Sex is a divisive topic, loaded with moral weight and the scientific stamp of truth. The word ‘sex’ is of French (sexe) and Latin (sexus) origins, with sexus connected to secare (to cut/divide) and seco (half of). It is no surprise, then, that the sex binary is so firmly rooted in Euro-American thought, along with many others (think body and mind, nature and culture). It underpins and naturalises gendered divisions of labour through, for example, the notion of women as the weaker sex. Language mirrors the distinction between male and female, as in the way we talk about the sexes as ‘opposite’, and throughout life we are encouraged to think in binary terms about this central aspect of our existence.

While these gendered binaries play out in social life in reasonably clear ways, they also seep into places conventionally seen as immune to bias. For example, they permeate sex science. In her paper ‘The Egg and the Sperm’ (1991), the anthropologist Emily Martin reported on the ‘scientific fairy tale’ of reproductive biology. Searching textbooks and journal articles, she found countless descriptions of sperm as active, independent, strong and powerful, produced by the male body in troves; eggs, in contrast, were framed as large and receptive, their actions reported in the passive voice, and their fate left to the sperm they might or might not encounter. Representations in this vein persisted even after the discovery that sperm produce very little forward thrust, and in fact attach to eggs through a mutual process of molecular binding. Martin’s point? That scientific knowledge is produced in culturally patterned ways and, for Euro-American scientists, gendered assumptions make up a large part of this patterning.

In Gender Trouble (1990), the feminist theorist Judith Butler argues that the insistence on sex as a natural category is itself evidence of its very unnaturalness. While the notion of gender as constructed (through interaction, socialisation and so on) was gaining some acceptance at this time, Butler’s point was that sex as well as gender was being culturally produced all along. It comes as no surprise to those familiar with Butler, Martin and the likes, that recent scientific findings suggest that sex is in fact non-binary. Attempts to cling to the binary view of sex now look like stubborn resistance to a changing paradigm. In her survey paper ‘Sex Redefined’ (2015) in Nature, Claire Ainsworth identified numerous cases supporting the biological claim that sex is far from binary, and is best seen as a spectrum. The most remarkable example was that of a 70-year-old father of four who went into the operating room for routine surgery only for his surgeon to discover that he had a womb.

Early in its development, an embryo is sexless, able to move toward male or female characterisation. ‘The identity of the gonad,’ writes Ainsworth, ‘emerges from a contest between two opposing networks of gene activity.’ Different genes guide the gonad to turn into ovaries or testes, or, in the case of the RSPO1 gene, ovotestis, a hybrid of the two. Equally interesting are mouse studies that indicate that the state an individual’s gonads take is not just set early in life and fixed from that moment; rather it could require ongoing maintenance across a lifetime.

The picture this paints is of sex as a composite, potentially shifting over time. Sex is at the same time genetic, hormonal and morphological. All of these different manifestations of sex layer onto each other, so people might go their whole lives without knowing that they have cells or even organs of the ‘opposite’ sex.

Ainsworth raises the important point that while multiple gender identities are gaining social acceptance, and science is lending its legitimating powers to the idea of a sex spectrum, legal systems remain clumsy and ill-equipped to cope with such thoughts. Feminists and lesbian, gay, bisexual, queer and transgender scholars and activists have known this for some time, and have offered rich alternatives for thinking through law, sex and gender. Meanwhile, social scientists and historians have looked to other times and places to explore how sex and gender might be conceptualised.

In his book Making Sex (1990), Thomas Laqueur argues that some pre-modern Europeans recognised only one sex, on which they imposed two possible genders. The female body, from this perspective, was a mere inversion of the male. Both were characterised by a penis, which in women was simply interior to man’s exterior. As the anthropologist Rosalind Morris writes in ‘All Made Up’ (1995), Laqueur’s work ‘forces readers to acknowledge that gender dichotomies can be imagined in a variety of ways, none of which are reducible to the absolute oppositions that contemporary biology posits in the so-called natural body’. It also reminds us that the ‘sex spectrum’ is itself rooted in Euro-Western gender dichotomies, with male and female providing the framework upon which the new sex science is mapped.

In parts of Melanesia, the cluster of islands scattered through western Oceania, a person is thought to be made up of other, gendered, parts of people: their father’s bone, their mother’s blood. As such, they are always a composite of male and female. Though people here can resemble ‘men’ or ‘women’, ‘in gender terms, the single sex figure will have parts or appendages “belonging” to the opposite sex’, writes Marilyn Strathern in The Gender of the Gift (1988). Moreover, these parts might not always be of one gender or the other – they change according to circumstance. Relations and exchanges provoke gender to emerge differentially between people, over time.

This ‘dividual’ understanding of personhood is framed as a counterpoint to the individualism so taken for granted in the Euro-American world; dividualism acknowledges a form of existence in which the human person is not a bounded individual but an interpellated part of the social whole. That person’s existence is continually brought into being through interactions and exchanges with others. With such an understanding of personhood, sex becomes less of a totalising phenomena.

In the Papua New Guinean highlands, the Kamea see kinship not in terms of genes and heredity, but in social ties with familial obligations elicited through exchange, writes Sandra Bamford in Biology Unmoored (2007). For Kamea, a mother’s and father’s bodily substances struggle in utero, and the child’s ultimate sex is determined by the stronger. For the first five years of life, male and female children are treated as essentially the same, and referred to as imia (roughly, child) without any gendered qualification. Bamford writes: ‘The difference between “male” and “female”, or “brother” and “sister”, are not taken to be innate, but have to be created against an ungendered backdrop of “one-bloodedness”, which furnishes first and foremost an original field of sameness.’ This sameness drops away when a woman marries or a man undergoes his initiation rites. Through these rituals, people become fully reproductive beings. For the Kamea, biology is not meaningful in and of itself, but is made so through social processes.

Looking to other times and to other cultures, we are reminded that sex is to some degree produced through the assumptions we make about each other and our bodies, and the meanings we derive from our relationships. Now that our science is moving towards consensus on sex as a spectrum rather than a simple male/female binary, it is time to start casting around for new ways of thinking about this fundamental aspect of what we are. Historical and anthropological studies provide a rich resource for re-imagining sex, reminding us that the sex spectrum itself is rooted in Euro-Western views of the person and body, and inviting critical engagement with our most basic biological assumptions.

Courtney Addison & Samuel Taylor-Alexander

This article was originally published at Aeon and has been republished under Creative Commons.