Sexual Shape Research Articles

Intersectional Masculinities in Heteronormative Spaces: Exploring Power and Privilege amongst Gay Men in South Africa

This paper discusses the power differentials between various gay men that shape the construction of multiple unequal gay masculinities in South Africa. I argue that there is no single homogenous gay masculinity but multiple gay masculinities informed by various intersections that privilege some gay men while disadvantaging others. Considering the historical and continuing unequal racial divisions, class differences, power differentials, and gender normativity, this paper presents an intersectional analysis of three gay masculinities: White gay masculinity, Black middle-class gay masculinity, and Black working-class township gay masculinities. Intersections of race, gender, sexuality, class, and space shape power differentials amongst gay men in the same manner as heterosexual men, and through a review of literature, the paper demonstrates how intersectionality can help develop nuanced understandings of gay masculinities in South Africa. The paper highlights the need to interrogate the multifaceted nature of South African gay masculinities through an intersectional lens.

‘Let the ladies know’: queer women’s perceptions of how gender and sexual orientation shape their eating and weight concerns

This exploratory study aimed to describe the lived experiences of queer women affected by eating and weight-related concerns. Qualitative data from young queer women (n = 105; Age = 23.6 ± 3.4 years) with eating and weight-related concerns in response to open-ended questions related to the influence of gender identity and body image on weight concern, behaviours, and perception were analysed using reflexive thematic analysis. Nine themes were created to describe participants’ experiences: (1) compensation for other internalised stigma, (2) to suppress body parts that can be gendered or sexualised, (3) comparisons to romantic partners’ bodies, (4) media representations, (5) queer signalling, (6) queerness as protective, (7) gender expression and dysphoria, (8) societal expectations of women’s bodies, and (9) internalisation of body/beauty ideals. Seven sub-themes were created to represent beauty ideals for specific subcultural communities (e.g. femme, butch). Findings suggest that queer women attribute individual, interpersonal and social factors to weight concerns, behaviours and perceptions. Findings highlight how complex tensions between the beauty/body ideals experienced in cisheteronormative and queer spaces influence eating and weight concerns among queer women. Gender, sexual orientation and subcultural ideals intersect in important ways, and may be useful to consider when screening, treating and preventing eating and weight concerns among queer women.

Sexual size and shape dimorphism, and allometric scaling in the pupal and adult traits of Eristalis tenax.

The patterns and amount of variation in size, shape, and/or life history traits between females and males are fundamentally important to gain the comprehensive understanding of the evolution of phenotypic diversity. In addition, the covariation of phenotypic traits can significantly contribute to morphological diversification and sexual dimorphism (SD). Using linear and geometric morphometrics, 237 Eristalis tenax specimens sampled from five populations were, therefore, comparatively assessed for the variation in sexual size dimorphism (SSD), sexual shape dimorphism (SShD), and life history traits, as well as for trait covariation (ontogenetic and static allometry). Pupal body, adult wing, and body mass traits were analyzed. Female-biased SSD was observed for pupal length, width, and centroid size, adult wing centroid size, mass, wing loading, and wing area. Conversely, pupal length/width ratio, developmental time, and mass were not found to be sexually dimorphic. Next, wing SShD, but not pupal body SShD was revealed, while allometry was found to be an important "determinant of SD" at the adult stage, with only a minor impact at the pupal stage. By comparing the patterns of covariance (based on allometric slope and intercept) between respective body mass and morphometric traits of pupae and adults, greater variation in allometric slopes was found in adult traits, while static allometries of the two stages significantly differed, as well. Finally, the results indicate that changes in the allometric intercept could be an important source of intraspecific variation and SD in drone fly adults.

