Gender And Sexuality PDF

CHAP TER 2 2 Gender and Sexuality Gender is a system of classification based on sex 19 Gender development may form part of social learning in Gender stereotypes and gender identities 20 humans 28 A gender stereotype is the set of beliefs a...

CHAP TER 2 2 Gender and Sexuality Gender is a system of classification based on sex 19 Gender development may form part of social learning in Gender stereotypes and gender identities 20 humans 28 A gender stereotype is the set of beliefs about what it Patterns of interaction between babies and those around means to be a man or a woman in a particular society 20 them emphasize gender differences 28 Gender stereotyping provides a social shorthand for Gendered behaviour by babies may affect the way that classifying people by sex 21 they are treated 29 Gender identity describes the personal concept of ‘me as a Summary 30 man or a woman’ 22 Gender and reproduction 30 Gender differences may not be as great as they first appear Sexuality involves the erotic 31 to be 22 Sexuality can be classified by the stimulus of erotic The origins of gender 23 arousal 31 Hormones, the brain and behavioural dimorphism 24 Genetics, brain anatomy, androgens and social learning In animals hormones condition sex differences in have all been implicated in the formation of sexualities 32 behaviour and brain structure 24 The relationship between sexuality and gender 33 Non-human primates show sex differences in behaviour Summary 34 which appear to be influenced by hormonal exposure early Further reading 34 in life 24 Key learning points 35 In humans there may be both sex and gender differences in brain structure and the expression of gender attributes, but the underlying causes are uncertain 26 In Chapter 1, sex was defined in biological terms as the developmental relationships between them. There is an creation of a genetically unique individual as a result of assumption, broadly universal across cultures and history, the equal contribution of chromosomes from two parents: that the identification of one of these features as male or hence, two types of gamete (oocytes and spermatozoa) are female could reasonably be expected to predict that all the produced from two types of gonad (ovary and testis) in two other features would also be concordantly male or female. types of individual (female and male). What then is gender, Thus, the presence or absence of a penis at birth is taken how does it relate to sex, and where does sexuality fit in to generally as diagnostic of males or females, respectively. Of all of this? This chapter examines these questions. At the course, as described in Chapter 1, discordances can outset, it must be emphasized that there exists considerable and do exist, and we now understand more of the nature variation in the ways that these terms are used. The discus- and origin of many of them. Estimates of the incidence of sion that follows attempts to clarify the issues, explain ambiguous external genitalia are understandably problem- common usage and provide a consistent framework atic, but figures of 0.1–0.2% of babies with major ambiguity through which to consider gender and sexuality. and 1–2% with less severe ambiguity have been suggested (Box 2.1). Although small in percentage terms, this amounts to a large number of intersex individuals. The traditional Gender is a system of classification approach to genital ambiguity in Americo-European cul- based on sex tures has been to intervene as early in childhood as The features by which the two sexes were described and possible to remove or reduce ambiguity and assign a clear differentiated in Chapter 1 included their chromosomes, anatomical and thus social sex to the baby. An intersex state genes, gonads, gametes, hormones and anatomical struc- was not considered acceptable. However, other cultures tures (upper part of Table 2.1), and we explored the have taken a different approach, and accepted intersex 19  20 C HA P T E R 2 individuals for who they are, often according them a special here as a system of classification based on sex. In order to social status as a distinctive ‘third sex’, for example, the hijra distinguish sex from gender, we reserve the terms male and in India or the berdache among some North American indig- female to describe sexual features and the words masculine enous peoples. A move towards a more flexible approach to and feminine to describe gender attributes. The nature of the the clinical management of genital ambiguity has recently relationship between sex features and gender attributes occurred in Americo-European society, in part through forms the substance of this chapter. First, we will examine pressure from people who were assigned a ‘sex’ medically, in a little more detail some of the gender differences sum- and in their view inappropriately, as babies (see later). marized in Table 2.1. Then we will explore the basis of The bipolar biological classification of individuals as gender differences in behaviour since, collectively, these either men or women is paralleled by a bipolar allocation will influence social interactions and thereby the socially of many other traits, some of which are summarized in the based gender attributes. Lastly we will examine the repro- lower part of Table 2.1 as gender attributes. Unlike the fea- ductive and sexual attributes of gender and explore their tures characterizing sex, these attributes are based more on interrelationship with sexuality. attitudes, expectations, behaviour and roles; some of them may appear contentious or less absolute; many are complex; Gender stereotypes and gender identities and many vary in detail or substance with different cul- Two quite complex concepts need to be grasped for a sound tures or, within a culture, over historical time. In the table, understanding of gender. these attributes have been grouped under the broad heading of gender because they are associated with sex, but not A gender stereotype is the set of beliefs about what it obviously, invariably or simply so. Moreover, any causal means to be a man or a woman in a particular society relationships between those features listed under sex and those attributes listed under gender are not always imme- The gender attributes listed in Table 2.1 constitute the ele- diately obvious. It is for this reason that gender is defined ments of gender stereotypes. Gender stereotypes provide a Table 2.1 Sex and gender: oppositional descriptions. Sexual features Male Female Chromosome Y present Y absent Gene SRY active in Sertoli cell SRY inactive Gonad Testis Ovary Gamete Spermatozoon Oocyte Hormone Androgens, MIH No androgens or MIH External phenotype Penis, scrotum Clitoris, labia Internal phenotype Vas deferens, prostate, etc. Oviduct, uterus, vagina Gender attributes Masculine Feminine Inter-/intra-gender Pre- and proscribed contact and relational Distinctive patterns interaction patterns patterns Social role Public, extrovert, in the workplace, powerful, Private, domestic, powerless, quiet, care provider independent, forceful, outspoken Reproductive role Disposable and transitory Essential and enduring Sexual role Active, insertive, dominant Passive, receptive, submissive Work role Rule setting and enforcing, leadership, Constructive, agricultural, food preparation, military, ritualistic and priesthood, artistic domestic, creative, nurturant Appearance Characteristic and uniform hairstyle, body Characteristic and varying hairstyle, body decoration, clothes, ornamentation decoration, clothes, ornamentation Temperament and emotion Competitive, combative, aggressive, ambitious, Cooperative, consensual, expressive, empathic, not expressive of vulnerable emotions affectionate, emotionally free Intellect and skills Better mathematical and spatial skills, Better linguistic skills, people oriented systematizing Language used Words reserved for use by men Words reserved for use by women  G E N D E R A ND SEXU AL ITY 21 in British society very gender astereotypic: there were B O X 2. 1 How frequently is concordance for social rules about what constituted appropriately gendered chromosomal, gonadal and genital sex absent? body decoration and clothing, many of which still linger in Cause Estimated frequency/ today’s attitudes and values, albeit much attenuated. 1000 live births Although it may appear difficult in a society in flux to Non-XX females or non-XY males 1.93 define the current gender stereotypes in terms acceptable Complete or partial androgen 0.08 to all, nonetheless there tends to be a normative social view insensitivity about those elements constituting masculine and feminine Congenital adrenal hyperplasia 15.08 behaviour. The cohesiveness of that view can be particu- True hermaphrodites 0.01 larly strong for the members of each generation: a person’s Vaginal agenesis 0.17 peers. In framing a gender stereotype, no claim is being In the UK, the birth certificate has to record the baby’s made that this stereotype is true for all or indeed for any sex as male or female; intersex is not a legal option (Births female or male. It is rather a shared cultural belief about and Deaths Registration Act of 1953). Interestingly, the what men and women are like. This social consensus about Adoption and Children Act of 2002 does allow parents to what it means to be a man or a woman is important for be registered by the ‘sex neutral’ term ‘parent’. This individuals’ perceptions of themselves and of those around neutrality accommodates adoption by same-sex couples them. It provides a yardstick against which to measure (both male or both female), thereby avoiding two mothers their own masculinity or femininity and that of those whom or two fathers. It will be interesting to see whether this they meet. precedent leads to pressure for sex-neutral birth and/or This measuring process is important because