Sexual Shape Research Articles

Age Structure, Body Size, and Sexual Dimorphism in a High-Altitude Population of Pelophylax ridibundus (Pallas, 1771)

This study aimed to describe the morphological characteristics and age structure of a P. ridibundus population sampled from a high altitude. For this purpose, a total of 54 adult frogs (33 males and 21 females) were collected from Şavşat district, Artvin province, Türkiye. The samples were aged based on skeletochronology method. Furthermore, von Bertalanffy growth curve models were constructed using SVL and weight data. To assess sexual size and shape dimorphism, the measurements of 23 different morphological characters were analyzed using univariate and multivariate statistical techniques. The mean SVL and weight were found to be 78.05 mm and 60.87 g for males and 93.95 mm and 109.61 g for females. The mean age was 3.67 years and 4.05 years for males and females, respectively. The maximum age was found to be 6 years for both sexes. Growth curve models revealed a significant relationship between age, SVL, and weight. A clear female-biased sexual size dimorphism was found in all morphological characters. However, SVL-adjusted values indicated that males had larger head and limb structures resulting from evolutional and sexual pressures associated with reproduction and male–male competition. The shape dimorphism was found only in forelimbs, and it was male-biased and was related to clasping in amplexus.

The conjugal order and long-term reintegration in Northern Uganda. How ideas of sexuality and patrilineality shape reintegration processes of men, women and children born in captivity

ABSTRACT Research on the reintegration of ex-combatants has mostly focused on a short period after the end of conflict. Building on this observation, I analyse the long-term reintegration processes of formerly abducted by the Lord’s Resistance Army (LRA) in Northern Uganda from a feminist perspective. Specifically, I explore how long-term reintegration differs for returning men, women and children born in captivity (CBC). To understand these long-term processes, it is crucial to analyse the wider societal order into which returnees reintegrate. I argue that in Northern Uganda a conjugal order centred around ideas of sexuality/marriage and patrilineality shapes the different reintegration experiences of returning women, men and CBC. I find that gender affects both short-term and long-term reintegration, with returning women and their children encountering significantly more difficulties than returning men. Interestingly, male CBC transitioning into adulthood are confronted with more problems related to the conjugal order than female CBC. Overall, my findings suggest that reintegration is an open, dynamic, and intergenerational process that cannot be confined to a fixed time frame.

Population bottlenecks and sexual recombination shape diatom microevolution.

Diatoms are single-celled organisms that contribute approximately 20% of the global primary production and play a crucial role in biogeochemical cycles and trophic chains. Despite their ecological importance, our knowledge of microevolution is limited. We developed a model using the SLiM evolutionary framework to address this knowledge gap. As a reference, we used the diatom Pseudo-nitzschia multistriata, which has been extensively studied in the Gulf of Naples. Our model recapitulates what we observe in natural populations, with microevolutionary processes that occur annually during a three-stage bloom phase. Interestingly, we found that non-bloom phases allow the population to maintain sex-generated diversity produced during blooms. This finding suggests that non-bloom phases are critical to counteract bloom-related pressures and mitigate genetic divergence at the species level. Moreover, our model showed that despite the consistent genetic differentiation during bloom phases, the population tends to return to pre-bloom states. While our model is limited to neutral dynamics, our study provides valuable insights into diatoms' microevolution, paving the way to explore the ecological implications of the life history dynamics of these organisms.

Sexual dimorphism in the Hungarian golden jackal population: analysing body and skull size and shape

AbstractDefining species within the Canidae family is challenging due to morphological convergence, behavioral plasticity, traditional taxonomic limitations, and possible hybridisation. This challenge is timely with the recent population and range expansion of the golden jackal (Canis aureus). Exploring their morphological data and sexual dimorphism is essential for identifying factors driving their success in new habitats. The proven hybridization of golden jackals with dogs and wolves may affect species description, population dynamics, and genetic diversity, impacting conservation strategies. This study, for the first time, conducts a morphometric analysis of golden jackals in Somogy County, Hungary, to prove sexual size dimorphism (SSD) in body and skull and sexual shape dimorphism (SShD) in skull across juvenile and adult age groups. 719 golden jackals (362 females and 357 males) were collected between January 2021 and January 2023. Descriptive statistics revealed significant SSD in body and skull measurements among both age groups, with males generally larger than females, particularly in body mass (11.72% in juveniles and 13.37% in adults). Most skull dimensions differed significantly between sexes and age groups, except for foramen magnum height, foramen magnum width, and postorbital breadth among juveniles and foramen magnum height and postorbital breadth among adults. We used principal component analyses (PCA) on raw dimension data and the log shape ratio method to extract shape information. Linear discriminant analysis (LDA) explored skull SShD between sexes. Notably, our study achieved over 71% accuracy in sex classification, illustrating the clear presence of SShD of the skull in golden jackals across both age groups. Our study provides a comprehensive database of golden jackals in the overpopulated Hungarian habitat, which will be helpful for further research on ecology, behavior, and conservation management.