The Role of Sexual and Romantic Attraction in Human Mate Preferences

ABSTRACT Sex differences in mate preferences are ubiquitous, having been evidenced across generations and cultures. Their prevalence and persistence have compellingly placed them in the evolutionarily adaptive context of sexual selection. However, the psycho-biological mechanisms contributing to their generation and maintenance remain poorly understood. As such a mechanism, sexual attraction is assumed to guide interest, desire, and the affinity toward specific partner features. However, whether sexual attraction can indeed explain sex differences in partner preferences has not been explicitly tested. To better understand how sex and sexual attraction shape mate preferences in humans we assessed how partner preferences differed across the spectrum of sexual attraction in a sample of 479 individuals that identified as asexual, gray-sexual, demisexual or allosexual. We further tested whether romantic attraction predicted preference profiles better than sexual attraction. Our results show that sexual attraction accounts for highly replicable sex differences in mate preferences for high social status and financial prospects, conscientiousness, and intelligence; however, it does not account for the enhanced preference for physical attractiveness expressed by men, which persists even in individuals with low sexual attraction. Instead, sex differences in physical attractiveness preference are better explained by the degree of romantic attraction. Furthermore, effects of sexual attraction on sex differences in partner preferences were grounded in current rather than previous experiences of sexual attraction. Taken together, the results support the idea that contemporary sex differences in partner preferences are maintained by several psycho-biological mechanisms that evolved in conjunction, including not only sexual but also romantic attraction.

Taphonomy of the teleost Tselfatia formosa Arambourg, 1943 from Vallecillo, NE Mexico.

The platy limestone deposit of Vallecillo in northeastern Mexico is dated to the early-middle Turonian (Late Cretaceous) and known to contain a variety of well-preserved vertebrate fossils. One of the most common fish species is the teleost Tselfatia formosa. A review of 149 individuals reveals the presence of two types of body shapes (diamond-shaped and torpedo-shaped individuals) which is interpreted as sexual shape dimorphism (SSD). A unimodal size distribution illustrates a dominance of diamond-shaped specimens, but both body shape types are present in small (young) and big sized (old) individuals. The abundance of well-articulated and complete specimens suggests that T. formosa populated deep levels of the water column, which excluded buoyancy and flotation as well as carcass disintegration near the surface. The reconstruction of the dorsal and anal fins suggests the presence of a membrane between each fin ray and allows for ecological comparison of T. formosa with modern fan fishes.

Where spirituality and religion meet gender and sexuality: Toward a research agenda for intersectional marketing theory

During a roundtable discussion at the 2022 GENMAC Conference, a group of researchers specializing in religiosity and spiritual consumption, using examples from their own fieldwork, reflected on how (i) researchers’ subject positioning—including their gender and sexuality—shape fieldwork in multifaceted manners; (ii) investigations of religious/spiritual fields would benefit from a heightened sensitivity to issues of gender and sexuality; and (iii) greater sensitivity to aspects of religion and/or spirituality can help gender and sexuality scholars better understand consumers and markets. Based on the above, in this commentary paper, we call for intersectional reflexivity, attention to vulnerability and discomfort during fieldwork, and critical sensitivity to the religious “context of context” during theorization. Furthermore, we argue that specific spiritual/religious imaginaries can foster new research approaches that can contribute to more nuanced fieldwork and theorization in marketing and consumer research.

Prevent2Protect Project: Regulatory Focus Differences in Sexual Health Knowledge and Practices

The way people perceive risks and make decisions about their health is regulated by two motivational systems—prevention of harm or promotion of pleasure. People more focused on prevention strive to avoid negative outcomes and enact more health-protective behaviors. In contrast, people more focused on promotion strive to attain positive outcomes and take more risks with their health. Building upon recent evidence extending this framework to sexual behaviors and health, we conducted a pre-registered online survey (OSF) with Portuguese and Spanish adults (N = 742; Mage = 31.42, SD = 9.16) to examine whether self-reported STI knowledge and sexual health practices differ based on predominant regulatory focus. This study was part of the Prevent2Protect project (OSF). Results showed that prevention-focused participants had heard about more STIs and retrieved more of their knowledge from scientific sources but had been tested for fewer STIs in the past. In contrast, promotion-focused participants indicated they had specific knowledge about more STIs, retrieved more of their knowledge from medical and peer sources, and had been tested for more STIs in the past. They also reported more frequent STI testing, using free testing facilities or asking their family practice doctor to get tested, more routine sexual health check-ups, and more use of other contraceptive methods, such as birth control pills. These results remained unchanged after controlling for demographic differences. Overall, our findings showed that different motives in sexuality shape sexual health knowledge and sexual health practices.

