Sex-Linked Behavior: Evolution, Stability, and Variability

Agent-based models of the cultural evolution of occupational gender roles

The causes of sex differences in human behaviour are contested, with 'evolutionary' and 'social' explanations often being pitted against each other in the literature. Recent work showing positive correlations between indices of gender equality and the size of sex differences in behaviour has been argued to show support for 'evolutionary' over 'social' approaches. This argument, however, neglects the potential for social learning to generate arbitrary gender segregation. In the current paper we simulate, using agent-based models, a population where agents exist as one of two 'types' and can use social information about which types of agents are performing which 'roles' within their environment. We find that agents self-segregate into different roles even where real differences in performance do not exist, if there is a common belief (modelled as priors) that group differences may exist in 'innate' competence. Facilitating role changes such that agents should move without cost to the predicted highest-rewards for their skills (i.e. fluidity of the labour market) reduced segregation, while forcing extended exploration of different roles eradicated gender segregation. These models are interpreted in terms of bio-cultural evolution, and the impact of social learning on the expression of gender roles.

Sex and gender in neurodevelopmental conditions

Health-related conditions often differ qualitatively or quantitatively between individuals of different birth-assigned sexes and gender identities, and/or with different gendered experiences, requiring tailored care. Studying the moderating and mediating effects of sex-related and gender-related factors on impairment, disability, wellbeing and health is of paramount importance especially for neurodivergent individuals, who are diagnosed with neurodevelopmental conditions with uneven sex/gender distributions. Researchers have become aware of the myriad influences that sex-related and gender-related variables have on the manifestations of neurodevelopmental conditions, and contemporary work has begun to investigate the mechanisms through which these effects are mediated. Here we describe topical concepts of sex and gender science, summarize current knowledge, and discuss research and clinical challenges related to autism, attention-deficit/hyperactivity disorder and other neurodevelopmental conditions. We consider sex and gender in the context of epidemiology, behavioural phenotypes, neurobiology, genetics, endocrinology and neighbouring disciplines. The available evidence supports the view that sex and gender are important contributors to the biological and behavioural variability in neurodevelopmental conditions. Methodological caveats such as frequent conflation of sex and gender constructs, inappropriate measurement of these constructs and under-representation of specific demographic groups (for example, female and gender minority individuals and people with intellectual disabilities) limit the translational potential of research so far. Future research and clinical implementation should integrate sex and gender into next-generation diagnostics, mechanistic investigations and support practices.

Fairly Criticized, or Politicized? Conflicts in the Neuroscience of Sex Differences in the Human Brain

Investigations of sex differences in the human brain take place on politically sensitive terrain. While some scholars express concern that gendered biases and stereotypes remain embedded in scientific research, others are alarmed about the politicization of science. To help better understand these debates, this review sets out three kinds of conflicts that can arise in the neuroscience of sex differences: academic freedom versus gender equality; frameworks, background assumptions, and dominant methodologies; and inductive risk and social values. The boundaries between fair criticism and politicization are explored for each kind of conflict, pointing to ways in which the academic community can facilitate fair criticism while protecting against politicization.

The Interactions Among Sexual Orientation, Masculine and Feminine Gender Role Orientation, and Facets of Sociosexuality in Young Heterosexual and Homosexual Men

The present study investigated the functional relationships among sexual orientation, masculine and feminine gender role orientation, and sociosexual orientation in 282 heterosexual and 282 homosexual young men. Homosexual men reported significantly more pronounced sociosexual behavior (d = 0.65) and desire (d = 0.31). Furthermore, homosexual men were characterized by lower masculine (d =-0.26) and higher feminine (d = 0.38) gender role orientation. Latent variable analyses revealed that homosexual men as well as more masculine men, irrespective of their sexual orientation, had more uncommitted sexual relations and more unrestricted sociosexual attitudes. A similar pattern could be identified for sociosexual desire. While homosexual men were more unrestricted in their sociosexual desire, this also held for more feminine men in general. Overall, findings indicated that homosexual orientation is positively associated with sociosexual orientation. In addition, masculine/feminine gender role orientations exert differential influences on the three facets of sociosexuality independent of sexual orientation.

The rhetorical use of B. F. Skinner in evolutionary psychology

This article examines Skinner’s often neglected ideas about evolution, which he returns to in his final academic paper. I attempt to square Skinner’s advocacy for evolutionary explanation, including his efforts to reconcile biological, individual, and cultural adaptation, with how he is framed and critiqued by a school of evolutionary psychologists who attribute to Skinner a blank slate, or so-called standard social science model, view of the mind. I argue that characterizing Skinner in this manner is inconsistent with his evolutionary writings and ignores Skinner’s explicit disavowals of such interpretations. I then discuss Skinner’s evolutionary views in light of contemporary evolutionary theories of human psychology. I also compare the reception to evolutionary psychology and Skinner within the field more generally and conclude by discussing the proposal that evolutionary psychology should be considered a new paradigm for psychology, a claim that seems to follow from evolutionary psychologists’ caricature of Skinner.

