Gender and Sexuality in Greek Sport

Greek sport was in its earliest forms and predominantly thereafter a male activity. Greek masculine virtues were consistently reflected in texts discussing sport from Homer onward. The athletic and the martial spheres were often in tension regarding how greatly success in sport was valued as a measure of male excellence. The Greek gymnasium and athletic nudity were factors that fostered the Greek male sexual system of pederasty. Material culture in the form of sculpture, inscriptions, and vase paintings reflects the androcentrism of Greek sport. Female participation in Greek sport has a historical existence much less consistent and widespread than that of males, seen most prominently during the Roman empire.

Epigenetic mechanisms in sex determination and in the evolutionary transitions between sexual systems

The hypothesis that epigenetic mechanisms of gene expression regulation have two main roles in vertebrate sex is presented. First, and within a given generation, by contributing to the acquisition and maintenance of (i) the male or female function once during the lifetime in individuals of gonochoristic species; and (ii) the male and female function in the same individual, either at the same time in simultaneous hermaphrodites, or first as one sex and then as the other in sequential hermaphrodites. Second, if environmental conditions change, epigenetic mechanisms may have also a role across generations, by providing the necessary phenotypic plasticity to facilitate the transition: (i) from one sexual system to another, or (ii) from one sex-determining mechanism to another. Furthermore, if the environmental change lasts enough time, epimutations could facilitate assimilation into genetic changes that stabilize the new sexual system or sex-determining mechanism. Examples supporting these assertions are presented, caveats or difficulties and knowledge gaps identified, and possible ways to test this hypothesis suggested. This article is part of the theme issue ‘Challenging the paradigm in sex chromosome evolution: empirical and theoretical insights with a focus on vertebrates (Part I)’.

Physiological Features of the Reproductive System of Female Nutria

This article provides information about a promising alternative field of animal husbandry – nutria breeding. This involves the production of fur and high-quality meat products, which contain a large amount of nitrogenous extractives and muscle hemoglobin. This study examined the sexual system of female nutria, and the dynamics, duration and features of each stage of the female nutria’s sexual cycle, including estrus, sexual arousal, hunting, braking and phase balancing. The methods of observation, clinical examination, research of smears and fingerprints, and analysis of the cytogram of the vaginal epithelium at different stages of sexual and physiological maturity of female nutria were used. When analyzing the cytogram of the vaginal epithelium, the structure, color, and percentage of basal, parabasal, superficial, and keratinized cells were indicated. Information about the timing of sexual and physiological maturity, their features, processes and signs of manifestation, and different timing of sexual and physiological maturity in summer and winter is provided. Keywords: nutria, female, puberty, physiological maturity

A leaky dimorphic sexual system and breeding system characterize a successful island colonist: the reproductive biology of Plocama pendula (Rubiaceae)

Island plants provide special opportunities for the study of evolution and ecology. In field and greenhouse studies we characterized a model reproductive system for Plocama pendula, endemic to the Canary Islands. This species has a complicated and not immediately obvious reproductive system. Pollination is biotic, and all flowers are morphologically hermaphroditic, but half of the plants characteristically bear flowers with nectar, pistils with reflexed stigmatic lobes and pollen-less anthers (i.e. they are functionally female flowers). The other half bear nectar-less flowers with abundant pollen and full-sized pistils that mostly have un-reflexed stigmatic lobes (i.e. they are hermaphroditic flowers functioning mostly as males). However, experiments show these pollen-bearing flowers to be self-compatible. Thus, the functionally male flowers have a breeding system that allows selfing in limited circumstances, but the functionally male flowers produce far fewer fruits than do functionally female flowers. With morphologically gynodioecious, functionally largely dioecious flowers, sometimes capable of selfing, the reproductive system of this species could be labelled as ‘leaky’ in many respects. Thus, we propose that P. pendula has colonized new habitats and persists in substantial populations at least in part because it manifests a reproductive system that is a model for successfully balancing the often-conflicting evolutionary demands of colonization, establishment and persistence.

Phenotypic Variation in an Asexual-Sexual Fish System: Visual Lateralization

Sexual reproduction is nearly ubiquitous in the vertebrate world, yet its evolution and maintenance remain a conundrum due to the cost of males. Conversely, asexually reproducing species should enjoy a twofold population increase and thus replace sexual species all else being equal, but the prevalence of asexual species is rare. However, stable coexistence between asexuals and sexuals does occur and can shed light on the mechanisms asexuals may use in order to persist in this sex-dominated world. The asexual Amazon molly (Poecilia formosa) is required to live in sympatry with one of its sexual sperm hosts –sailfin molly (Poecilia latipinna) and Atlantic molly (Poecilia mexicana)—and are ecological equivalents to their host species in nearly every way except for reproductive method. Here, we compare the visual lateralization between Amazon mollies and sailfin mollies from San Marcos, Texas. Neither Amazon mollies nor sailfin mollies exhibited a significant eye bias. Additionally, Amazon mollies exhibited similar levels of variation in visual lateralization compared to the sailfin molly. Further investigation into the source of this variation –clonal lineages or plasticity—is needed to better understand the coexistence of this asexual-sexual system.

An Overview of Sexual Systems

The Crustacea have evolved a broad range of sexual systems, including various types of gonochorism, hermaphroditism, and parthenogenesis. This chapter provides an overview of sexual systems in Crustacea and compares them in the species-rich Decapoda, Isopoda, Amphipoda, Cirripedia, Cladocera, Copepoda, and Ostracoda, which differ considerably with respect to phylogeny, ecology, and life histories. Gonochorism is considered to be the ancient sexual system of Crustacea. Hermaphroditism and parthenogenesis originated many times independently from gonochorism and occur in an estimated 2.2% and 2.4% of species, respectively. Crustaceans differ from the other arthropod groups mainly by the abundance and diversity of hermaphroditic reproduction. Phylogenetic analysis of extant species, the fossil record, and evolutionary ecological theory enable the reconstruction and explanation of divergent evolutionary trajectories of sexuality in the crustacean groups. The specificities can partly be attributed to differences in lifestyle, life history, and adaptive responses to different environments, but may also be the result of evolutionary constraint and competing adaptive strategies that lower the propensity of sexual system shifts. The genetic underpinning and molecular mediation of sexual system shifts are beginning to be unraveled in entomostracan and malacostracan models. A better understanding of the sexual systems in Crustacea may help to optimize their culture and conservation and answer key evolutionary questions like the enigma of sex.

Seeing what you want to see: Sexual activation makes potential partners seem more appealing and romantically interested

Recent studies have indicated that activation of the sexual system fosters relationship initiation. In three studies, we expand on this work to investigate whether sexual activation encourages initiating relationship with prospective partners by biasing the way they are perceived. In all studies, participants encountered a potential partner and rated this partner’s attractiveness and romantic interest following sexual activation. Participants’ interest in the partner was self-reported or evaluated by raters. Study 1 revealed that sexual activation led participants to perceive potential partners as more attractive and interested in oneself. Study 2 added to these findings, providing a test of sexual priming rather than more general closeness priming. Mediational analyses in Study 3 indicated that heightened romantic interest mediated the link between sexual activation and perceiving potential partners as more interested in oneself. These findings suggest that sexual activation facilitates relationship initiation by motivating projection of one’s desires onto prospective partners.