those who death registrations, or even for the recording of ‘intersex’. appear to stray too far from the stereotype are generally Such pressure may come from the increasingly prevalent regarded negatively or as a focus for rebellion. In societies clinical practice of conservative surgical and endocrino- logical intervention in cases of sex ambiguity until the in which gender plays a strong social role, it is less accepta- child grows and expresses a gender identity as masculine, ble for men to appear feminine than for women to appear feminine or intermediate. masculine, although there are boundaries in both directions. This asymmetry may result from the fact that men tend to Data adapted from Blackless M et al. (2000) How sexually be more powerful than women, and so their attributes are dimorphic are we? Review and synthesis. American Journal of more valued socially. So in societies in which gender stere- Human Biology 12, 151–166. otypes are being eroded, there tends to be more acceptance of the perceived masculinization of women’s stereotypes and more resistance to the feminization of men’s stereo- description which is broadly recognizable as defining what types. However, as economies shift increasingly towards a it means to be masculine or feminine in a society. The precise service function, in which traditionally feminine attributes attributes appropriate to each gender will vary from one are more valued, the employment opportunities for tradi- society to another, or in the same society over time. tionally masculine men are reduced and these men become However, social, historical and anthropological studies marginalized as their masculine attributes are less valued. reveal a remarkable consistency in the extent to which each A key message from this brief discussion is the strong cul- of those attributes listed recurs with greater or lesser tural contingency of gender attributes. emphasis in the gender stereotypes of a range of different societies. For example, the exclusion of women from public Gender stereotyping provides a social shorthand for life or from particular social or work roles is more evident classifying people by sex in strict Islamic societies or traditional Judaeo-Christian societies than in modern secular societies. However, in the We are presented with a bewildering array of social infor- latter societies such gender stereotyping still persists in that mation. Part of the process of our development as children certain roles remain associated strongly with men (e.g. con- is to learn how to interpret the world around us. Sex dif- sultant surgeons, priests) or women (e.g. nurses, midwives) ferences are an important part of that world. By learning a even if many of these associations are much weaker than gender stereotype, or indeed any other stereotype (ethnic- they once were. The behaviour expected of men and women ity, race, class, age, employment), one is provided with a also differs. Rowdy, aggressive behaviour from men is social shorthand or sketch that enables some rapid prelimi- resignedly expected and often excused (‘boys will be boys’), nary assessments to be made of each individual encoun- whereas the same behaviour from women is considered tered. Recognizing someone as male or female allows us to ‘unladylike’. On a more trivial level, the wearing of ear- associate the various attributes of gender stereotypes and rings by men or of trousers by women was until recently thereby conditions our immediate behaviour patterns in  22 C HA P T E R 2 ways that are socially appropriate for our and their gender. Of course, this process will tend to reinforce the gender BO X 2. 2 The law and trans men and women stereotype of the society. It does not, however, preclude Recent legislative changes across Europe permit recogni- later reactions to the individual as an individual. If you tion of trans men and women in their ‘new’ identities. In doubt the importance of social sketching of this sort, con- the UK, the relevant law is the Gender Recognition Act sider your reaction on being introduced to someone whose 2004, which provides for a ‘gender recognition certificate’ sex and gender are not immediately obvious. How com- meaning that their legal sex does not match that on their fortable are you, and how does it affect your behaviour? Or birth certificate. In order to qualify for a certificate, ‘expert evidence’ must be produced to establish the person’s consider how you react when, in a different culture, you gender identity, effectively a gatekeeper role for clinicians. find that the accepted gender stereotypes conflict with Then, only after 2 years living in one’s ‘acquired gender’ those of your own culture: for example, men holding hands (the terminology the Act uses) can the person get a or kissing in public or women being excluded from public certificate. Third, the person’s birth certificate remains life? Humans are social beings and the rules by which unamended. Although legally this is not a problem, some societies function are therefore very important. trans people argue that this is a failure to accept that the surgery or treatment is to match them to their true sex and that the sex on the birth certificate was an error. Gender identity describes the personal concept of ‘me as a man or a woman’ We have a social view that there are two genders defined understanding of the basis of trans people may also help broadly by the gender stereotypes of our society. Each of us to refine more clearly the boundary between sex and us is part of that society. It therefore follows that each of gender. us has a view of ourselves as being masculine or feminine and of conforming to a greater or lesser degree to the stere- Gender differences may not be as great as they first otype. The extent to which each individual feels confident appear to be of his or her position within this bipolar gender spectrum is a measure of the strength and security of their gender Intuitively, when looking at the gender attributes in Table identity. Most individuals have gender identities that are 2.1, it is possible simultaneously to recognize the gender fully congruent with their sex. Thus, most women and stereotypes as familiar while rejecting them as an oversim- men who are physically female and male, respectively, plification. For example, whereas men in general might not have strong gender identities. Some individuals may feel less readily express vulnerable emotions through crying and certain about their gender identities, although they none- admissions of helplessness, many individual men do theless identify congruently with their physical sex: they express such emotions and show such behaviour. Individ- may be said to have weak gender identities. A few individuals ual women can be just as competitive and aggressive as may feel that their gender identities are totally at variance men, although overall these attributes are associated much with their otherwise congruent genetic, gonadal, hormonal less with women than with men. Many studies have and genital sex. Such people are described as being trans- attempted to make objective and quantitative measure- sexual or transgendered. Transgendering may occur in either ments of gender differences, through the use of behav- direction, the male-to-female transgendered consider them- ioural and cognitive function tests and the use of selves to be females with a female gender identity and questionnaires to address attitudes. For most attributes, the brain but with otherwise male bodies, whereas the female- degrees of variation within populations of men and of to-male transgendered feel themselves to be men in an other- women are so great that the overlap between men and women wise woman’s body. Traditionally, more male-to-female is too large to produce significant differences between the transgendered individuals have been identified than sexes (see Box 2.3). Moreover, rarely if ever do any differ- female-to-male, although this may represent differential ences observed have predictive validity: it is not possible reporting more than real prevalence. The transgendered from the measurement of a gender attribute in an individ- may adopt the gender roles of the physically different sex, ual to predict whether that individual is a man or a and some may undergo surgical and hormonal treatments woman. so as to bring their bodies and their bodily functions (their There is thus a paradox. Society has a clear and polarized sex) as closely congruent to their gender identity as is pos- concept of what it means to be masculine and feminine sible (females becoming trans men and males becoming within society. Moreover, most individuals profess a very trans women) (Box 2.2). Transgendered men and women clear concept of themselves as masculine or feminine and provide us with perhaps the strongest justification for an understanding of what that means for their place in making the distinction between sex and gender. A better society. Yet both objectively and subjectively it is not  G E N D E R A ND SEXU AL ITY 23 B O X 2. 