1 The Data of Biology

      We … often behave and talk as if the sexes are categorically different: men like this, women like that. … In toy stores sex-segregated product aisles … assume that a child’s biological sex is a good guide to what kinds of toys will interest them. … When we think of men and women in this complementary way it is intuitive to look for a single powerful cause that creates the divide between the sexes. … Wouldn’t it make sense if testosterone … makes men like this, while its minimal presence in females helps to make women like that? … This is Testosterone Rex: that familiar, pervasive and powerful story of sex and society. Weaving together interlinked claims about evolution, brains, hormones and behavior, it offers a neat and compelling account … [But] Testosterone Rex is wrong, wrong, and wrong again. (Fine 2017: 17–22)

      The idea of the male brain and the female brain suggests that each is a characteristically homogenous thing and that whoever has got a male brain, say, will have the same kind of aptitudes, preferences and personalities as everyone else with that ‘type’ of brain. We now know that is not the case. We are at the point where we need to say, ‘Forget the male and female brain; it’s a distraction, it’s inaccurate.’ … It is now a scientific given … that the brain is moulded from birth onwards and continues to be moulded through to the ‘cognitive cliff’ in old age when our grey cells start disappearing. So out goes the old ‘biology is destiny’ argument. (Gina Rippon, quoted in Fox 2019)

Sexed/gendered difference

In contemporary discussions of sexed differences, there is a renewed search for a determining factor which both divides us clearly into men and women and fixes the distinguishing features of each category. In favour again are sex hormones, particularly amounts of testosterone (Fine 2017). The other favourite contender is the brain (Rippon 2019). In many theories, the quantity of testosterone is thought to determine the development of the brain. With Fine and Rippon, we hope to challenge the assumptions informing such claims.

The concern of this book is to explain how we end up as sexed human beings, with self- and other-assigned categorizations as men or women, male or female (or trans men or women, or intersex, or non-binary), with which we may be happy or unhappy, but which, either way, is one of the defining features of both our subjectivity and our social positionality. As we noted in the introduction, this area of investigation is now termed ‘gender theory’, and the term ‘gender’ has come, in everyday usage, to signal such sexed positionality. Under discussion is the status of our categories of sexed difference – categories that may be marked by use of the terms ‘male’ or ‘female’ or ‘man’ and ‘woman’. There is a complexity here considering what terminology to use. ‘Male’ and ‘female’ are employed throughout the animal and, to some extent, plant kingdoms and so have more claim to be categories whose identifying criteria are fixed by biological science, criteria which may vary for different scientific purposes. But in everyday practice, for humans, we do not make a distinction between, for example, being female and being a woman. Here we are concerned with these categories as used in everyday interactions to characterize ourselves and others we encounter. What we are exploring is the (most common) binary division of people into male and female, a categorization which becomes fundamental to people’s sense of their identity, frames the way they are seen by others, and carries with it associated expectations of patterns of behaviour and social positionality. The division into male and female bodies, men and women, is linked in a complicated way to a division into masculine and feminine people – where masculinity is a set of psychological and behavioural traits that are considered particularly appropriate to those classified as male, and feminine traits appropriate to those classified as female. The link between being male and masculinity and being female and femininity is a normative one. It is what is supposed to happen but is often deviated from. And, indeed, there is never an absolute coincidence. In investigating how we end up as men and women, or as non-binary, we are therefore investigating a phenomenon that has bodily, psychological, behavioural and social dimensions. It also has mythical or imaginary ones. For we are surrounded by stories and images which convey meanings about what it is to be a woman or man which interact with the other strands of individuation. In this first chapter, we will be exploring the contribution made by what Beauvoir (see chapter 4) calls the data of biology.

      In the introduction we introduced the notion of gender essentialism, the suggestion that there is some fixed set of conditions which determine whether we are male or female, men or women. Those who adopt gender essentialist positions most commonly anchor them in biology. It is assumed that biology will provide us with the answer to the questions of what determines whether a person is male or female, man or woman, or maybe some combination of both. In this book we resist the claim that biology is determining in this way. But to resist this claim is not to make our biological bodies irrelevant to the complex story of how we end up gendered. They are part of the picture but not the whole of it. Moreover, our biological bodies are themselves infinitely complex, open and changing, susceptible to multiple understandings, and interwoven with our wider material and social environments in ways that render it impossible to isolate the contributions they make from other aspects of our becomings (Rippon 2019).

Sexed categories as natural kinds

Sex difference research has been a continually thriving area for at least the last two hundred years (Cameron 2007; Fine 2012). There are two fundamental assumptions underlying this work which will be scrutinized separately here. First is the assumption that the binary division of bodies into male and female is part of the natural order of the world. Within this assumption, facts about our biology provide an explanatory grounding for our sexed categories in a way that makes a division into male and female a recognition of objective facts of nature, which, in some sense, demand attention. Objective here means having a unifying factor that is independent of our practices of classification. There are differing accounts of what the most basic biological determinants of this binary division are, and research into the biology of sexed difference explores the roles played by, for example, visible morphology, brains, hormones and chromosomes. But such exploration takes place within an assumption that the sexed kinds ‘male’ and ‘female’ are biological kinds, reflecting a naturally occurring grouping of properties that have important causal effects, particularly within the biology of reproduction – for example, ‘the ability to make a distinctive contribution to reproduction – i.e. [for females] to gestate, give birth to and breast-feed babies’ (Stone 2007: 44). We will return to evaluate these claims below.

Psychological and behavioural sex differences and their biological anchorage

      The second key assumption of much scientific work on sex differences is that the assumed division into male and female bodies is accompanied by other differences, associated psychological and behavioural dispositions, which have consequent effects on social positionality. There is, of course, disagreement as to what range of responses are supposed to be conditioned by sex differences in this way. Recurring themes concern greater aggression and competitiveness in men and greater nurturing qualities in women, greater spatial and