Sex-specific transgenerational effects of diet on offspring life history and physiology.

Dietary variation in males and females can shape the expression of offspring life histories and physiology. However, the relative contributions of maternal and paternal dietary variation to phenotypic expression of latter generations is currently unknown. We provided male and female Drosophila melanogaster grandparents with diets differing in sucrose concentration prior to reproduction, and similarly subjected their grandoffspring to the same treatments. We then investigated the phenotypic consequences of this dietary variation among the grandsons and granddaughters. We observed transgenerational effects of dietary sucrose, mediated through the grandmaternal lineage, which mimic the direct effects of sucrose on lifespan, with opposing patterns across sexes; low sucrose increased female, but decreased male, lifespan. Dietary mismatching of grandoffspring-grandparent diets increased lifespan and reproductive success, and moderated triglyceride levels of grandoffspring, providing insights into the physiological underpinnings of the complex transgenerational effects on life histories.

The future of sex and gender in research.

Our understanding of sex and gender evolves. We asked scientists about their work and the future of sex and gender research. They discuss, among other things, interdisciplinary collaboration, moving beyond binary conceptualizations, accounting for intersecting factors, reproductive strategies, expanding research on sex-related differences, and sex's dynamic nature.

Sex contextualism in laboratory research: Enhancing rigor and precision in the study of sex-related variables.

Understanding sex-related variation in health and illness requires rigorous and precise approaches to revealing underlying mechanisms. A first step is to recognize that sex is not in and of itself a causal mechanism; rather, it is a classification system comprising a set of categories, usually assigned according to a range of varying traits. Moving beyond sex as a system of classification to working with concrete and measurable sex-related variables is necessary for precision. Whether and how these sex-related variables matter-and what patterns of difference they contribute to-will vary in context-specific ways. Second, when researchers incorporate these sex-related variables into research designs, rigorous analytical methods are needed to allow strongly supported conclusions. Third, the interpretation and reporting of sex-related variation require care to ensure that basic and preclinical research advance health equity for all.

Shirin Heidari.

Dr. Shirin Heidari is the lead author of the Sex and Gender Equity in Research (SAGER) guidelines. In this interview with Dr. Isabel Goldman at Cell, she discusses her research, GENDRO, the SAGER guidelines and importance of considering sex- and gender-related variables in research, and her work on sexual and reproductive health in forced displacement.

The history of sex research: Is "sex" a useful category?

The history of sex research demonstrates an ongoing coexistence of multiple, conflicting meanings of sex. This history raises questions for scientists about the deployment of a research variable that lacks precision. Cross-disciplinary collaboration between scientists and science and technology studies (STS) scholars offers a way to find solutions to this problem.

Sex and gender essentialism in textbooks.

Several widely used high school biology texts depart from established science.

Cancer and the family: Variations by sex and race/ethnicity.

BACKGROUND: Cancer affects patients and their families, but few data are available on factors associated with diversity of family structures among patients with cancer. Family is a source of both support and responsibility that must be understood to support patients and their families. METHODS: Pooled data (2004-2015) from the National Health Interview Study were used to compare characteristics of cancer survivors with and without minor children and differences by sex and race/ethnicity among survivors with minor children. RESULTS: 13.9% of cancer survivors have minor children in the household, and this experience is more likely for women and people who identify as other than non-Hispanic White. CONCLUSION: There are considerable differences by sex and race/ethnicity in the characteristics of cancer survivors with minor children. Clinicians should make consideration of family circumstances a routine part of their history. Doing so will help to identify potential sources of support and responsibility that may affect adherence.

Sexual cannibalism as a female resistance trait: a new hypothesis.

Female spiders and praying mantises are renowned for their cannibalism of male partners before, during, or after mating. While several hypotheses have been proposed to explain species-specific examples of sexual cannibalism, much variation remains unexplained, including why the timing of cannibalism varies across taxa. Here, I outline how sexually cannibalistic behavior could evolve via sexually antagonistic selection as a type of behavioral resistance to male-imposed mating costs, and how such a generalizable interpretation provides a framework for understanding the evolution of both sexual cannibalism in females and anti-cannibalistic traits in males. I discuss how differences between mating systems that physiologically constrain males to mate only once (monogyny) or twice (bigyny) and systems where the sexes can potentially mate multiply (polygyny and polyandry) are likely to influence how sexual conflict shapes cannibalistic behavior. I review key examples from the literature that suggest how sexually cannibalistic behavior might function as a female resistance trait and provide comprehensive predictions for testing this hypothesis empirically.

Sex diversity in the 21st century: Concepts, frameworks, and approaches for the future of neuroendocrinology.