3 Summary of findings from a meta-analysis of is to focus on those statistically significant average studies on sex differences in humans differences that are observed and to seek to understand their origins—the ‘women are from Venus, men are 124 traits were analysed in a range of published studies to from Mars’ approach. This reaction may also be used to see whether there were significant differences between justify the perceived different needs/treatments of men/ populations of men and women. boys and women/girls in education, health, employment, For 78% of these traits, there was effectively no etc. difference. The alternative approach, while accepting that some For 15% of them, there was a moderate population average differences do exist between the sexes, is to focus on difference. Traits observed more frequently in the male people first and foremost, given the overlap between sexes population included spatial perception, mental rotation, and complex biological and social origins of sex differences. physical and verbal aggression, assertiveness, body This approach accepts the notion of a less gendered society esteem, sprinting, activity level, self-efficacy of than hitherto in which people of either sex are freer to computer use. Traits more frequently observed in flourish without constraint of stereotype. A recent debate women included spelling and language skills, and about biological sex differences among scientists illustrates smiling when aware of being observed. these distinctive reactions (see Further reading). These two For only 6% of traits were large differences observed. differing approaches take us into political and social theory, Observed more frequently for men were mechanical and we simply alert readers to read and interpret the reasoning, masturbation, permissive attitudes to casual evidence base as objectively as possible despite the strong sex, and for women agreeableness. academic and social reactions that discussion of sex Only 2% of traits showed very large sex differences, differences evokes. throw velocity/distance and grip strength being significantly more frequent in males. Further reading Baron-Cohen S (2003) The Essential Difference: Male and Female Brains Conclusions and qualifications and the Truth about Autism. Basic Books, New York (takes quite a It is important to note that for all traits there was overlap. strong position about innate biological differences between male Some are clearly related to the anabolic actions of and female brains, and relates the analysis to the higher incidence androgens on muscles, and others may be culturally of autism among males; acknowledges considerable overlap and conditioned—expectations from gender stereotypes sex-atypical patterns). perhaps influencing attribute acquisition. Barres BA (2006) Does gender matter? Nature 442, 133–136 (questions biological origins of sex differences in scientific success). Where statistically significant sex differences are found, Shibley Hyde J (2005) The gender similarities hypothesis. it is important to note that scores for some traits may vary American Psychologist 60, 581–592 (the meta-analysis that with factors such as age and experience, mood, motiva- emphasizes the similarities rather than the differences between tion, practice and ambient hormone levels, and that these the sexes). may differ for the two sexes. Lawrence PA (2006) Men, women and ghosts in science. PLoS Biol. 4, Overall, what impresses is how similar the two sexes e19, 13–15 (takes the approach that biological sex differences are are. Humans do not seem very dimorphic! inevitably a part of our makeup as humans and scientists and cannot be ignored). Gender differences nonetheless are often highlighted There are two types of reaction to the evidence that men and women show big overlaps in attributes. One reaction possible to sustain a strongly bipolar description of a gen- In order to take this discussion further, we will turn to a dered society. Men and women overlap greatly in the atti- consideration of how a gendered society might arise. tudes that they express, in their patterns of behaviour, in The origins of gender their skills and, increasingly, in the roles they adopt. There is more a continuum of attributes than a bipolar segrega- It will be clear from the foregoing discussion that gender tion. Some societies reflect this reality and are relatively is a concept applicable to humans. Does this therefore mean non-gendered, but most societies have a bipolar gendered that studies on the origin of sex differences in the behaviour organization despite the lack of evidence for its inevitabil- of animals are of no use to us in trying to understand ity. Why? Presumably such social organization is seen to gender differences in humans? We examine this question have advantages, for example for the production and first for non-primates, and then for non-human primates, raising of children, controlling patterns of inheritance, the before finally considering whether and how this evidence division of labour, or the ability to resist external threats. applies to humans.  24 C HA P T E R 2 Exposure to steroids over the critical period affects the Hormones, the brain and structure of the developing brain, generating many neuroana- behavioural dimorphism tomical sex differences, some of which seem to explain the sex differences in behaviour. Most attention has focused on In animals hormones condition sex differences in structural sex differences in a region of the brain called the behaviour and brain structure anterior hypothalamus and adjacent medial preoptic area (the Exposure of animals to sex hormones during a critical anatomy of these regions is discussed in more detail in period of early life is associated with sexually dimorphic Chapter 6). Both of these areas are known to be intimately behaviour displayed later in adulthood, for example, the involved with the control of sexual behaviour in adult distinctive urination patterns shown by the dog (cocked animals (see Chapter 8). Indeed, neonatal implantation of leg) and bitch (squatting). This critical period may be in late androgens directly into the anterior hypothalamus of fetal life (e.g. guinea-pig, sheep) or neonatally (e.g. rat, female rodents not only masculinizes the local brain struc- mouse, hamster). The most intensively studied behaviour ture but also results in increased reproductive male behav- patterns are those associated with copulation. Thus, during iour in adulthood (Fig. 2.2). sexual interaction with females, adult male rats show court- In animals, then, there is clear evidence that hormones ship behaviour (e.g. pursuing females and anogenitally investi- lead to neuroanatomical and behavioural changes, in much gating them), mounting, intromission and ejaculation (Fig. the same way that they also lead to the development of 2.1). Conversely, adult females display soliciting and recep- sexually dimorphic genitalia. However, it is important to tive postures, such as lordosis (Fig. 2.1). These behaviours are remember that it is quantitative sex differences in behaviour predominantly, but not exclusively, typical for each sex. Thus, that are observed, not absolute differences of a qualitative normal males will occasionally solicit and even accept nature. It is therefore oversimplistic to believe that particu- mounts by other males, while females in heat will often lar sexually dimorphic areas of the brain are reliably associ- mount one another. The differences in behaviour are not abso- ated with specific behavioural functions. Some behavioural lute but quantitative. flexibility persists. However, our broad understanding of Treatment of female rats with testosterone during the these animal studies enables us to fit sex differences in first 5 days of life increases their display of masculine pat- brain structure and in behaviour into the same conceptual terns of sexual behaviour in adulthood and reduces their framework of sex, as we did for the gonads, hormones and display of feminine patterns. Castration of male rats to genitalia in Chapter 1. There is then no need for a ‘gender remove the influence of androgens during this same critical category’ in these species. period has the reverse effects. Thus, ‘masculinization’ in the rat (and other non-primates) is accompanied by ‘defeminiza- Non-human primates show sex differences in behaviour tion’. How do androgens influence the development of which appear to be influenced by hormonal exposure these behavioural differences? early in life To what extent do androgens exert the same effects on the development of sexually dimorphic behaviour in non- human primates? Results from experiments on rhesus monkeys suggest some similarities. Young females, exposed to high levels of androgens during fetal life, display levels of sexually dimorphic behaviour in their patterns of child- hood play that are intermediate between normal males and females (Fig. 2.3). Moreover, although both male and female infant monkeys will mount other infants (Fig. 2.4a), only males progressively display mounts of a mature pattern (Fig. 2.4b). Androgenized females, however, do develop this mature mounting pattern. Moreover, as adults they attempt to mount other females at a higher frequency than Fig. 2.1 Sex-dependent behaviour patterns in male and female do non-androgenized females. Thus, neonatal androgeni- rats. Note the immobile lordosis posture shown by the receptive female, which enables the male to mount and achieve zation produces persistent ‘masculinization’ of behaviour. intromissions which will result in ejaculation. Receptivity and However, the androgenized female monkeys as adults lordosis are shown predominantly by females; mounting, show normal menstrual cycles and can become pregnant. intromission and ejaculation patterns of behaviour are shown They must therefore display patterns of adult feminine predominantly by males. sexual behaviour at least adequate for them to interact  G E N D E R A ND SEXU AL ITY 25 (a) ISDA SDApc mSDA (b) ISDA Fig. 2.2 Photomicrographs of coronal sections through the preoptic area of three 21-day-old gerbils (Meriones unguiculatus). Section (a) is taken from a male, (b) from a female and (c) from a female treated neonatally with mSDA androgens (testosterone propionate: 50 mg on the day of birth and 50 mg the next day). The sexually dimorphic area (SDA) can be divided into several regions: medial (mSDA); lateral (lSDA); and pars compacta (SDApc). The SDA differs between males and females in a number of aspects: prominence (not necessarily size); acetylcholinesterase histochemistry; steroid binding; and various other neurochemical