ECR Spotlight – Marco Graziano

ABSTRACT ECR Spotlight is a series of interviews with early-career authors from a selection of papers published in Journal of Experimental Biology and aims to promote not only the diversity of early-career researchers (ECRs) working in experimental biology during our centenary year, but also the huge variety of animals and physiological systems that are essential for the ‘comparative’ approach. Marco Graziano is first author on ‘ Frequency-dependent viscosity of salmon ovarian fluid has biophysical implications for sperm–egg interactions’, published in JEB. Marco conducted the research described in this article while a PhD candidate in Matthew Gage's lab at University of East Anglia, UK. He is now a senior postdoctoral associate in the lab of Simone Immler at University of East Anglia, investigating how sexual and natural selection shape eco-evolutionary processes at the gametic level: before, during and after the reproductive event.

A peek behind the curtain: An integrative review of sexual harassment of nursing students on clinical placement.

This integrative review aimed at systematically searching, analysing and synthesising multiple sources of evidence, to build a temporal understanding of nursing students' experiences of sexual harassment whilst on clinical placement, and to discuss the social context which enables this. Sexual harassment is highly prevalent in workplaces globally. Contemporary social understandings contextualise sexual harassment as a significant form of interpersonal violence. This is the first literature review to go beyond prevalence to synthesise the experience, implications and responses to sexual harassment encountered by student nurses on clinical placement. Whittemore and Knafl's (2005) integrative review methodology is used to structure a rigorous analysis and synthesis of evidence. The PRISMA checklist supported sound reporting of the search strategy. Three databases (CINAHL, Scopus and Medline) were searched using a Boolean strategy. Papers with a significant focus on sexual harassment of nursing students in the clinical setting were included with no limitation on publication date. Papers were excluded if they were not published in English or were only published as abstracts. A synthesis of 26 papers demonstrated that sexual harassment has significant impacts on student nurses and the nursing profession. The intimacy of close body care, dominant social perceptions of nursing as women's work and the sexualisation of nurses increase student vulnerability to sexual harassment. Workplace power imbalances further exacerbate sexual harassment and shape responses to incidents. Sexual harassment of nursing students is widespread and impacts student well-being and learning. Education is a strong protective factor and should target students, clinicians, clinical facilitators and academics. Attention to workplace culture, and processes that support disclosure and reporting, is also required to meaningfully address the sexual harassment of nursing students.

Sexual Dimorphism of the Human Scapula: A Geometric Morphometrics Study in Two Portuguese Reference Skeletal Samples

The estimation of biological sex is of paramount relevance in the analysis of skeletal remains recovered in forensic contexts. This study aims to assess sexual dimorphism for identification purposes, from two reference samples of the Portuguese population, and a depiction of the size- and shape-related sexual dimorphism of the human scapula using geometric morphometrics approaches. The sample comprised 211 individuals (100 males and 111 females). A generalized Procrustes analysis (GPA) was performed for shape analyses, a principal component analysis (PCA) and a Procrustes ANOVA were implemented on the GPA transformed variables, and a discriminant analysis was used to assess the cross-validated accuracy of sex estimates. The data showed that male scapulae were larger, with medial and lateral curves more pronounced and an inferior angle more acute than females. The males and females were classified with low accuracy (66.82% and 65.88% for landmarks and semi-landmarks data) based on shape. Combining size and shape variables improved the accuracy of the prediction using landmarks data (80.09%). A combination of both variables might improve the chances of the geometric morphometrics methodology in correctly estimating the sex of unidentified individuals, especially if the skeletal elements show low sexual shape dimorphism.