Autism spectrum disorder: An examination of sex differences in neuropsychological and self-report measures of executive and non-executive cognitive function

LAY ABSTRACT

Research comparing females and males with a diagnosis of autism suggests that there are sex differences in some characteristics such as behaviour regulation. One area not studied in detail is whether females and males with autism perform differently in tests of cognitive ability. The results of previous research are quite mixed. One explanation may be that some research comparing females and males with autism did not include a neurotypical control group for comparison. As a result, it is not clear whether the sex differences in cognitive ability observed in people with autism are similar to differences between neurotypical males and females. To better understand whether there are unique differences between males and females with autism, it is important to also compare them with neurotypical males and females. In our research, we included a neurotypical group and compared males and females with and without a diagnosis of autism. We found that the sex differences in autism are similar to what we observe in males and females without autism. Our study showed that compared with males, females (with and without autism) do better in assessments of processing speed, cognitive flexibility, verbal learning and memory and semantic fluency. Our results suggest that although females show different cognitive performance to males, these sex differences were not specific to the group with a diagnosis of autism.

Gender Beneath the Skull: Agency, Trauma and Persisting Stereotypes in Neuroepigenetics

Epigenetics stands in a complex relationship to issues of sex and gender. As a scientific field, it has been heavily criticized for disproportionately targeting the maternal body and reproducing deterministic views of biological sex (Kenney and Müller, 2017; Lappé, 2018; Richardson et al., 2014). And yet, it also represents the culmination of a long tradition of engaging with developmental biology as a feminist cause, because of the dispersal of the supposed 'master code' of DNA among wider cellular, organismic and ecological contexts (Keller, 1988). In this paper, we explore a number of tensions at the intersection of sex, gender and trauma that are playing out in the emerging area of neuroepigenetics - a relatively new subfield of epigenetics specifically interested in environment-brain relations through epigenetic modifications in neurons. Using qualitative interviews with leading scientists, we explore how trauma is conceptualized in neuroepigenetics, paying attention to its gendered dimensions. We address a number of concerns raised by feminist STS researchers in regard to epigenetics, and illustrate why we believe close engagement with neuroepigenetic claims, and neuroepigenetic researchers themselves, is a crucial step for social scientists interested in questions of embodiment and trauma. We argue this for three reasons: (1) Neuroepigenetic studies are recognizing the agential capacities of biological materials such as genes, neurotransmitters and methyl groups, and how they influence memory formation; (2) Neuroepigenetic conceptions of trauma are yet to be robustly coupled with social and anthropological theories of violence (Eliot, 2021; Nelson, 2021; Walby, 2013); (3) In spite of the gendered assumptions we find in neuroepigenetics, there are fruitful spaces - through collaboration - to be conceptualizing gender beyond culture-biology and nature-nurture binaries (Lock and Nguyen, 2010). To borrow Gravlee's (2009: 51) phrase, we find reason for social scientists to consider how gender is not only constructed, but how it may "become biology" via epigenetic and other biological pathways. Ultimately, we argue that a robust epigenetic methodology is one which values the integrity of expertise outside its own field, and can have an open, not empty mind to cross-disciplinary dialogue.

On the Functional Relationships Among Sexual Orientation, Masculine and Feminine Gender Role Orientation, and Sociosexual Orientation in Young Heterosexual and Lesbian Women

The present study investigated the mutual interplay of sexual orientation, masculine and feminine gender role orientation, and sociosexual orientation in young women. To ensure cross-sample validity, 323 heterosexual women and 323 lesbian women, ranging in age from 18 to 29 years, were matched for possible confounding variables. Lesbian women scored significantly higher (d = 0.27) on the Desire subscale of the Revised Sociosexual Orientation Inventory, but not on the Behavior (d = 0.07) and Attitude subscales (d = 0.11). Concerning gender role orientation, heterosexual women were characterized by significantly higher scores on the Femininity scale (d = 0.20), whereas lesbian women showed more pronounced masculine gender role orientation (d = 0.16). Structural equation modeling revealed two functionally distinct relationships between sexual orientation and sociosexuality, on the one hand, and between gender role orientation and sociosexuality, on the other hand. Sociosexual desire was exclusively associated with a woman's sexual orientation with no indication of any mediating effect of gender role orientation. Sociosexual behavior was positively related to a woman's level of masculine gender role orientation, while sociosexual attitude was positively associated with masculine and negatively associated with feminine gender role orientation, irrespective of sexual orientation.