characteristics, but (c) most obviously in the presence or absence of the SDApc. Thus, the SDApc is virtually never found in females (compare a with b). Note that in females treated neonatally with testosterone, ISDA there is a clear SDApc (compare c with b). These pictures provide clear evidence of the impact of hormones during a critical period of early life on the differentiation of this part of the brain. The medial preoptic area in general is closely SDApc involved with the regulation of sexual behaviour (see Chapter 8), and some progress has been made in relating specific aspects of sexual behaviour to subdivisions of the SDA. It is mSDA also important to note that such sex differences in the structure of the preoptic area are found in many species, from rats to humans, but the precise details of the dimorphism vary considerably. successfully with males, suggesting that they are not totally critical period exists in primates, it occurs during fetal life, or permanently ‘defeminized’. and may be prolonged. Attempts to androgenize primate These results suggest a less complete or persistent effect fetuses in utero often lead to abortion if doses of adminis- of androgens on the development of sexually dimorphic tered androgens are too high. The genitalia also tend to be behaviour in primates than in non-primates. Why might masculinized, which might affect the subsequent social this be? One explanation lies in the timing of the critical interactions and learning of the infant. Thus, a specific androgen-sensitive effect on brain structure. In rats, this selective effect of androgen on the brain may not yet have occurs neonatally, after genital phenotype is established, so been achieved. Alternatively, it is possible that in non- making it easily accessible to selective manipulation. If a human primates, the rather rigid hormonal determination  26 C HA P T E R 2 (a) Under 1 year old 1 year old 2 years old 40 Frequency 20 (b) 0 Successive observation periods Fig. 2.3 Frequency of ‘rough-and-tumble play’ during the first, second and third years of life of a rhesus monkey male (red circles), female (blue squares) and female that had been treated with androgens prenatally (green circles). Note that males display this behaviour at a higher frequency than females and that androgenized females are intermediate. of sexually dimorphic behaviour seen in non-primates Fig. 2.4 Sexually dimorphic patterns of mounting behaviour in simply does not occur. Androgens may predispose to mas- young rhesus monkeys. (a) Early in life, both males and females show immature mounts by standing on the cage floor. culine patterns of behaviour, but other factors may also (b) During development, males show progressively more mature influence the degree to which they are expressed. mounts in which they clasp the female’s calves so that she What about sex differences in brain structure in non- supports his weight entirely. Androgenized females display human primates? As for non-primates, a few such differ- more of the latter type of mature mounts than do untreated ences exist, including some in the hypothalamic region females. particularly concerned with reproductive and sexual behaviours. However, although it seems probable that most of these neuroanatomical differences result from endocrine exposure in early life, this has not been demon- artefacts. Although studies are limited and often conflict- strated formally. Neither has a strict association between ing, a few consistent sex differences in the structural organ- sexually dimorphic brain structures and behaviour been ization of the brain have been reported, for example in a shown. small region of the anterior hypothalamus called the 3rd interstitial nucleus (INAH3). However, the significance of these sex differences for gender identity and attributes is In humans there may be both sex and gender less clear. A claim has been made that the size and organi- differences in brain structure and the expression zation of the central bed nucleus of the stria terminalis (cBST) of gender attributes, but the underlying causes is associated specifically with gender identity as opposed to are uncertain sex. Thus, it is reported as being smaller in women than in Not surprisingly, the difficulty in studying non-human pri- men, and also smaller in trans women (male-to-female mates is exacerbated further when the human is consid- transgendered; Fig. 2.5). However, the number of individ- ered. The requirement to use post-mortem brains for ual brains studied is small, as are the measured gender neuroanatomical analysis restricts both the amount and differences, and there is overlap between genders such that quality of the material, and observations are complicated nuclear size is not predictive for gender. It is also not clear by variations in age, pathology, experience and structural when these size differences first appear or what causes  G E N D E R A ND SEXU AL ITY 27 them. Until we know more about the time at which brain has been fruitfully investigated in genetic females with differences emerge and we are able to study more brains adrenogenital syndrome (AGS; see Chapter 1)—nature’s from a larger range of individuals with gender or endo- counterpart to experimental animals treated exogenously crine anomalies, it will be difficult to draw firm with androgens during the critical period of neural differ- conclusions. entiation. However, it is important to note that we are not More recently, neuroanatomical imaging techniques dealing with ‘pure’ androgen effects in these girls/women, have been used to search for male/female differences in the as under- or (therapeutic) overexposure to corticosteroids functional organization of the living brain. A number of is known to affect brain structure and behaviour directly. these studies has now shown that there are population sex Studies of girls with AGS has revealed increased levels of differences in brain lateralization of some functions, females energy expenditure and athletic interests more characteris- showing more left-lateralized language and emotion tic of boys, and a decreased incidence of ‘rehearsals’ of processing, whereas males tend to show right-lateralized maternal behaviour and doll-play activities, together with visuospatial activity. There is also evidence for sexual diminished interest in dresses, jewellery and hairstyles. dimorphism in the amygdala, a region of the brain involved This spectrum of behaviour, termed tomboyism, is well rec- in emotional processing. Overall, more study is needed for ognized and accepted in Western culture, and provides few secure identification of sex and/or gender based brain if any problems for children so affected. Tomboyism might organizational differences. Certainly, claims as to the hor- be thought to be a consequence of the effects of androgens monal cause(s) of any differences must be viewed cau- on the fetal brain, rather like the changes in rough-and- tiously. For example, genetic differences (one versus two tumble play in infant monkeys exposed prenatally to X chromosomes) have been claimed as responsible for androgens. However, as a group, AGS girls had stronger amygdala dimorphism. feminine gender identities than a group of non-AGS What about the relationship between hormones and gen- tomboys, and only slightly weaker gender identities than dered behaviour in humans? This question has been studied control girls. Moreover, among AGS girls there was no in both adults and children using various of the gendered clear relationship between weak feminine gender identity attributes summarized in Table 2.1. It is important to re- and the degree of genital virilization. Further study of AGS emphasize that in humans the two sexes differ quantita- females as adults has revealed only slender evidence of tively in gender attributes, with much overlap. The enduring behavioural consequences. Thus, they show only influence of prenatal hormones on subsequent behaviour slight evidence of a higher incidence of dissatisfaction with their female gender identity and of lesbianism than did controls, but again not related to the degree of presumptive androgenization. A small group of AGS women do identify as trans men, but again not necessarily the most androgen- 4 ized. Thus, overall the studies on AGS girls/women provide little support for either androgens or masculinized genitalia being an exclusive or necessary determinant of 3 defeminization in humans. However, it is important to note that the AGS girls and women studied will, by definition, Size of nucleus span the low to moderate part of the androgenization scale, 2 where genital virilization is incomplete. How to summarize? It seems clear that there are some sex differences and even perhaps a gender difference in brain structure in humans, but these differences are small. 1 It is unclear when they arise and what causes them. There is no direct evidence relating them causally to particular behavioural differences between genders. Evidence from 0 animals suggests that hormones can influence brain organi- Male Female Transgendered zation and thereby behaviour, but even in animals there is a not a rigid and absolute causal relationship between the Fig. 2.5 The scatter of sizes of the central bed nucleus of the stria two. In humans, where there is even greater flexibility and terminalis (cBST) in human adult males, females and trans males overlap of sex-related behaviour patterns and of gendered (male-to-female transgendered). Error bars ±SEM. Note the sex attributes, a role for hormones prenatally or neonatally is difference and that the trans male nuclear volume is closer to the plausible but more research is needed to find out the full female pattern. Data redrawn from Zhou et al. (1995). extent and nature of any influence (see also p. 119).  