.02.2015 14:46

A recent article in Nature claims that
biologists ‘now think’ that sex is not a
binary feature for human beings – rather
than being simply male or female, there
are various kinds of sex, such as
chromosomal sex or hormonal sex, and all
of us exist across several spectrums of
sexual identity.
Two sex; five sex; nine sex
The claim that we are non-binary is well
evidenced, but the claim that this is what
biologists ‘now think’ seems to ignore
much of the history of sex and gender
research. This is made clear by the very
first comment on the article, signed ‘Anne
Fausto-Sterling’. Fausto-Sterling is a
pioneering researcher into sex and gender
identities, and published controversial
work in the early 1990s suggesting that
there were at least five different ways of
measuring sex – a publication which is not
mentioned at all in the Nature article.
The scientific scepticism of ‘binary’ sex –
that is the idea that there are men and
women and they can be clearly
distinguished – started even earlier. In
1968 the Journal of the American Medical
Association carried an article by biologist
Keith L Moore, listing nine different
components of someone’s sexual identity:
external genital appearance, internal
reproductive organs, structure of the
gonads, endocrinologic sex, genetic sex,
nuclear sex, chromosomal sex,
psychological sex and social sex.
It’s possible to design tests for many of
these kinds of sex, but none of them
provide a convenient ‘male or female’
binary answer. Results will always depend
on averages, on statistical norms, or on
arbitrary cut-off points, and there will
always be people who appear both male or
female (or neither) when all nine kinds of
sex are considered. Further, what science
cannot do is tell us which of these tests is
the best measure of sex, or which gives us
our ‘true’ identity – that entirely depends
on what we want to do with the results,
why we’re testing, and our cultural
attitudes towards sex and gender (gender
being the psychological and social aspects
of sexual identity).
(Barr) Bodies of Evidence
Moore wrote his article in 1968 specifically
to criticise one form of sex testing: the tests
that were being used in international sport
to decide whether athletes were eligible to
compete as women. Sport is often an arena
that absolutely insists that human beings
come in only two forms, male or female,
and has spent around 80 years trying to
find an objective scientific test that will
prove that this is the case. So far it has
This failure came as no surprise to many of
the scientists working in genetics, or
endocrinology, or other areas of the study
of sex and gender. At least as early as the
1930s it was scientifically understood that
some aspects of biological sex and gender
identity might not match in individuals,
and surgery and hormonal treatments
were used to help people create stable
identities . There were several high-profile
cases of transgendered athletes in the
1930s and ‘40s , so the idea that sexual and
gender identity might be fluid rather than
fixed was discussed in the popular press as
well as in scientific journals. These stories
were part of the reason international
sports organisations began to introduce
stricter eligibility rules for women’s sports
in the 1940s.
Moore was intimately familiar with these
tests, as he was a co-developer of the one
the International Olympic Committee (IOC)
used for nearly 25 years. Moore was the
PhD student of Canadian scientist Murray
Barr, who in 1949 published (in Nature as
it happens) the discovery of the ‘Barr
body’. This is a chromosomal artefact
caused by the inactivation of the second X
chromosome in a cell ; as it is relatively
easy to visualise it is sometimes used as a
rough and ready indicator of ‘femaleness’
in mammals.
The Barr body test was the first
standardized scientific test for sex used in
international sport, replacing the
unpopular ‘naked parades’ in 1968. But by
the time the IOC introduced the Barr body
test, it was already being condemned as
unreliable as a proxy for sex by Barr and
his fellow researchers, including Moore,
who said
Females have been declared ineligible for
athletic competition for no other apparent
reason than the presence of an extra
chromosome…[these tests] cannot be used as
indicators of ‘true sex’
Why do we need the binary?
I’ve pointed out elsewhere that the
problem with sex testing for sports is that
none of the ‘kinds’ of sex correlate
perfectly with sporting ability , so any test
will exclude competitors with no physical
advantage. Meanwhile lots of other genetic
and physiological variations - such as
height - confer advantages on some lucky
competitors, and yet we make no effort at
all to segregate these athletes in the name
of ‘fairness’. Scientists always understood
the limitations of sex tests, even if sports
administrators struggled to accept them: in
particular there was Finnish geneticist
Albert de la Chappelle, who fought against
the IOC’s sex testing regime of the 1980s,
promoting a more complicated way of
determining eligibility that would
consider hormonal, physiological and
psychological sexual identity.
Although attitudes towards people who
identify as transgender or intersex, or
simply ‘non-binary’, have not always been
sympathetic, there has never been
scientific (or philosophical, or sociological)
consensus that there are simply two
human sexes, that they are easily (and
objectively) distinguished, and that there
is no overlap between the two groups. Nor
have they agreed that all of us are ‘really’
one sex or the other even if bits of our
bodies or our identities don’t entirely
match that sex. You can examine someone’s
genitals, their blood, their genes, their
taste in movies, the length of their hair,
and make a judgement, but none of these
constitute a universal or objective test for
sex, let alone for gender.
When groups, whether in sport or
elsewhere, turn to scientific definitions to
try to exclude some people from the
category of ‘woman’, it is worth
remembering this fact: scientists have
never agreed on which kind of sex really
matters to our identities, or to our right to
call ourselves men, or women, or neither,
or both.