The Relationship Between Gender Role Orientation and Sexual Health Care in Taiwanese Nurses: A Structural Equation Model

Introduction

Patients’ sexual concerns are private, sensitive issues, and providing sexual health care (SHC) is a legitimate area of concern for the nursing practice.

Aims

This study tests a structural equation model for factors that affect SHC among Taiwanese nurses.

Methods

A cross-sectional study was performed between August 2014 and July 2015. A total of 471 registered nurses from a medical center in Taiwan were enrolled in this study. All nurses participated anonymously and completed 3 questionnaires: Nursing Attitude in Sexual Health Care scale, Nursing Intervention in Sexual Health scale, and Gender Role Orientation scale. The Permission-Limited Information-Specific Suggestions-Intensive Therapy model based on scale was application, and theory of planned behavior was used to examine the relationship of these 3 scales in nurses.

Main Outcome Measures

SHC surveys were developed for nurses. These valid and reliable instruments included Nursing Attitude in Sexual Health Care, Nursing Intervention in Sexual Health, and Gender Role Orientation.

Results

The fitted structural equation model was valid. The construct reliability of latent variables ranged from 0.730 to 0.942, which met the requirement of 0.70. The attitude about SHC (β = 0.182, P < .001), subjective norms on SHC (β = 0.146, P < .001), and confidence about SHC (β = 0.583, P < .001) had significant effects on the behavioral intention to provide SHC. Subsequently, the behavioral intention to provide SHC had a significant, direct effect on the behavioral frequency of providing SHC (β = 0.356, P < .001). However, gender role orientation was not significantly associated with behavioral intention and behavioral frequency to provide SHC.

Conclusions

The good fit for the structural equation model suggests that the predictors of behavioral intention and behaviors of providing SHC include attitude, subjective norms, and perceived control. The stronger behavioral intention of providing SHC resulted in a higher frequency of providing SHC. However, the relationship between gender role orientation and SHC had no significant effect.

Huang C-Y, Liou C-F, Lee S-H, et al. The Relationship Between Gender Role Orientation and Sexual Health Care in Taiwanese Nurses: A Structural Equation Model. Sex Med 2020;8:565–573.

Sex-related differences in self-care behaviors of adults with type 2 diabetes mellitus

PURPOSE

To describe sex-related differences in self-care; to identify determinants of self-care according to sex, and to investigate how sex interacts with the effect of clinical and socio-demographic variables on self-care in adults with Type 2 Diabetes Mellitus (T2DM).

METHODS

Cross-sectional multicentre study with a consecutive sampling recruitment strategy, enrolling 540 adults with T2DM at six outpatient diabetes services. Clinical and socio-demographic variables were collected by medical records. Self-care maintenance, monitoring, management, and confidence were measured by the self-care of diabetes inventory.

RESULTS

Females reported higher disease prevention behaviors (P < 0.001), health-promoting behaviors (P < 0.001), body listening (P < 0.001), and symptom recognition (P = 0.010), but lower health-promoting exercise behaviors (P < 0.001). Determinants of self-care were different in male and female patients, where the role of task-specific self-care confidence predicted self-care monitoring (RR = 0.98; P < 0.001) and management (RR = 0.99; P < 0.001) among males, while persistence self-care confidence predicted self-care maintenance (RR = 0.97; P = 0.016) and management (RR = 0.99; P = 0.009) among females.

CONCLUSIONS

Males and females differently perform self-care. Self-care confidence plays a different role predicting self-care behaviors in males and females. Future research should longitudinally describe self-care and its determinants in males and females with T2DM. Sex-specific self-care confidence interventions should be developed to improve self-care in male and female patients with T2DM.

The Complex Relationships between Sex and the Brain

In the past decennia, our understanding of the sexual differentiation of the mammalian brain has dramatically changed. The simple model according to which testosterone masculinizes the brain of males away from a default female form, was replaced with a complex scenario, according to which sex effects on the brain of both females and males are exerted by genetic, hormonal, and environmental factors. These factors act via multiple partly independent mechanisms that may vary according to internal and external factors. These observations led to the "mosaic" hypothesis-the expectation of high variability in the degree of "maleness"/"femaleness" of different features within a single brain. Here, we briefly review animal data that form the basis of current understanding of sexual differentiation; present, in this context, the results of co-analyses of human brain measures obtained by magnetic resonance imaging or postmortem; discuss criticisms and controversies of the mosaic hypothesis and implications for research; and conclude that co-analysis of several (preferably, many) features and going back from the group level to that of the individual would advance our understanding of the relations between sex and the brain in health and disease.