28 C HA P T E R 2 and discourage. Rewards and approval are offered when Gender development may form part of children conform to parental gender stereotypes. These social learning in humans parental gendering activities are particularly marked for In the discussion above, we referred again to the signifi- the first 2–3 years of a child’s life. It is precisely over this cance of the assignment of sex to a baby as a boy or a girl period that a child develops its own sense of gender iden- depending on the presence or absence of a penis. It was tity. By 2 years children label themselves consistently as pointed out that this assignment might then affect both male or female, and soon thereafter reliably associate how the individual saw him- or herself and how the parents certain sorts of behaviour and activities with males and and peers viewed and treated the developing child. We females. They appear to have both a gender identity and now explore this area further in our analysis of gender a gender stereotype. They also by 5 years of age seem to development. realize that gender is fixed and cannot be changed across time or situation: they have a sense of gender constancy. Indeed, if 3–6-year-old children are shown a video of Patterns of interaction between babies and those another child, their descriptions of its behaviour are very around them emphasize gender differences different if told that it is a boy than if told it is a girl. They Starting from birth, mothers attribute different character- actually seem to be even more rigidly gender stereotyping istics to male infants than to female infants. Thus, when than their parents when performing the same task! Since individual adults are handed the same baby, having been children spend a lot of time with one another, they are told variously that it is a girl or a boy, their play, handling likely to reinforce gender stereotypes in each other: peer of and communication with it differ according to their perception pressure in action. of its sex. This sort of study shows that babies of different Children are, of course, cognitive beings. They do not sexes are likely to be treated differently simply because simply absorb subconsciously impressions of the world they are of different sexes. A second example makes an around them, although that does occur. They see and hear additional point. When adults are shown the same video what goes on around them in the household, in the media, sequence of a child playing, and some are told that it is a at school. They see men and women and what they do boy and others a girl, their interpretations of its behaviours and don’t do. Models of male and female behaviour are depend on the sex that they believe it to be. For example, when provided all round them. So there may also be a copying the child was startled and believed to be a boy, it was element in the development and elaboration of their perceived more often as being angry, whereas the same growing gender identity and the ways in which they startled behaviour, when believed to be that of a girl, was express it. However, copying a model implies identification perceived as fearful distress. This sort of study tells us that with that model in the first place and so it is likely expectations about how a male or female baby should that copying is a secondary process that may relate behave can lead adults to interpret the same behaviour more to the expression of a gender identity than its initial very differently. It raises the possibility that some behav- establishment. iours may be reinforced or responded to in different Thus, a lot of evidence supports the view that gender gender-specific ways as a result of the expectations of stereotypes are applied to babies and children very early others. Several studies have shown very clearly that the in life, and that children also use them and apply them to expectations that adults have of a boy differ from those their world from an early age. The child’s environment is expected of a girl; and men tend to be much more prone thus immersed in gender stereotyping. Does this mean that to gender stereotyping in this regard than women. Thus, the way in which babies are treated and gender stereotyped girls are expected to be softer and more vulnerable and are causes their own gender to develop? It is entirely plausible played with more gently. They are also expected to be to suggest that at least some gendered patterns of behav- more vocal and socially interactive, and parents spend iour that develop in boys and girls may be induced differ- more time in these sorts of behaviours with girls. Boys in entially by the way in which they are treated by others and contrast are encouraged to do things, are less directly com- as a result of the expectations of others. In effect, the gender municated with and are disciplined or roughly handled stereotype of a society may be ‘taught’ to its children by more often. the way they are treated. If this were so, it might be sug- These sorts of observations emphasize how important gested that ambiguity on the part of parents about the sex and subtle gender stereotypes are and how they are applied of their child could affect the development of gender iden- to children from the moment of birth. Indeed, parents tity. Cases of transgendering might be associated with a seem quite anxious to encourage differences between boys sexually ambiguous childhood: for example, parents treat- and girls by the types of toys they offer them, the clothes ing their son more as a girl, clothing him in dresses and not they provide for them, and the activities they encourage reinforcing ‘boyish’ activities in play and sport. The evi-  G E N D E R A ND SEXU AL ITY 29 dence on this suggestion is far from clear. Just because a suggestion is plausible, it does not mean that it is true. BO X 2. 4 The Money twins and their impact on What is the evidence? paediatric practice John Money was an eminent sexologist, and the John/ Joan twin case was highly influential on paediatric policy Gendered behaviour by babies may affect the way in cases of sexual ambiguity. The general principle that that they are treated developed from it was that clinicians alone should decide In an earlier section, the evidence that exposure to andro- on a course of sex assignment and then reinforce that gens during fetal or neonatal life might influence gendered decision in all that was said to parents and the child concerned. Thus, early surgical and endocrine interven- behaviour was reviewed. The evidence was consistent with tions were undertaken, and neither parents nor develop- there being a possible influence on childhood play patterns. ing child were told about the ambiguity of sex (‘just There are indeed claims of intrinsic behavioural differences treating a developmental incompleteness’). This well- between newborn male and female babies, although these intentioned clinical paternalism was intended to foster are not yet strong enough to convince. However, it is at clear parental commitment to a clinically agreed sex of least plausible to suggest that just as babies may respond rearing, so as to facilitate the child’s entrance into a highly differently to adults who show gender-specific behaviour gendered society. However, when the outcome of the towards them, so sex differences in baby behaviour might John/Joan case became known, with Joan rejecting her induce different responses in adults. Clearly, the experi- feminine identity, this policy was undermined and was ments described above, in which adults were (correctly or abandoned by the American Academy of Pediatrics in the incorrectly) ‘told’ the sex of a child and responded in ways late 1990s. Both in the USA and elsewhere attempts are now under way to develop and review more sensitive typical for the believed gender, cannot be explained in this policies for the management of sexual ambiguity. These way. However, in these experiments when a male baby was take account of recent outcome studies, such as Reiner’s handled by adults, half of whom thought it was male and below, of changing social attitudes as well as of the the other half of whom thought it was female, and they parents’ concerns. These policies encourage minimal early were then asked about their experiences, there were differ- interventions, as far as possible restricted to those ences. Thus where reality and belief were congruent the necessary for medical reasons. adults had felt more ‘comfortable’ than when there was conflict. This may mean that they were picking up on Further reading inconsistencies in the baby’s behaviour that conflicted with Chau P-L, Herring J (2004) Men, women, people: the definition of sex. In: Sexuality Repositioned: Diversity and the Law (ed. B. expectations. What this may be telling us is that adults are Brooks-Gordon et al.), pp. 187–214. Hart Publishing, Oxford. sensitive to the baby’s behaviour as being boy-like or girl- Money J, Ehrhardt A (1973) Man & Woman/Boy & Girl: The like. It does not, of course, tell us whether these sensed Differentiation and Dimorphism of Gender Identity from Conception differences in behaviour were due to hormonal influences to Maturity. Johns Hopkins University Press, Baltimore, MD. on the baby or to previous social learning by it. Here is the Reiner WG (2005) Gender identity and sex-of-rearing in children with disorders of sexual differentiation. Journal of Pediatric core of our dilemma. From the moment of birth, boys and Endocrinology & Metabolism 18, 549–553. girls are likely to be treated differently, so how can we separate cleanly the effects of hormones from those of learning? One way to achieve this might be to look at babies who diatric policy on genital ambiguity until the late 1990s (see were born boys but ‘became’ girls postnatally (or rarely Box 2.4). vice versa). A single highly influential case was provided Recently, more systematic prospective studies on