Intersectionality, gender norms, and young adolescents in context: a review of longitudinal multicountry research programmes to shape future action.

Discriminatory gender norms can intersect and interact with other dimensions of discrimination-such as age, race, ethnicity, disability, education status, and sexual orientation-to shape individuals' experiences and impact their health and wellbeing. This interaction is referred to as intersectionality. Although the theory has been in circulation since the late 1980s, only recently has it gained traction in low-income and middle-income settings, and it has yet to fully penetrate global research on adolescence. The social and structural intersectional drivers of adolescent health and wellbeing, particularly during early adolescence (age 10-14 years), are poorly understood. The evidence base for designing effective interventions for this formative period of life is therefore relatively small. In this Review, we examine how gender intersects with other forms of disadvantage in the early stages of adolescence. Analysing data from hybrid observation-intervention longitudinal studies with young adolescents in 16 countries, our aim is to inform the health and wellbeing of girls and boys from a range of social contexts, including in conflict settings. Adolescents' perceptions about gender norms vary by context, depend on individual opinion, and are shaped by socioecological drivers of gender inequalities in health. Shifting those perceptions is therefore challenging. We argue for the importance of applying an intersectionality lens to improve health and wellbeing outcomes for young adolescents and conclude with five practical recommendations for programme design and research.

Sexual Dimorphism: The Interrelation of Shape and Color

Sex-typicality displayed as sexual dimorphism of the human face is a key feature enabling sex recognition. It is also believed to be a cue for perceiving biological quality and it plays an important role in the perception of attractiveness. Sexual dimorphism of human faces has two main components: sexual shape dimorphism of various facial features and sexual color dimorphism, generally manifested as dimorphism of skin luminance, where men tend to be darker than women. However, very little is known about the mutual relationship of these two facets. We explored the interconnection between the dimorphism of face shape and dimorphism of face color in three visually distinct populations (Cameroonian, Czech, and Vietnamese). Our results indicated that populations which showed a significant dimorphism in skin luminance (Cameroon, Vietnam) had low levels of sexual shape dimorphism, while a population with higher levels of sexual shape dimorphism (Czech Republic) did not exhibit a significant dimorphism of skin luminance. These findings suggest a possible compensatory mechanism between various domains of sexual dimorphism in populations differing in the levels of shape and color dimorphism.

Male proboscis monkey cranionasal size and shape is associated with visual and acoustic signalling

The large nose adorned by adult male proboscis monkeys is hypothesised to serve as an audiovisual signal of sexual selection. It serves as a visual signal of male quality and social status, and as an acoustic signal, through the expression of loud, low-formant nasalised calls in dense rainforests, where visibility is poor. However, it is unclear how the male proboscis monkey nasal complex, including the internal structure of the nose, plays a role in visual or acoustic signalling. Here, we use cranionasal data to assess whether large noses found in male proboscis monkeys serve visual and/or acoustic signalling functions. Our findings support a visual signalling function for male nasal enlargement through a relatively high degree of nasal aperture sexual size dimorphism, the craniofacial region to which nasal soft tissue attaches. We additionally find nasal aperture size increases beyond dental maturity among male proboscis monkeys, consistent with the visual signalling hypothesis. We show that the cranionasal region has an acoustic signalling role through pronounced nasal cavity sexual shape dimorphism, wherein male nasal cavity shape allows the expression of loud, low-formant nasalised calls. Our findings provide robust support for the male proboscis monkey nasal complex serving both visual and acoustic functions.