Sex is ubiquitous and variable throughout the animal kingdom. Historically, scientists have used reductionist methodologies that rely on a priori sex categorizations, in which two discrete sexes are inextricably linked with gamete type. However, this binarized operationalization does not adequately reflect the diversity of sex observed in nature. This is due, in part, to the fact that sex exists across many levels of biological analysis, including genetic, molecular, cellular, morphological, behavioral, and population levels. Furthermore, the biological mechanisms governing sex are embedded in complex networks that dynamically interact with other systems. To produce the most accurate and scientifically rigorous work examining sex in neuroendocrinology and to capture the full range of sex variability and diversity present in animal systems, we must critically assess the frameworks, experimental designs, and analytical methods used in our research. In this perspective piece, we first propose a new conceptual framework to guide the integrative study of sex. Then, we provide practical guidance on research approaches for studying sex-associated variables, including factors to consider in study design, selection of model organisms, experimental methodologies, and statistical analyses. We invite fellow scientists to conscientiously apply these modernized approaches to advance our biological understanding of sex and to encourage academically and socially responsible outcomes of our work. By expanding our conceptual frameworks and methodological approaches to the study of sex, we will gain insight into the unique ways that sex exists across levels of biological organization to produce the vast array of variability and diversity observed in nature.

Representações sociais sobre maternidade na reprodução humana assistida: discursos de mulheres inférteis / Social representations of motherhood in assisted human reproduction: discourses of infertile women / Representaciones sociales de la maternidad en la reproducción humana asistida: relatos de mujeres infértiles

Este trabalho tem o objetivo de analisar as concepções de maternidade para mulheres inférteis de diferentes níveis socioeconômicos que estão em tratamento de reprodução assistida. Trata-se de um estudo qualitativo, descritivo, que utilizou como instrumento uma entrevista semiestruturada e contemplou temas como o significado de família, desejo/expectativas sobre filho e gestação e expectativas sobre a maternidade. Participaram da pesquisa 48 mulheres inférteis acima de 35 anos que usam tecnologias de reprodução assistida de alta complexidade em instituições privada e pública. Os dados foram tratados pela análise de conteúdo em que emergiram os temas: representações sociais da família; representações sociais da maternidade; expectativas com a gestação e os modelos maternos; e o filho imaginado. As participantes representaram a família de forma positiva, como um sistema de suporte, de fundação e origem de amor, configurando-a como um laço social. Por outro lado, as concepções de família com base na consanguinidade também estiveram presentes, representando a família pela perpetuação da espécie e pela importância do laço biológico. A maternidade foi marcada por significativa idealização, sendo vista como um papel gratificante e de realização da feminilidade. O peso da cobrança social para procriar também foi sentido como um dever a cumprir e que, na impossibilidade de se realizar, gera sentimentos de inferioridade, menos-valia, impotência e inadequação perante a sociedade, o que reforça o estigma da infertilidade. Tais resultados apontam a importância de reflexões sobre o papel da mulher na nossa cultura, visto que a maternidade é ainda utilizada como medida para o sucesso ou fracasso feminino. Faz-se necessário também refletir sobre a possibilidade da maior inserção do trabalho psicológico na reprodução assistida, visto a carga emocional e social envolvidas nesse processo.(AU)

This study aimed to analyze the conceptions of motherhood for infertile women from different socioeconomic levels who are undergoing assisted reproduction treatment. This is a qualitative and descriptive study that used a semi-structured interview as an instrument and included topics such as the meaning of family and desires/expectations about the child, pregnancy, and motherhood. A total of 48 infertile women over 35 years of ages using high-complexity assisted reproductive technologies in private and public institutions participated in this research. The data were treated by content analysis in which the following themes emerged: family social representations; social representations of motherhood; expectations with pregnancy and maternal models; and the imagined son. Participants represented the family in a positive way as a support system and the foundation and origin of love, embracing the family as a social bond. On the other hand, the family concepts based on inbreeding were also present, representing the family by perpetuation of the species and the importance of biological bonds. Motherhood was marked by significant idealization, being seen as a gratifying role and the fulfillment of femininity. The weight of the social demand to procreate was also felt as a duty to be fulfilled that, in the impossibility of carrying it out, generates feelings of inferiority, worthlessness, impotence, and inadequacy toward society, which reinforce the stigma of infertility. Results point to the necessary reflections on the role of women and our culture since Motherhood is still used as a measure of female success or failure. They also point to a reflection on the possibility of greater inclusion of psychological work in assisted reproduction given the emotional and social burden involved in this process.(AU)