the in the 1960s by monozygotic male twins—the so-called development of gender identity in a range of patients with Money twins, named after the clinician who described the different combinations of genetic, gonadal, genital and case. One twin (John) was genitally damaged at circumci- rearing sex have begun to appear. These are based on thor- sion. This boy was reassigned as a girl (Joan), given genital ough descriptions of each sex-variable in relation to the plastic surgery, provided with hormone therapy and measured outcome of gender identity. At best, conclusions brought up as a girl. Joan was described as having a female are highly provisional, but suggest that many XY individu- gender identity and was taken by John Money as decisive als exposed to normal prenatal androgens but reared as evidence that sex of rearing ‘trumped’ genetic, endocrine females are likely to declare male sexual identities later in and gonadal sex in the establishment of gender identity. life. XX individuals exposed to high prenatal androgens However, it was later found that in adulthood, Joan rejected and reared as males are more likely to develop male identi- her female identity, reverted to John, married and had an ties. Such evidence is important if assignment of sex at adopted child. Amazingly, this one case determined pae- birth or soon thereafter is to be attempted. Of course, the  30 C HA P T E R 2 alternative, as described earlier, is to accept the intersex we saw in Chapter 1, is fundamentally about reproduction state as a valid interim and/or long-term option—a situa- and genetics. The process of reproduction involves the tion that would require both social and legal sanction for bringing together of a male and a female (courtship) so that it to be acceptable to many parents. their haploid gametes can unite at fertilization. In mammals, These studies indicate that the establishment of gender one of each type of gamete is obligatory for the successful identity is clearly complex and roles for both the gender of production of a new individual. As we will discuss further rearing and fetal androgens are likely, perhaps interacting in Chapter 9, in mammals fertilization is internal: it involves in ways we do not yet understand. In this context, the male the process of coition in which the spermatozoa are depos- transgendered are of particular interest. We need to under- ited in the vagina. Courtship and coition can involve elabo- stand whether their exposure to androgens was normal rate rituals and behaviours in which males and females and whether they were reared unambiguously as boys express sex- or gender-dependent patterns of behaviour. according to their genital sex. They develop a feminine Even a brief look at the gender attributes listed in Table 2.1 gender identity, but why? Understanding how the trans- reveals that many can be related plausibly to the different gendered develop may throw interesting and important reproductive roles of males and females. The generally light on the relative roles of hormones and environment in nurturant, emotional, consensual, creative and private gender development. attributes of females and the more aggressive, competitive, powerful attributes of males seem well suited to the explic- Summary itly reproductive gender roles. Thus, males are essentially disposable. Their only necessary role in reproduction is Four potential elements that might contribute towards the briefly discharged, whereas females have an extended essen- establishment of gender have been considered: sex chromo- tial role. Because of this, females are a precious resource who, some constitution, hormones, social learning and brain in times of danger, must be given protection if the social structure. The brain is central since the expression of atti- group is to survive. A single male could, in principle, tudes and behaviour, which form the basis of social interac- provide all the sperm needed for many females. Moreover, tions, is the result of neural processes. Both the organization all those unnecessary males will be a drain on resources if and function of the brain can be influenced by genes, hor- food is limited: males are costly biologically. They are mones and learning. Hormones affect brain structure and therefore disposable in war or in risky competition with one behaviour in non-primates and modulate behaviour sex- another. It is thus tempting to explain gender differences in dependently in primates, although their impact is less human societies entirely in terms of their value to the rigid. The patterns of usage of neuronal circuits that come reproductive process. It is also tempting to conclude that from interactions with the environment, including social the broad similarities between the reproductive roles of learning, can affect brain organization and function, so that animals and humans must mean that gender differences in learning and rehearsal are associated with changes to the humans, like sex differences in animals, are the product of ‘hard wiring’ of the brain. When we consider the develop- an evolutionary process which is, at its heart, genetically ment of gender, a clear separation of endocrine and social programmed and so ultimately genetically determined. factors has not been achieved. It might be suggested that These temptations should be resisted. such a rigid separation is also impossible, since each may Undoubtedly the genetic inheritance of humankind interact with and reinforce the other. Small gender differ- exerts powerful effects on us and our behaviour. However, ences in the behaviour of newborn babies may be induced what distinguishes humans from most other animals is by androgens. These subtle differences may be detected by the powerful additional legacy left to us by our culture. parents and peers who also have clear expectations and Humans are distinguished by our capacity to use informa- beliefs derived from gender stereotypes that condition tion around us, to learn as we grow, to conceptualize and their behaviour towards the baby’s actions and anatomy. to establish and transmit cultures, including complex lan- These interactions tend to amplify small differences into guage, in ways not open to most animals. This mental larger ones. Soon the baby/child engages in the process flexibility may operate within limits imposed by our actively. The process is a dynamic one, susceptible and genetic inheritance, but it also operates on opportunities responsive to cultural difference and change, based on the presented by that same inheritance. Even a superficial undoubted cognitive flexibility of humans, and well suited view of the widely different cultural roles that men and to the development of a social mammal. women have in different societies, how they are treated, are valued and behave, shows the power of cultural inher- Gender and reproduction itance. This is not surprising, given what we saw of how Gender has been defined and discussed as a system of clas- children learn about gender stereotypes from the society sifying individuals based on their sex. Sex in mammals, as around them.  G E N D E R A ND SEXU AL ITY 31 So reproduction and sex are tightly, inevitably and invar- feelings. This state of sexual excitement in humans is iably linked through our biological and genetic inheritance, described as the erotic. In this book, we reserve the use of whereas reproduction and gender are linked more loosely the term sexuality for this erotic experience and its expres- and elastically through our cultural inheritance. This point sion in human lives. This definition is not uniformly agreed is made more clearly when we examine the varied func- and would be considered by some to be controversial and tions associated with courtship and coition in humans. too narrow. Sometimes, sexuality is used to describe all that Reproduction is obviously one such function. However, it means to be a man or a woman, a sort of all-pervasive erotic pleasure quite distinct and separable from reproduc- state that is difficult to distinguish clearly from gender tion is another: humans can and do mate regardless of their itself. We find this definition too diffuse to be useful. Of fertility. The process of mating is an object in itself. Court- course, the erotic and its associations can be very pervasive ship and coition can also serve a wider emotional purpose, and, as we will see, not limited simply to the events sur- involving feelings such as dependence, power, self-worth, rounding courtship and coition. However, at heart, our and security. Courtship and coition also have social and sexuality is about inner erotic excitement and fantasy and economic functions: when formalized in kinships they its outward expression in sexual erotic behaviour. A sexual establish patterns of inheritance and power in a society. We individual is one who is erotically functional mentally and/ should also remember that coition has a consequence not or behaviourally, an asexual individual lacks erotic experi- always welcomed by humans, but essential for some micro- ence and fantasy. organisms, of transmitting them and the diseases they may The biology of erotic arousal seems to be similar for men cause through a society. These varied and wide-ranging and women, and descriptions of what it is like to be in an functions of and consequences for courtship and coition erotically aroused state are not gender specific (see Chapter mean that society tries to control the processes with customs 9 for further discussion). What then distinguishes erotic and laws (see Chapter 15). These then of course form part experiences in different individuals and genders? of the cultural inheritance that we learn as part of the gender stereotype of our society. Sexuality can be classified by the stimulus of The relationship between sex, gender and reproduction erotic arousal raised