The Role of Partner Gender: How Sexual Expectations Shape the Pursuit of an Orgasm Goal for Heterosexual, Lesbian, and Bisexual Women

Previous research has established that gendered sexual scripts shape sexual behavior. This study seeks to expand prior work on orgasm disparities for women across sexual orientations by exploring the role of partner gender. Across two studies, we examined how the gender of women’s sexual partners influenced their orgasm goal pursuit. We compared lesbian and heterosexual women’s experience with their most recent partner in Study 1, and experimentally compared bisexual women partnered with a woman or a man in a hypothetical sexual encounter in Study 2. In both studies, women reported higher clitoral stimulation and orgasm expectations when partnered with a woman compared to a man. Moreover, partner gender had a significant indirect effect on women’s orgasm goal pursuit through clitoral stimulation and expectations for orgasm. These results suggest that sexual scripts associated with partner gender play a key role in the orgasm gap for women who have sex with men.

“It’s Not, Can You Do This? It’s… How Do You Feel About Doing This?” A Critical Discourse Analysis of Sexuality Support After Spinal Cord Injury

Previous research has indicated that healthcare support for sexuality after spinal cord injury appears to be neglected or inadequately provided. The perspectives of people living with spinal cord injuries regarding what is lacking and what support they would like to be provided, and why, has yet to be explored. This paper uses critical theory to explore how societal constructs of sexuality and disability shape how sexuality is supported after a spinal cord injury. To do this, we conducted in-depth semi-structured interviews with 11 people with a spinal cord injury from Australia, the United Kingdom, and the United States. We drew from the works of various critical disability theorists to analyze what discourses underpinned the experiences people with spinal cord injuries had when receiving sexuality support. Analysis suggested that the following discourses were apparent: (1) broken bodies require repair, (2) sex is penetration, ejaculation then reproduction, and (3) sexual autonomy is required. Findings indicated healthcare professionals need to recognize people with spinal cord injuries as sexual beings with a diverse range of desires, lives, relations, and bodies. Provision of individualized comprehensive high-quality sexuality support is therefore warranted. To achieve this, healthcare professionals should aim to be aware of, and mitigate, ableist and normative assumptions.

Characterizing the vaginal microbiome in a sexually fluid primate (Pan paniscus).

While there have been recent breakthroughs in human vaginal microbiome research, very few non-human primate (NHP) vaginal microbiome studies exist due to difficulty in obtaining samples. In this study, we sought to: (1) characterize the bonobo vaginal microbiota for the first time, and (2) determine the relationship between vaginal pH and swelling size. During a 21-day study period, we collected observational data and 71 vaginal swabs from three cohoused adult females at the Ape Cognition and Conservation Initiative. After filtering and classification, a total of 3452 amplicon sequence variants were recruited from 12 vaginal samples. The most dominant phylum represented was Actinobacteria, and the most abundant genera were Gardnerella, Atopobium, and Prevotella. The mean pH score was 6.1 (range: 5.1-7.0), and pH levels varied with relative swelling size. This is the first study to examine the vaginal microbial composition in this species, and it conforms to previous NHP studies in that there was not the same bacterial dominance of Lactobacillus spp. often highlighted in human vaginal microbiota studies. Our findings suggest there may be other factors contributing to the protection of the bonobo vaginal environment, but future analysis of a larger sample is needed to fully understand how sociality and sexuality shape vaginal microbiota and host health.

How Organizational Responses to Sexual Harassment Claims Shape Public Perception

Sexual harassment remains pervasive in the workplace. Complementing past research examining the intra-organizational effects of sexual harassment, this paper investigates its extra-organizational consequences by considering reputational damage organizations can suffer from sexual harassment claims. Four experiments (NTotal = 1,534) show that even a single sexual harassment claim can damage public perception of gender equality of an organization, which reduces organizational attractiveness. However, an organizational response characterized by proactive consideration of the claimant (compared to no mention of sexual harassment, mention of sexual harassment with no response, or a minimizing response to a sexual harassment claim) fully restores, and sometimes even increases, public perceptions of the organization’s commitment to due process and gender equality. Implications for theory and practice are discussed.

Ctenocephalides orientis and Ctenocephalides felis in Thailand: Head geometry by species, sex and geography.

