like Rossi (1977) who consider that,
It is the task of feminism to enable women to get back in touch with their biologically given essence by, among other things, persuading society to construe and value femininity and female biology equally with masculinity and male biology.
(Sayers 1982, p. 147)
Evolutionary theories about human behavior are still strong although the term sociobiology has largely fallen out of use and has been replaced by a number of offshoots such as evolutionary anthropology and evolutionary psychology. Although it is hard to find any proof for hypotheses about sex differences having their origins in cave life, the idea that our basic human propensities are laid down in our genes is still current, typified in this century by the popularity of the work of psychologists like Pinker (2002) and philosophers like Dennett (2003). Commitment to evolutionary and genetic determinism is still strong though challenged by the rise of areas such as epigenetics which examine the ways in which the environment can alter the expression of genes, once thought to be entirely impervious to external influences.
Hormones
Hormones have been a longstanding preoccupation of sex difference theorists. As with other strands of biological determinism, hormones have been resurrected in the twenty‐first century and are now a focus for contemporary brain scientists. Since the discovery of hormones and the fact that hormones act differently in males and females, hormones have been seen as an explanation for observed sex differences and indeed for the particular nature and psychology of women. Fausto‐Sterling was one of the first scientists to offer a resounding critique of theories purporting to show how women were in the grip of their hormones in her book Myths of Gender: Biological Theories about Women and Men, which was first published in 1985 and revised in 1992. She notes that,
some modern psychologists and biologists suggest that women perform more poorly than do men on mathematics test because hormonal sex differences alter male and female brain structures; and many people believe women to be unfit for certain professions because they menstruate. (1992[1985], p. 93)
Fausto‐Sterling examines the literature on the effects of menstruation and menopause on female behavior and finds evidence for significant negative effects resoundingly lacking. She comments on “the morass of poorly done studies on menstruation and menopause” (1992[1985], p. 121) but is heartened by the new research that rejects a traditional misogynistic medical model perspective, which positions women's hormones as toxic and abnormal, and instead situates the experience of menstruation and the menopause in their social contexts (e.g. Beyene 1992). Fausto‐Sterling also examines the evidence for sex differences in aggression. She points out that there is “no clear cut evidence to show that different testosterone levels in adult men and women result in differences in aggression” (1992[1985], p. 141). In fact there is very little evidence for a relationship between circulating hormones such as estrogen and testosterone and any human behavior. Given this reality, researchers often resort to arguments based on the action of fetal androgens on the brain, since the fact that fetal androgens are involved in the establishment of biological sex is incontrovertible. Some neuroscientists and endrocrinologists argue that sex hormones continue to act on the brain throughout life (McEwen and Milner 2017). However, the evidence that fetal hormones shape the human brain for life in a sex‐differentiated manner or that circulating sex hormones have a direct impact on the behavior of adult males and females is weak (Fine 2017).
Brains
Differences in male and female brains have been the focus of attention since the absolute difference in brain size was noted. At first the preoccupation was with the fact that female brains are smaller and therefore, it seemed safe to conclude, less competent (Tuana 1993). But the autopsies of the brains of famous men revealed that they might well have had a brain smaller than that of the average women and it also became clear that there was no correlation between intelligence and the size of the brain (Russett 1989). In general the focus moved to the way brains function rather than their size, although recently neuroscientists have shown an interest in examining and theorizing sex differences in the size of brain structures and in absolute size. For example, Grabowska speculates that there are “compensatory mechanisms in females that enable their smaller brains to work as effectively as male brains” (2017, p. 211).
The history of the study of the brain and the nervous system is a very long one but the rise of contemporary neuroscience is seen as a feature of the early 1980s, propelled by recent advances in molecular biology and brain imaging (such as Positron Emission Tomography (PET) scanning and Functional Magnetic Resonance Imaging (fMRI)). Neuroscience has become one of the most feted and well‐funded scientific disciplines, given considerable power and credibility within academia and in the public imagination. President George Bush declared the 1990s the Decade of the Brain in order to “enhance public awareness of the benefits to be derived from brain research.” Leaning on both evolutionary theory and research on hormones, as well as developments in the brain sciences, numerous publications since the 1980s, from both social and natural scientists, have promoted the view that the brains of men and women are different. One of the first books to gain prominence was Brain Sex by Moir and Jessel, published in 1989. They assert that,
Six or seven weeks after conception … the unborn baby “makes up its mind” and the brain begins to take on a male or female pattern. What happens at that critical stage in the darkness of the womb, will determine the structure and the organisation of the brain and that in turn will decide the very nature of the mind. (1989, p. 21)
Other books in this vein included Baron‐Cohen's The Essential Difference: Men, Women and the Extreme Male Brain (2003) and The Female Brain by Brizendine (2007). Baron‐Cohen's main focus is on the idea that evolution has shaped male and female brains to think differently, so that men are sytematizers and women empathizers. Brizendine claims that “scientists have documented an astonishing array of structural, chemical, genetic, hormonal and functional brain differences between men and women” (2007, p. 27). It is this confident assertion of the scientific basis of the idea of sexed brains that has elicited criticism from feminist scientists (Fine 2010; Jordan‐Young 2010).
Currently some of the most powerful criticism comes from feminist scholars linked to the group, the Neurogenderings Network (www.neurogenderings.wordpress.org). Like Fausto‐Sterling, the members of this group are biologists and neuroscientists so they are speaking from within the fold. Their aim is to counter examples of “neurosexism” (Fine 2010) by examining the scientific claims that are being made by those promoting the idea of the sexed brain. Neurosexism can be defined as the viewpoint that there are hardwired differences in the brains of men and women that account for the gender status quo, to paraphrase Fine (2010 p. xxv).
The scholars in this group want to replace neurosexism with “neurofeminism.” As it sets out on the website:
The NeuroGenderings Network is a transdisciplinary network of “neurofeminist” scholars who aim to critically examine neuroscientific knowledge production and to develop differentiated approaches for a more gender adequate neuroscientific research. Feminist neuroscientists generally seek to elaborate the relation between gender and the brain beyond biological determinism but still engaging with the materiality of the brain.
Notably these scientists are not against brain research into sex and gender. Instead, they are asking for a better quality of research. For example, they point out that images of the brain can only reflect current brain activity and not what causes it. When a close analysis of claims about brain sex is conducted it is striking how often they are made on the basis of animal studies, studies of humans using very small samples and so called “snap‐shot studies.” Fine et al. suggest that,
Focusing only on similarities or differences is misleading. We need