in this section will be revisited in many chapters later in this book. Now, however, we will complete our A commonly used system for classifying sexuality uses the preliminary consideration of sex, reproduction and gender object of sexual arousal as its starting point. Examples of by looking at the relationship of all three to sexuality. such a classification are shown in Table 2.2. Four things are striking about the contents of this table. First, there is a wide range of erotically arousing stimuli. Sexuality involves the erotic It is important to note that they are not necessarily mutually As mentioned in the previous section, courtship and coition exclusive. For example, a person may be aroused by both can involve intense and pleasurable sexual fantasies and men and women (bisexual), or by the opposite sex and Table 2.2 A classification system for sexualities. Classification of person Object causing arousal aroused Comments Person of opposite sex Heterosexual Social norm in most cultures Person of same sex Homosexual Acceptable in some forms in many societies; illegal or disapproved in others Immature person Paedophiliac Generally unacceptable Inanimate objects Paraphiliac Acceptable if not causing harm to others or distress to paraphiliac him- or herself Excrement Coprophiliac Generally disapproved of Wearing clothing of other gender Fetishistic transvestite Often confused with transgendered but is not a gender issue; may be accepted or ridiculed Watching others naked and/or engaged in sex Voyeur Broadly disapproved of unless ‘formalized’ or paid for Self displaying naked or engaged in sex Exhibitionist Broadly disapproved of unless ‘formalized’ or paid for Receiving or inflicting pain during sex Sadomasochist Recently held to be illegal in Europe  32 C HA P T E R 2 by objects or cross-dressing, or be sadomasochistic with the accepted, encouraged and celebrated. Similarly, paedo- same and/or opposite sex partner(s). The sexuality of philia has been, and still is, variously defined according to humans is complex. Moreover, the stimuli of erotic arousal a wide range in the age of sexual consent in different socie- may change for an individual with age, experience or social ties—both historical and contemporaneous. Heterosexual- expectation. So this labelling system is imperfectly rigid, ity, although a social norm in most societies, is circumscribed and the use of labelling as a shorthand can be misleading. heavily by restrictions on its expression in many, for Second, the stimuli are a mixture of objects, people and example within marriage, caste or ethnic group or by the activities and in some cases are described in terms of how relative age differentials of the partners. The social regula- they are used erotically but in others are not. When we deal tion of sexual expression is usually strict, whether by law with the sexual, there are two levels of description. There or social sanction. In many cases, it is so strict that individu- is the inner world of conscious arousal, imagination and als will hide or deny any sexual feelings that do not conform fantasy: this is usually given the name sexual identity, akin to approved sexual stereotypes, or may only express those to the conceptual inner state of gender identity we described feelings covertly. This strong social and self-censorship earlier. It is an acknowledgement by a person of their own makes research in the area of sexuality very difficult. People state of being as a sexual individual. Their own state may may lie, distort or remember selectively in retrospective or may not fit with the categories used in Table 2.2, although studies using questionnaires or interviews. Even in pro- most people will tend to use the labels that society provides spective studies, the behaviour and attitudes observed and for them. Thus, someone might say ‘I am a heterosexual/ recorded may reflect a strong impact of social expectations, homosexual/bisexual being’: that would be the verbal as we will see in the next two sections, which consider how expression of their sexual identity. This inner world may we acquire sexual identities. or may not be expressed through behaviour and sexual attitudes. Society usually has a clear expectation of how Genetics, brain anatomy, androgens and social learning people with different sexualities will behave and what their have all been implicated in the formation of sexualities attributes will be, a sexual stereotype, and this will be absorbed as a part of the sexual identity of people. Given the wide range of erotic stimuli, it would seem very Third, most of the stimuli clearly have nothing to do unlikely that there is a direct genetic basis for our sexuali- with procreative sex, since procreation is impossible or ties. It is difficult to see why evolution should have selected unlikely in the context of arousal by them. This emphasizes genes for fetishistic transvestism. It would be more reason- the clear separation of reproductive and erotic activities able to expect that evolution might have selected genes that can be observed in humans compared with other that encouraged sexual arousal in general and by the oppo- mammals in which reproduction and sexual arousal (espe- site sex in particular, since that would presumably promote cially in females) are very closely co-regulated (see Chapter the most effective transmission of those same genes to 8). In this regard humans resemble their closest evolution- future generations. So might there be something qualita- ary relatives among the higher primates and especially tively different about the basis of sexual arousal by people chimpanzees and bonobos. Thus, these species show quite as stimuli as opposed to by objects or situations? There is clearly that sexual interactions, both within and between little clear evidence on this point. However, just as in sexes and across age groups, can have a social role in addi- humans there appears to be considerable emancipation of tion to a sexual role. Genital showing and looking, touching our gender from our genes, such that social learning plays and rubbing, erection and mounting are commonly a larger role, so the same may have happened with our observed between individuals of the same sex, and are seen sexuality. There may be evolutionary advantages to flexi- as pleasurable and reassuring. Such same sex interactions ble and adaptive social and sexual structures that came are often called socio-sexual to distinguish them from the with this emancipation. Thus, whether or not there are eroto-sexual interactions between males and females, genetic or anatomical correlates and even causes of human although it is unclear how real this distinction is. The main sexualities, there seems likely to be an element of social point to understand is that sexual stimulation can form part learning too. As with gender identity, it is difficult to dis- of the social cement for social species. entangle the threads. Fourth, the social acceptability of different sexual stimuli Twin and familial studies have suggested that there varies with the stimuli, the type of person involved and the may be a genetic element in the establishment of our society in which they are experienced. Thus, homosexual sexuality—a finding much trumpeted in the popular press. acts between men have been viewed variously as essential, However, the results are far from decisive. The studies desirable, acceptable, immoral, illegal and pathological in have focused almost exclusively on the question of how different cultures and at different times, whereas those male homosexuality is determined. Monozygotic twins are between women have been ignored, ridiculed, politicized, reported to show a higher concordance of homosexuality  G E N D E R A ND SEXU AL ITY 33 than same-sex dizygotic twins. However, this finding does tion towards other women, most such women have a not demonstrate a ‘gene for sexuality’. Indeed, although heterosexual attraction to men. Numerous other women some familial studies have suggested that some homo- with no evidence of androgen exposure are attracted to sexual men are more likely to carry a particular set of women. Conversely, gay men show no evidence of reduced genetic markers on the X chromosome, none of these results androgens in comparison with heterosexual men. So andro- has been confirmed in other studies. Caution is required in gens seem unlikely to cause lesbianism, although they interpreting these sorts of genetic study of complex behav- might predispose to it indirectly, and lack of androgens is ioural traits. Thus, genetically more similar individuals are unlikely to cause male homosexuality. likely to share common experiences because they have So where does social learning fit? There is some evidence similar characteristics. This might predispose them to from work on paraphilias and fetishisms relating sexual responses more likely to lead to development of a particu- arousal experiences in early childhood to the stimuli likely lar sexuality. Imagine that our sexuality is learnt in early to arouse in the adult: associative learning. Children do childhood. The way in which it is learnt may depend on show evidence of arousal, such as phallic erection, from an the maturation of the nervous system as well as the social early age, and seem to derive pleasure from phallic stimu- surroundings. Imagine a gene or genes that advanced lation. It is possible that the coincidence of arousal with an slightly the maturation of one part of the nervous system emotionally charged event or object in childhood might over another part. That might change the learning pattern lead to the association of eroticism with that event or object and so influence the probability of a particular sexuality in later life. However, the evidence on this point is far from developing. This hypothetical scenario is presented