The view that humans comprise only two types of beings, women and men, a framework that is sometimes referred to as the "gender binary," played a profound role in shaping the history of psychological science. In recent years, serious challenges to the gender binary have arisen from both academic research and social activism. This review describes 5 sets of empirical findings, spanning multiple disciplines, that fundamentally undermine the gender binary. These sources of evidence include neuroscience findings that refute sexual dimorphism of the human brain; behavioral neuroendocrinology findings that challenge the notion of genetically fixed, nonoverlapping, sexually dimorphic hormonal systems; psychological findings that highlight the similarities between men and women; psychological research on transgender and nonbinary individuals' identities and experiences; and developmental research suggesting that the tendency to view gender/sex as a meaningful, binary category is culturally determined and malleable. Costs associated with reliance on the gender binary and recommendations for future research, as well as clinical practice, are outlined. (PsycINFO Database Record

Sexual orientation typically describes people's sexual attractions or desires based on their sex relative to that of a target. Despite its utility, it has been critiqued in part because it fails to account for non-biological gender-related factors, partnered sexualities unrelated to gender or sex, or potential divergences between love and lust. In this article, I propose Sexual Configurations Theory (SCT) as a testable, empirically grounded framework for understanding diverse partnered sexualities, separate from solitary sexualities. I focus on and provide models of two parameters of partnered sexuality--gender/sex and partner number. SCT also delineates individual gender/sex. I discuss a sexual diversity lens as a way to study the particularities and generalities of diverse sexualities without privileging either. I also discuss how sexual identities, orientations, and statuses that are typically seen as misaligned or aligned are more meaningfully conceptualized as branched or co-incident. I map out some existing identities using SCT and detail its applied implications for health and counseling work. I highlight its importance for sexuality in terms of measurement and social neuroendocrinology, and the ways it may be useful for self-knowledge and feminist and queer empowerment and alliance building. I also make a case that SCT changes existing understandings and conceptualizations of sexuality in constructive and generative ways informed by both biology and culture, and that it is a potential starting point for sexual diversity studies and research.

Hormones, and hormone responses to social contexts, are the proximate mechanisms of evolutionary pathways to pair bonds and other social bonds. Testosterone (T) is implicated in tradeoffs relevant to pair bonding, and oxytocin (OT) and arginine vasopressin (AVP) are positively tied to social bonding in a variety of species. Here, we present the Steroid/Peptide Theory of Social Bonds (S/P Theory), which integrates T and peptides to provide a model, set of predictions, and classification system for social behavioral contexts related to social bonds. The S/P Theory also resolves several paradoxes apparent in the literature on social bonds and hormones: the Offspring Defense Paradox, Aggression Paradox, and Intimacy Paradox. In the S/P Theory, we partition aggression into antagonistic and protective aggression, which both increase T but exert distinct effects on AVP and thus social bonds. Similarly, we partition intimacy into sexual and nurturant intimacy, both of which increase OT and facilitate social bonds, but exert distinct effects on T. We describe the utility of the S/P Theory for classifying 'tricky' behavioral contexts on the basis of their hormonal responses using partner cuddling, a behavior which is assumed to be nurturant but increases T, as a test case of the S/P Theory. The S/P Theory provides a comparative basis for conceptualizing and testing evolved hormonal pathways to pair bonds with attention to species, context, and gender/sex specificities and convergences.

A set of computerized tasks was used to investigate sex differences in the speed and accuracy of emotion recognition in 62 men and women of reproductive age. Evolutionary theories have posited that female superiority in the perception of emotion might arise from women's near-universal responsibility for child-rearing. Two variants of the child-rearing hypothesis predict either across-theboard female superiority in the discrimination of emotional expressions (battachment promotionQ hypothesis) or a female superiority that is restricted to expressions of negative emotion (bfitness threatQ hypothesis). Therefore, we sought to evaluate whether the expression of the sex difference is influenced by the valence of the emotional signal (Positive or Negative). The results showed that women were faster than men at recognizing both positive and negative emotions from facial cues, supporting the attachment promotion hypothesis. Support for the fitness threat hypothesis also was found, in that the sex difference was accentuated for negative emotions. There was no evidence that the female superiority was learned through previous childcare experience or that it was derived from a sex difference in simple perceptual speed. The results suggest that evolved mechanisms, not domaingeneral learning, underlie the sex difference in recognition of facial emotions.

Women are underrepresented in the professoriate compared to men; this study was designed to examine whether systemic barriers associated with parenting discourage women from pursuing academic careers. Data from 468 female and male graduate students were collected through an online questionnaire. More men than women intend to pursue academic careers. Parenting and mobility issues-but not research or teaching issues-were more negatively associated with entering the professoriate for women than for men. However, women were not more interested in having children than men were. Results support the hypothesis that women self-select away from academia in response to perceived systemic barriers related to parenthood. To ensure quality and equity in academia, universities should enact policy that addresses the realities of childbearing and childrearing women.