Climate shapes patterns of sexual size and shape dimorphism across the native range of the green anole lizard,Anolis carolinensis(Squamata: Dactyloidae)

AbstractGeographical variation in sexual size dimorphism (SSD) can result from the combined effects of environmental and sexual selection. To understand the determinants of SSD across geographical landscapes, we tested for relationships between SSD and climatic variables in the widespread lizard Anolis carolinensis. To distinguish alternative hypotheses for observed patterns of variation in SSD, we also examined sex-specific patterns of body size evolution and asked whether SSD was associated with certain patterns of sexual shape dimorphism. We found strong evidence for Rensch’s rule (an increase in male-biased SSD with average body size) in A. carolinensis and evidence for the reversed version of Bergmann’s rule (an increase in body size towards warmer environments) in males. Across populations, SSD was positively related to temperature; however, female body size was not related to any climatic variable, suggesting that the latitudinal gradient of SSD might be driven by a gradient in the intensity of sexual selection acting on males. Sexual size dimorphism was positively correlated with sexual dimorphism in head shape and negatively correlated with limb length dimorphism, suggesting that sexual selection in males might drive the evolution of SSD and that differences in size and limb shape between sexes might represent alternative strategies to avoid competition for the same resources.

Influence of the nutritional status on facial morphology in young Japanese women

Evidence regarding the possible influence of nutritional status on the facial morphology has thus far been insufficient. We examined whether or not the physical body compositions and dietary behaviors were correlated with any morphological characteristics of the face. One hundred and fifteen young Japanese women participated. Variables representing the dietary behaviors were extracted from self-reported survey data, and corresponding three-dimensional (3D) facial images and body compositions were examined. Multivariate analyses identified significant relationships between the nutritional status and facial topography (p < 0.05). The clustering method revealed the existence of three dietary condition patterns (“balanced diet”, “high-calorie-diet” with obesity tendency, and “imbalanced low-calorie-diet” with sarcopenic obesity tendency). Among these three patterns, a round face (increased facial width; analysis of variance [ANOVA], p < 0.05) was observed in the high-calorie-diet pattern, while the imbalanced low-calorie-diet pattern showed a more masculine face (increased face height, decreased eye height, increased non-allometric sexual shape differences; ANOVA, p < 0.05), thus suggesting the possibility of sex-hormonal influences. In summary, the body composition and dietary behaviors were found to influence the facial morphology, and potential biological influences were discussed.

How perceptions of masculinity and intimate sexual relationships shape men’s experiences of paying for sex: A qualitative exploration

This qualitative study explores how perceptions of masculinity, sexual intimate relationships and sex-for-pay (SFP) shape the experiences of men who pay women for sex (MPWS). Semi-structured interviews were conducted with 16 Israeli MPWS. Participants were recruited through an STD community clinic, an anonymous online survey, ads posted in online forums for MPWS, and an organization for the abolition of prostitution. The findings offer a complex understanding of the experiences of MPWS, based on the intersections between their views of sexuality within long-term intimate relationships, and their perceptions of the acceptability of SFP within dominant discourses of masculinity. The findings comprise four experiential patterns of the multi-layered practice of paying for sex: Agonizing, Ambivalent, Intermittent and Simultaneous.

Sexual and natural selection interplay in sexual head shape dimorphism of two sympatric racerunners (Squamata: Lacertidae)

Both natural and sexual selection can shape sexual dimorphism. However, determination of the contribution of these selection pressures is challenging. In lizards, sexual selection can contribute to the larger head size of males than that of females. However, males and females can also diverge in their head size to prey on different food resources under conditions of limited resources (and/or high competitors). Here, 109 individuals from two sympatric desert racerunners (Eremias grammica: 28 males and 30 females; Eremias velox: 25 males and 26 females) were studied to determine their sexual head shape (head length, width, and depth). Additionally, 191 and 169 feces samples of E. grammica and E. velox, respectively, were collected to assess the niche divergence hypothesis (a proxy for natural selection). We found that both species had dimorphic head shapes; male heads (i.e., length, width, and depth) were significantly larger than female heads (P &amp;lt; 0.05, in all cases) in E. grammica, and male heads of E. velox were significantly longer than those of females (P &amp;lt; 0.05). Chi-square test revealed that there were significant differences in the proportion (Hymenopteran and Orthopteran) and sizes of prey type between the two sexes of E. grammica; conspecific males and females of E. velox differed in the proportion of Coleopteran and Hymenopteran prey. Both males and females of these two species had a high niche overlap index (range from ∼ 0.78 to 0.99) with each other. There were also significant differences in the sizes of the heads and prey between the two species (P &amp;lt; 0.05). However, the interspecific differences were mainly caused by interspecific male–male differences in morphological and prey traits. In summary, we believe that both natural (pressures from resource competition) and sexual selection drive sexual head shape dimorphism in these two sympatric lizards, owing to high food resource competition in arid regions. Therefore, head trait divergence can reduce competition by resulting in a preference for different prey types.