to illus- clear, and we simply do not know how we become eroti- trate that, although there must be a genetic influence on cized to particular stimuli. The question of social learning sexuality, this does not mean that there is a genetic cause. in the development of sexuality is considered further in the The origins of sexuality are likely to be more complex and next section. multifactorial. A second line of evidence comes from studies on the The relationship between sexuality and gender structure of the brain. Earlier, examples were given of sug- gested sexual dimorphism in brain structure and organiza- Highly gendered societies, in which heterosexuality is the tion in humans. There are reports that the 3rd interstitial social norm and homosexuality is disapproved of, place a nucleus of the anterior hypothalamus (INAH3), which is strong emphasis on the link between gender and hetero- larger in men than in women, is of intermediate size in the sexuality. Thus, an integral part of being feminine is to be brains of self-declaring homosexual men. However, the attracted to men and of being masculine is to be attracted number of men in the studies is small and the overlap in to women. A heterosexual identity thus becomes subsumed the size values between gay men and non-gay men is too into a gender identity such that the two are conflated con- great to be significant in some studies. The validity of these ceptually. This conflation is evident in the sexual stereo- much publicized claims needs to be established more care- types of traditional Judaeo-Christian-Islamic societies. fully. If they do prove to be true, then the origins and time Thus, masculine men are seen as sexually dominant, active, of development of the size differences must be established. insertive and initiating whereas feminine women are sexu- At present, the evidence certainly does not warrant any ally passive, receptive and submissive. Deviations from suggestion that size differences in hypothalamic nuclei these stereotypes are stigmatized, witness the stereotypes either cause or are caused by homosexuality. There are no of the sexually passive, effeminate and ‘unmanned’ gay experimental data from animals to suggest a direct rela- and the sexually aggressive, masculine and defeminized tionship between this area of the brain and something as lesbian. However, in practice heterosexual individuals complex as homosexual orientation and behaviour. Indeed, show a much wider range of astereotypical sexual behav- studies in animals (see Chapter 8) suggest this to be very iours and, as we have already seen, heterosexuality need unlikely, as this hypothalamic area appears to be much not be ‘pure’ but can coexist within an individual with more concerned with the organization of copulatory wider sexual interests such as sadomasochism, paraphilias reflexes than with the expression of partner preference. and bisexuality. Moreover, although some gay men and Since, in animals, some hypothalamic nuclei differ in size lesbians may have insecure gender identities as men and as a result of perinatal androgen exposure, is there any women and may indeed conform to effeminate and butch evidence linking exposure to androgens to sexual attraction stereotypes, respectively, many others, especially those towards women? We have the same problems here that we who are confident of their homosexuality (are ‘out’), do not. encountered when considering androgens and gender There are many gay men who are both homosexual and development. However, although women who have adre- masculine, and lesbians who are both homosexual and nogenital syndrome do show a higher incidence of attrac- feminine. Insecurity of gender identity for homosexuals is,  34 C HA P T E R 2 of course, a likely outcome in a society in which sexual little evidence that any one of these actually causes each of and gender stereotypes are conflated and variation from us to have a particular sexual identity. The fact that differ- accepted gender and sexual stereotypes is stigmatized. In ent societies construct different systems of sexual stereo- other societies, in which this conflation of gender and sexu- types and that these become absorbed (internalized) ality does not occur, there appears little problem in mascu- through social learning into each individual’s sexual iden- line men and feminine women expressing homosexual tity implies that social learning must play a large part in emotions and behaviour. In this regard, the transgendered the construction of sexuality, perhaps building on or inter- are again instructive. Both male-to-female and female-to- acting with the various influences of genes and hormones male transgendered individuals may find men, women or to affect brain function and structure. both sexually arousing. Thus, a transgendered individual It is perhaps not surprising that the relatively simple of the male sex with a feminine gender identity may find rules governing the development of sex differences in the men sexually attractive, in which case he is homosexual behaviour of rodents cannot easily be applied to primates before surgery and hormone treatment and she is hetero- and humans. The finding in animals that exposure to sexual afterwards. Trans people emphasize the importance androgens during a critical period of early life both alters of uncoupling sexuality from gender conceptually, even if the structure of the brain and affects patterns of sex- in Judaeo-Christian and Islamic cultures they have been dependent and sexual behaviour in adulthood, does not conflated socially. find a simple counterpart in monkeys or humans. In both The conflation of sexuality and gender further complicates the latter species, behavioural evidence of the effects of study of the possible social learning of sexuality. A number exposure of the fetal female brain to androgens is present of retrospective studies suggest that gays and lesbians recall in the form of sexually dimorphic childhood behaviour, but having more ambiguous gender experiences in childhood affected individuals can display apparently typical pat- than do self-defining heterosexual men and women. For terns of feminine gender identity and heterosexual behav- example, gay men recalled playing with girls and girls’ toys iour as adults. Sex assignment at birth and the subsequent and games, and lesbians recalled being tomboyish. However, gender-specific patterns of social behaviours and interac- retrospective studies suffer from the dangers of selective tions that flow from gender and sexual stereotypes seem to recall and denial, which, as we saw earlier, is a dangerous play a major role in shaping behavioural dimorphism, possibility in an area as sensitive as this. Prospective studies gender identity and sexual identity. of children referred to clinicians precisely because they were In these first two chapters, we have examined both the displaying gender-atypical play patterns have shown that as foundations of sexual reproduction in mammals and the adults these individuals manifest a higher incidence of many and wide-ranging aspects of the social life of homosexuality than control children. It is difficult to know mammals that flow from them. In subsequent chapters, we how to interpret these findings, especially as they are based will look at the physiological processes regulating fertility on children so seriously different (or perceived to be so) as to and sexual behaviour that result in conception, pregnancy, be referred to a gender clinic. Precisely because society, parturition, lactation and maternal care. parents and children themselves associate gender and sexual stereotypes, they are more likely to develop in tandem: there F UR T HE R R E AD I N G is after all the basis of a socially learned element to each. The results do not mean that they must develop in tandem or that General reading having one identity causes a person to have the other (in Golombok S, Fivush R (1994) Gender Development. Cambridge either direction). University Press, Cambridge (an excellent account of gender development, despite its age). Summary Hinde R (1996) Gender differences in close relationships. In: Social Interaction and Personal Relationships (ed. D. Miell & R. Dallos), We do not understand how people acquire a sexual iden- pp. 324–335. Sage, London (an account of gender relationship tity. Indeed, our understanding of the complex nature of patterns by an eminent behavioural scientist). sexual identity is incomplete. Our systems for classifying Hines M (2004) Brain Gender. Oxford University Press, Oxford (a sexuality are at best approximate and still based largely on measured account of the behavioural and neuroanatomical a historical view of all sexual deviation from a narrowly studies on sex and gender). defined heterosexuality as being pathological and socially undesirable. This is not a helpful starting point for looking More advanced reading (see also Boxes) at the natural expression of sexuality. There undoubtedly Bancroft J (1989) Human Sexuality and its Problems. Churchill are influences of genes, hormones, brain structure and Livingstone, London (despite its age, a rich repository in which social learning on how our sexualities develop, but there is to dip).  G E N D E R A ND SEXU AL ITY 35 KEY LEARNING POINTS Gender is a system of classification based on sex. Babies of different sexes seem to show different A gender stereotype is a set of social beliefs about what behaviours quite early in neonatal life, but it is not clear it means to be a man or a woman. It may include whether the origin of these differences is endocrine, appearance, behaviour, role (social, sexual and genetic, socially learnt or a mixture of all three. employment) and emotional and attitudinal attributes. It Human infants establish a gender identity by 3 years of provides a shorthand for classifying peop