Fleas in the genus Ctenocephalides serve as biological vectors or intermediate hosts of microorganisms such as bacteria, rickettsia, protozoa and helminths. Ctenocephalides felis has a worldwide distribution, while C. orientis has long been considered as a subspecies of C. felis in Asia. To help the morphological recognition of these two species and further explore their differences, we used the geometric morphometric approach applied to the head. Both sexes were examined. Five anatomical landmarks of the head were used, and to capture the curvature of the front head, 10 semilandmarks were added. There was a consistent difference in species classification accuracy when considering landmarks only versus their combination with semilandmarks, suggesting the importance of the curve of the head as a taxonomic signal. Using or not the labels in the reclassification analyses, the head shape allowed by itself almost perfect recognition of the two species, in both sexes, even after adjustment for prior probabilities. The same approach disclosed a high level of sexual size and shape dimorphism in both species. The contribution of size variation to the discrimination by shape was much more important between sexes (from 27% to 45%) than between species (from 0.7% to 7.1%). Nevertheless, in our data, size never could represent a way to reliably recognise the sex of an individual, even less its species. Geographical variation in head shape could only be explored for the C. orientis sample. No significant correlation of morphometric variation with geography could be detected, which would be consistent with gene flow between Thai provinces. The geometric morphometric approach of the flea head, when it incorporates head curves, is a promising tool for rapid, economical, and accurate species and sex identification. It is, therefore, a useful tool for future epidemiological and demographic studies.

Sexual Dimorphism in <i>Testudo graeca zarudnyi</i> (Testudines: Testudinidae) from Yazd Province, Central Iran

To investigate morphological traits of the poorly known Zarudny’s tortoise, Testudo graeca zarudnyi Nikolsky, 1896, which has only been reported from Iran so far, we have conducted morphometric analysis to test sexual differences (sexual size and shape dimorphism, SSD) in Marvar Prohibited Hunting Area (central Iran). Our findings showed that males have wider carapace and larger hind limbs; while, females have longer plastron. This pattern has resulted in shape differences with males; that is, have more domed and wider carapace than to the females. Generally, Females are larger than males we will discuss it as a force to fecundity selection. The results showed that this subspecies does not follow Rench’s rule which argues that males are larger than females.

Sexual Dimorphism in the Limb Bones of Asiatic Toad (Bufo gargarizans) in Relation to Sexual Selection.

Sexual dimorphism is often considered to be the result of differences in the intensity of sexual selection between sexes. From this point of view, the sexual dimorphism of the limb bones of the Bufo gargarizans in southwest China was studied. Results showed that the fore- and hindlimb skeletons of this species were sexually dimorphic in anatomy. The humerus, radioulna, and total lengths of the forelimb skeleton of males were substantially longer than those of females, but the hand length of males was smaller than that of females. Several other features of males, such as deltoid and medial crest areas and humerus and radioulnar weights, were also significantly larger than those of females. The femoris, tibiofibula, talus-calcaneus, and foot lengths; total hindlimb skeleton length; and femoral upper crest areas of males were significantly greater than those of females. However, no significant intersexual difference in femoris and tibiofibular weights was observed. These findings suggested that robust forelimb bones and long hindlimb bones could contribute to the mating success of males; if so, sexual selection promotes the evolution of sexual size and shape dimorphism in the limb bones of the B. gargarizans.

How sexual and natural selection interact and shape the evolution of nests and nesting behaviour in fishes.

Among ray-finned fishes that provide parental care, many spawn in constructed nests, ranging from bowls, burrows and ridges to nests made of algae or bubbles. Because a nest by definition is a construction that enhances the nest-builder's fitness by helping it meet the needs of the developing offspring, nest-building behaviour is naturally selected, as is a preference for spawning with mates that provide well-built nests. However, nest-building behaviour can also be sexually selected, when nest traits increase mating success, protect against sperm competition or nest take-overs by conspecifics. Here, we offer a systematic review, with examples of how competition for sites and location of fish nests relates to sexual selection. We examine direct and indirect benefits of mate choice linked to nest traits, and different types of nests, from a sexual selection perspective. Nest-related behaviours are often under both natural and sexual selection, and we disentangle examples where that is the case, with special attention to females. We highlight some taxa in which nest building is likely to be sexually selected, but lack of research has left them uninvestigated. Some of them are established aquarium species, making them particularly amenable for future research. Finally, we compare with arthropods, amphibians and birds. This article is part of the theme issue 'The evolutionary ecology of nests: a cross-taxon approach'.