Este estudio tuvo como objetivo analizar las concepciones de maternidad de mujeres infértiles, de diferentes niveles socioeconómicos, que se encuentran en tratamiento de reproducción asistida. Se trata de un estudio cualitativo, descriptivo, que utilizó como instrumento una entrevista semiestructurada e incluyó temas como el sentido de la familia, deseos/expectativas sobre el hijo y el embarazo y expectativas sobre la maternidad. Participaron en la investigación un total de 48 mujeres infértiles, mayores de 35 años, usuarias de tecnologías de reproducción asistida de alta complejidad en instituciones públicas y privadas. Los datos se sometieron a análisis de contenido del cual surgieron los temas: representaciones sociales familiares; representaciones sociales de la maternidad; expectativas con el embarazo y modelos maternos; hijo imaginado. Las participantes representaron a la familia de manera positiva, como sistema de apoyo, fundamento y origen del amor, configurándola como vínculo social. Por otro lado, también estuvieron presentes las concepciones familiares basadas en la consanguinidad, representando a la familia para la perpetuación de la especie y la importancia del vínculo biológico. La maternidad estuvo marcada por una importante idealización, vista como un rol gratificante y de realización de la feminidad. También se sintió el peso de la demanda social de procrear como un deber que cumplir y que, ante la imposibilidad de realizarlo, genera sentimientos de inferioridad, desvalorización, impotencia e inadecuación en la sociedad, lo que refuerza el estigma de la infertilidad. Por tanto, son necesarias reflexiones sobre el papel de la mujer en nuestra cultura, ya que la maternidad se sigue utilizando como medida del éxito o fracaso femenino. También se reflexiona sobre la posibilidad de una mayor inclusión del trabajo psicológico en la reproducción asistida dada la carga emocional y social que implica este proceso.(AU)

Sexes in sync: phenotypic plasticity, sexual selection and phenological synchrony between the sexes in a wild hibernator.

Desynchrony of phenological responses to climate change is a major concern for ecological communities. Potential uncoupling between one of the most fundamental divisions within populations, males and females, has not been well studied. To address this gap, we examined sex-specific plasticity in hibernation phenology in two populations of Columbian ground squirrels (Urocitellus columbianus). We find that both sexes display similar phenological plasticity to spring snowmelt dates in their timing of torpor termination and behavioural emergence from hibernation. As a result of this plasticity, the degree of protandry (i.e. males' emergences from hibernation preceding those of females) did not change significantly over the 27-year study. Earlier male behavioural emergence, relative to females, improved the likelihood of securing a breeding territory and increased annual reproductive success. Sexual selection favouring earlier male emergence from hibernation may maintain protandry in this population, but did not contribute to further advances in male phenology. Together, our results provide evidence that the sexes should remain synchronized, at least in response to the weather variation investigated here, and further support the role of sexual selection in the evolution of protandry in sexually reproducing organisms.

Sex-dependent phenological responses to climate vary across species' ranges.

Anthropogenic climate change has significantly altered the flowering times (i.e., phenology) of plants worldwide, affecting their reproduction, survival, and interactions. Recent studies utilizing herbarium specimens have uncovered significant intra- and inter-specific variation in flowering phenology and its response to changes in climate but have mostly been limited to animal-pollinated species. Thus, despite their economic and ecological importance, variation in phenological responses to climate remain largely unexplored among and within wind-pollinated dioecious species and across their sexes. Using both herbarium specimens and volunteer observations of cottonwood (Populus) species, we examined how phenological sensitivity to climate varies across species, their ranges, sexes, and phenophases. The timing of flowering varied significantly across and within species, as did their sensitivity to spring temperature. In particular, male flowering generally happened earlier in the season and was more sensitive to warming than female flowering. Further, the onset of flowering was more sensitive to changes in temperature than leaf out. Increased temporal gaps between male and female flowering time and between the first open flower date and leaf out date were predicted for the future under two climate change scenarios. These shifts will impact the efficacy of sexual reproduction and gene flow among species. Our study demonstrates significant inter- and intra-specific variation in phenology and its responses to environmental cues, across species' ranges, phenophases, and sex, in wind-pollinated species. These variations need to be considered to predict accurately the effects of climate change and assess their ecological and evolutionary consequences.

Construction and validation of the Sociosexual Skills Inventory / Construção e validação do Inventário de Habilidades Sociossexuais / Construcción y validación del Inventario de Habilidades Sociosexuales

The period of youth represents a milestone for sexual transitions, including casual practices. However, having erotic experiences does not presume competence in seeking casual sex (CS), and having a repertoire that is not socially competent for casual sex (CS) can lead to sexual risks. Accordingly, this study constructed and generated evidence of validity for a measure of social skills (SS) related to CS. Initially, 48 items were constructed and applied to a valid sample of 571 heterosexual, cisgender and single young people. Exploratory Factor Analysis was performed, the initial items were reduced to 18 and divided into two factors: Direct Sociosexual Skills, with 11 items (a = .81 and ω = .81), and Indirect Sociosexual Skills, with seven items (a = .67 and ω = .67). This instrument could contribute to the promotion of sexual health, as a more elaborate SS repertoire would be related to lower rates of abuse, sexually transmitted infections and harassment.(AU)