How Do Investigation Experiences Shape Views of the Police? Qualitatively Exploring Sexual Assault Survivors’ Interactions With Police Detectives and Subsequent Views of the Police

Little attention has been paid to views of the police among sexual assault survivors. Understanding views of the police among a large population of crime victims who have historically been silenced and mistreated by our criminal-legal system can help inform recent and ongoing conversations about police funding and criminal justice reform. Qualitative interview data from a community sample of sexual assault survivors explored how police-detective interactions during sexual assault investigations shape views of the police. Negative interactions led to negative views of the police and for some were based on a culmination of positive and negative experiences. I share recommendations for responding to sexual assault that consider sexual assault survivors’ experiences with and views of the police.

Skull ecomorphological variation of narwhals (Monodon monoceros, Linnaeus 1758) and belugas (Delphinapterus leucas, Pallas 1776) reveals phenotype of their hybrids.

Narwhals and belugas are toothed whales belonging to the Monodontidae. Belugas have a circumpolar Arctic and sub-Artic distribution while narwhals are restricted to the Atlantic Arctic. Their geographical ranges overlap during winter migrations in the Baffin Bay area (Canada/West Greenland) and successful interbreeding may occur. Here, we employed geometric morphometrics on museum specimens to explore the cranium and mandible morphology of a known hybrid (NHMD MCE 1356) and the cranium morphology of a putative hybrid (NHMD 1963.44.1.4) relative to skull morphological variation in the parental species. Specifically, we used 3D models of skulls from 69 belugas, 86 narwhals, and the two known/putative hybrids and 2D left hemi-mandibles from 20 belugas, 64 narwhals and the known hybrid. Skull shape analyses allowed clear discrimination between species. Narwhals are characterised by a relatively short rostrum and wide neurocranium while belugas show a more elongated and narrower cranium. Sexual size dimorphism was detected in narwhals, with males larger than females, but no sexual shape dimorphism was detected in either species (excluding presence/absence of tusks in narwhals). Morphological skull variation was also dependent on different allometric slopes between species and sexes in narwhals. Our analyses showed that the cranium of the known hybrid was phenotypically close to belugas but its 2D hemi-mandible had a narwhal shape and size morphology. Both cranium and mandible were strongly correlated, with the pattern of covariation being similar to belugas. The putative hybrid was a pure male narwhal with extruded teeth. Comparison of genomic DNA supported this result, and stable carbon and nitrogen isotope values suggested that the putative hybrid had a more benthic foraging strategy compared to narwhals. This work demonstrates that although the known hybrid could be discriminated from narwhals and belugas, detection of its affinities with these parental species was dependent on the part of the skull analysed.

An Overview of Interlocation Sexual Shape Dimorphism in Caquetaia kraussi (Perciformes: Cichlidae): A Geometric Morphometric Approach

C. kraussii is an endemic fish species from Colombia and Venezuela and represents a valuable food resource for local human communities. Due to its economic importance, the management and captive breeding of this species are of special interest. However, the anatomical similarities between sexes have been a problem for visual identification. It is also important to indicate that C. kraussii has cryptic morphological behavior between sexes, a topic that has been one of the main problems for the implementation of management plans. The following research studied individuals from three different localities along the Canal del Dique, Bolívar Department in Colombia, in which the body shape of C. kraussii was analyzed using geometric morphometric analysis. The analyses detected the presence of intralocality sexual dimorphism in two of the three localities analyzed, showing a low morphological variability among males, presenting conserved body shape, as well as a greater morphological disparity among females. This sexual shape dimorphism may be associated with the environmental variation among different locations. These results suggest the presence of two evolutionary forces acting asymmetrically between the sexes of C. kraussii, with males mostly subject to sexual selection pressure, while females are mainly subject to environmental pressures.