Sexual shape dimorphism in Bufo verrucosissimus (Pallas, 1814) from Lake Borçka Karagöl, Türkiye

Sexual dimorphism, i.e., differences in morphology between sexes of a species caused by intersexual differences in the strength or direction of sexual or natural selection, is prevalent throughout the animal kingdom. Contrary to differences in body size, little is known about sexual shape dimorphism in anurans. Here we investigated intersexual shape differences in Bufo verrucosissimus (Pallas, 1814) by taking 27 linear measurements to characterize body morphology of 23 males and 23 females. Relative to their overall body size, males had longer limbs and larger eyes, while females displayed larger parotoid glands and had wider heads. We speculate that these intersexual differences may have arisen due to differences in natural and sexual selection regimes acting on males and females, especially during foraging, mate searching, or intrasexual competition.

Shan Male Migrants’ Engagement with Sex Work in Chiang Mai, Thailand, Pre- and Post-Pandemic

ABSTRACT Thailand’s sex industry for same-gender sexual services for men has seen a shift to a predominantly migrant workforce, particularly in northern Thailand. The majority of male sex workers in Chiang Mai are ethnic Shan nationals from neighboring Myanmar. This research explores the lives of Shan migrant male sex workers, their adaptations to and survival strategies in the pre- and post-pandemic periods. The paper employs an intersectionality approach to understand how the intersections of class, gender, ethnicity, legal status, and the larger context of transnational sexual commodification shape the ways Shan migrant men engage in sex work. Based on two sets of data collected before and after the Covid-19 pandemic, the research explores how Shan male sex workers utilize their sexualities and other forms of capital while managing a plethora of risks.

Sexual dimorphism in the badlands cricket (Orthoptera, Gryllinae, Gryllus personatus)

Sexual dimorphism (SD) is a common phenomenon in sexual species and can manifest in a variety of ways. Sexual size dimorphism (SSD) is commonly investigated, but it can be confounded with sexual shape dimorphism (SShD) if multivariate measures of size are not used. Univariate studies may also overestimate the prevalence or direction of SSD when the sexes are strikingly different in shape, which may be an issue in taxa such as Orthoptera and other terrestrial arthropods where maximum body size is strongly constrained. Here we tested for the occurrence of both SSD and SShD in the badlands cricket Gryllus personatus (Orthoptera, Gryllinae). We measured four body size dimensions—maxillae span, head width, pronotum length, and mean hind femur length—and used multivariate methods to test whether male and female adult badlands crickets were sexually dimorphic in size and/or shape. All the univariate dimensions were sexually dimorphic, with males having wider heads and maxillae than females and females having longer pronota and hind femora than males, which indicates SShD. However, multivariate methods failed to detect SSD, instead confirming that the sexes primarily differ in body shape. We show how a simple ratio of head width to pronotum length captures SShD in badlands crickets and apply it to iNaturalist, a citizen science platform, to broaden our findings. We propose that orthopterists studying SD minimally measure head width, pronotum length, and hind femur length as a standard that will allow a more repeatable and generalizable assessment of the prevalence and direction of both SSD and SShD.

Marginalize or Valorize: A Two-Case Study of Parental Essentialism and Fathers’ Social Location

The idea that children need a mother and a father to thrive is a hegemonic ideology of parenting, yet research finds that children do equally well in families with two parents of any gender. Prior research has not addressed how social location shapes parents’ engagement with gender essentialist ideologies of parenting. Filling this gap, we analyze ethnographic and interview data based on the experiences of poor fathers of color and mostly white, wealthy gay fathers. This two-case study uniquely reveals how class, race, and sexuality shape fathers’ relationships to parental essentialism. Fathers experience it as either a source of empowerment that valorizes them as worthy parents or a source of marginalization that denies their ability to raise healthy children. We theorize how this dual response reveals the salience and dangers of essentialist discourses in spaces where men grapple with gendered and heteronormative ideologies of masculinity, fatherhood, and families.

“Because He Is Gay”: How Race, Gender, and Sexuality Shape Perceptions of Judicial Fairness

Previous articleNext article No Access"Because He is Gay": How Race, Gender, and Sexuality Shape Perceptions of Judicial FairnessAna Bracic, Mackenzie Israel-Trummel, Tyler Johnson, and Kathleen TiplerAna Bracic Search for more articles by this author , Mackenzie Israel-Trummel Search for more articles by this author , Tyler Johnson Search for more articles by this author , and Kathleen Tipler Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The Journal of Politics Just Accepted Sponsored by the Southern Political Science Association Article DOIhttps://doi.org/10.1086/723996 Views: 54Total views on this site HistoryAccepted December 12, 2022 © 2023 Southern Political Science Association. All Rights reserved.PDF download Crossref reports no articles citing this article.