A juventude representa um marco para as transições sexuais, incluindo práticas casuais. Contudo, ter experiências eróticas não presume competência para sua busca, e um repertório pouco competente socialmente para o sexo casual (SC) pode levar a riscos sexuais. Nesse sentido, esse estudo construiu e gerou evidências de validade para uma medida de habilidades sociais (HS) relativas ao SC. Inicialmente, foram construídos 48 itens que foram aplicados a uma amostra válida de 571 jovens heterossexuais, cisgêneros e solteiros. Foi realizada a Análise Fatorial Exploratória, os itens foram reduzidos para 18 e divididos em dois fatores: Habilidades Sociossexuais Diretas, com 11 itens (α = 0,81 e ω = 0,81), e Habilidades Sociossexuais Indiretas, com sete itens (α= 0,67 e ω = 0,67). Este instrumento poderá contribuir para a promoção da saúde sexual, na medida que um repertório mais elaborado de HS estaria relacionado a menores índices de abuso, infecções sexualmente transmissíveis e assédio.(AU)

La juventud representa un hito para las transiciones sexuales, incluyendo prácticas casuales. Sin embargo, tener experiencias eróticas no supone competencia para buscarlas, y un repertorio socialmente inadecuado para el sexo casual (SC) puede conducir a riesgos sexuales. En este sentido, este estudio construyó y generó evidencias de validez para una medida de habilidades sociales (HS) relacionadas con el SC. Inicialmente, se crearon 48 ítems que se aplicaron a una muestra válida de 571 jóvenes heterosexuales, cisgénero y solteros. Se realizó un Análisis Factorial Exploratorio y los ítems se redujeron a 18 y se dividieron en dos factores: Habilidades Sociosexuales Directas, con 11 ítems (α= 0.81 y ω= 0.81), y Habilidades Sociosexuales Indirectas, con siete ítems (α= 0.67 y ω= 0,67). Este instrumento podría contribuir a la promoción de la salud sexual, ya que un repertorio de HS más elaborado se asocia con menores índices de abuso, infecciones de transmisión sexual y acoso sexual.(AU)

Genotypic sex shapes maternal care in the African pygmy mouse, Mus minutoides.

Sexually dimorphic behaviours, such as parental care, have long been thought to be mainly driven by gonadal hormones. In the past two decades, a few studies have challenged this view, highlighting the direct influence of the sex chromosome complement (XX versus XY or ZZ versus ZW). The African pygmy mouse, Mus minutoides, is a wild mouse species with naturally occurring XY sex reversal induced by a third, feminizing X* chromosome, leading to three female genotypes: XX, XX* and X*Y. Here, we show that sex reversal in X*Y females shapes a divergent maternal care strategy (maternal aggression, pup retrieval and nesting behaviours) from both XX and XX* females. Although neuroanatomical investigations were inconclusive, we show that the dopaminergic system in the anteroventral periventricular nucleus of the hypothalamus is worth investigating further as it may support differences in pup retrieval behaviour between females. Combining behaviours and neurobiology in a rodent subject to natural selection, we evaluate potential candidates for the neural basis of maternal behaviours and strengthen the underestimated role of the sex chromosomes in shaping sex differences in brain and behaviours. All things considered, we further highlight the emergence of a third sexual phenotype, challenging the binary view of phenotypic sexes.

Sex-Associated SNP Confirmation of Sex-Reversed Male Farmed Japanese Flounder Paralichthys olivaceus.

Female Japanese flounder Paralichthys olivaceus grow more rapidly than the male. The goal of all-female commercial production requires an efficient method of genetic sex identification. We conducted genome-wide association analysis of female and male farmed Japanese flounder (n = 24 per phenotypic sex) and found all regions of chromosome 24 to be significantly associated with phenotypic sex, suggesting it as the sex chromosome. Genetic sex was identified based on single nucleotide polymorphisms (SNP) on chromosome 24 (n = 3568) using multidimensional scaling analysis, and individuals were clearly separated according to sex by the first dimension. The 61 SNPs most highly associated with sex were selected, and an amplicon-based SNP panel was developed. This was used to determine genetic sex of 39 females and 40 males. Eleven phenotypic males were assigned as female with XX genotype, suggesting sex reversal. Genetic sex was also assessed based on the indel of the amh gene promoter, which is the major candidate sex gene of Japanese flounder. We found four SNPs perfectly associated with genotypic sex in the sex-associated SNP panel, one of which was located in exon 2 of the amh gene. Along with the indel of the amh gene promoter, the sex-associated SNP panel will be of value in identifying genetic sex of farmed Japanese flounder. Molecular sexing will facilitate all-female production by breeding sex-reversed males.