Sexual Identities and Reactions to Black Lives Matter.

IntroductionThis study traced sexuality differences in Black Lives Matter (BLM) approval before using theories of “political distinctiveness” to explain why sexuality differences occurred.MethodsA random sample of 3489 US adults completed the 2016 wave of the American National Election Survey (ANES) Time Series project. Ordinary least squares (OLS) regressions assessed differences in BLM support by reported sexual identity when adjusting for possibly relevant covariates.ResultsLesbians, gays, and bisexuals (LGB) backed BLM more than heterosexuals. Increased LGB support of BLM was driven by sexuality differences in racial backgrounds, marital statuses, perceptions of police biases, approval of Black empowerment, authoritarianism, and emotional bonds to people of color.ConclusionsSexual identities shape reactions to antiracist social movements. LGB alignment with BLM is partly due to sexual discrepancies in demographic qualities, group memberships, and the way sexual identities alter an awareness of social biases.Policy ImplicationsGreater LGB liberalism, plus the queer friendly nature of BLM, offers greater prospects in the creation and maintenance of intersectional social justice movements that seek to improve the lives of racial and sexual minorities.

The shell measurements that best describe sexual dimorphism in the spur-thighed tortoise &lt;em&gt;Testudo graeca&lt;/em&gt; from Algeria

Due to phenotypic plasticity and sex-biased selective pressures, intraspecific variation in tortoise morphology is usually assessed by studying sexual dimorphism. However, inferences may differ based on the choice of shell size measurements for analyses. In this work, we identified linear measurements that best describe sexual dimorphism for the spur-thighed tortoise Testudo graeca whitei. We assessed 34 carapace and plastron measurements in 67 individuals (24 males, 43 females) in a population at the natural Mergueb site located on the central limit of the Algerian steppe. Twenty-two out of 34 measurements significantly showed sexual size dimorphism in ANOVA tests. When analyzing sexual shape dimorphism with ANCOVAs, nine measurements showed no shared allometry with the measurements used as covariates to correct by size. Meanwhile, 17 out of the remaining 23 measurements showed significant differences in shape. PCA analyses similarly described T. graeca’s sexual dimorphism. In general, females tend to be bigger than males, especially in central scutes what is probably linked with clutch sizes commitments. On the other hand, males are larger-sized in anterior and posterior scutes, probably as a result of courtship, male fighting and copulation. Some of the analyzed measurements are revealed as being especially adequate for further studying the geographical variation of sexual dimorphism in Testudo graeca

Morphological variation of the maxilla in modern humans and African apes

Differences in morphology among modern humans and African apes are frequently used when assessing whether hominin fossils should be attributed to a single species or represent evidence for taxic diversity. A good understanding of the degree and structure of the intergeneric, interspecific, and intraspecific variation, including aspects such as sexual dimorphism and age, are key in this context. Here we explore the variation and differences shown by the maxilla of extant hominines, as maxillary morphology is central in the diagnosis of several hominin taxa. Our sample includes adults of all currently recognized hominine species and subspecies, with a balanced species sex ratio. In addition, we compared the adults with a small sample of late juveniles. The morphology of the maxillae was captured using three-dimensional landmarks, and the size and shape were analyzed using geometric morphometric methods. Key observations are that 1) the maxillae of all extant hominine species and subspecies show statistically significant differences, but complete separation in shape is only seen at the genus level; 2) the degree of variation is not consistent between genera, with subspecies of Gorilla being more different from each other than are species of Pan; 3) the pattern of sexual shape dimorphism is different in Pan, Gorilla, and Homo, often showing opposite trends; and 4) differentiation between maxillary shapes is increased after adjustment for static intraspecific allometry. These results provide a taxonomically up-to-date comparative morphological framework to help interpret the hominin fossil record, and we discuss the practical implications in that context.