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Ecological character displacement between the sexes, and sexual selection, integrate into a convergent set of factors that produce sexual variation. Ecologically modulated, sexually mediated variation within and between sexes may be a major contributor to the amount of total variation that selection can act on in species. Threespine stickleback (Gasterosteus aculeatus) display rapid adaptive responses and sexual variation in many phenotypic traits. We examined phenotypic variation in the skull, pectoral and pelvic girdles of threespine stickleback from two freshwater and two coastal marine sites on the Sunshine Coast of British Columbia, Canada, using an approach that avoids a priori assumptions about bimodal patterns of variation. We quantified shape and size of the cranial, pectoral and pelvic regions of sticklebacks in marine and freshwater habitats using 3D geometric morphometrics and an index of sexually mediated variation. We show that the expression of phenotypic variation is structured in part by the effects of both habitat marine vs freshwater and the effects of individual sites within each habitat. Relative size exerts variable influence, and patterns of phenotypic variation associated with sex vary among body regions. This fine-grained quantification of sexually mediated variation in the context of habitat difference and different anatomical structures indicates a complex relationship between genetically inferred sex and environmental factors, demonstrating that the interplay between shared genetic background and sexually mediated, ecologically based selective pressures structures the phenotypic expression of complex traits.
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Considerable heterogeneity and ontogenetic changes in venom composition have already been observed in different species of snakes within the Viperidae family. Since the venom of young and adult can cause distinct pathological effects and because the antivenom may be less effective in neutralizing envenoming by young snakes compared to adults, it is of paramount importance to understand the ontogenetic variation of snake venom. Thus, the present study aimed to analyze and compare the venom of Bothrops pauloensis snakes, searching for possible influences of ontogeny and sex in their biochemical and biological aspects. The venom of younger individuals was more complex in relation to high molecular mass proteins, with a greater abundance of metalloproteinases, while adults showed a greater abundance of medium and low molecular mass proteins, such as phospholipases A2 (PLA2), C-type lectins and serine proteases. The antivenom showed better immunorecognition towards the venom of adult snakes than younger ones, in addition to a deficiency in the recognition of medium molecular mass proteins, suggesting the need for an improvement in the antivenom. Younger snakes showed higher coagulant, caseinolytic, and hemorrhagic activity, while adult snakes showed higher L-amino acid oxidase (LAAO) activity and acted faster in lethality. Differences between males and females were observed mainly in the rate of loss of coagulant activity, change in PLA2 activity and lethality action time. Furthermore, considering only the adult groups, males showed a higher LAAO and thrombin-like activity, while females showed a higher caseinolytic and hyaluronidase activity. With the results obtained in this work, it was possible to conclude that there is an ontogenetic variation in the composition and some activities of the B. pauloensis snake venom, in addition to differences between the venom of males and females, reinforcing that there is an intraspecific variation that may result in different symptoms in their envenoming and, consequently, differences in the response to treatment with the antivenom.
Assuntos
Bothrops , Venenos de Crotalídeos , Animais , Antivenenos , Bothrops/metabolismo , Venenos de Crotalídeos/química , Venenos de Crotalídeos/toxicidade , Feminino , Masculino , Metaloproteases/metabolismo , Fosfolipases A2/metabolismo , Proteínas , Venenos de Serpentes/química , SerpentesRESUMO
Considerable heterogeneity and ontogenetic changes in venom composition have already been observed in different species of snakes within the Viperidae family. Since the venom of young and adult can cause distinct pathological effects and because the antivenom may be less effective in neutralizing envenoming by young snakes compared to adults, it is of paramount importance to understand the ontogenetic variation of snake venom. Thus, the present study aimed to analyze and compare the venom of Bothrops pauloensis snakes, searching for possible influences of ontogeny and sex in their biochemical and biological aspects. The venom of younger individuals was more complex in relation to high molecular mass proteins, with a greater abundance of metalloproteinases, while adults showed a greater abundance of medium and low molecular mass proteins, such as phospholipases A2 (PLA2), C-type lectins and serine proteases. The antivenom showed better immunorecognition towards the venom of adult snakes than younger ones, in addition to a deficiency in the recognition of medium molecular mass proteins, suggesting the need for an improvement in the antivenom. Younger snakes showed higher coagulant, caseinolytic, and hemorrhagic activity, while adult snakes showed higher L-amino acid oxidase (LAAO) activity and acted faster in lethality. Differences between males and females were observed mainly in the rate of loss of coagulant activity, change in PLA2 activity and lethality action time. Furthermore, considering only the adult groups, males showed a higher LAAO and thrombin-like activity, while females showed a higher caseinolytic and hyaluronidase activity. With the results obtained in this work, it was possible to conclude that there is an ontogenetic variation in the composition and some activities of the B. pauloensis snake venom, in addition to differences between the venom of males and females, reinforcing that there is an intraspecific variation that may result in different symptoms in their envenoming and, consequently, differences in the response to treatment with the antivenom.
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The intra-specific variation of two species of Helorus Latreille (Hymenoptera, Heloridae) from NW China is studied and for the first time the sexual variation in Chinese Helorus species is described. Both sexes of Helorus antefurcalis He Xu, 2015 (new for Shaanxi) and H. caii He Xu, 2015 (up to now only known from one male), are described and illustrated. Helorus xinjiangensis He Xu, [June] 2015, is a new junior synonym of H. alborzicus Izadizadeh, van Achterberg Talebi, [April] 2015 and H. elgoni Risbec, 1950, is re-instated as valid species. A revised key to the Old World species of Helorus Latreille (except Australian region) is included.
Assuntos
Himenópteros , Animais , China , Feminino , MasculinoRESUMO
Snakes are complex mixtures whose main functions are the stoppage and the killing of prey as well as the initial promotion of digestion and their actions may vary according to the age, geographical distribution and individual character of each snake. The venom of Bothrops alternatus, as well as most of the botrópico venoms, has as main actions, proteolytic, coagulant and hemorrhagic activities. The objective of this study was to evaluate the possible variations of venoms of male and female snakes of the Bothrops alternatus species throughout the development, through biochemical characterization (protein dosage, SDS-PAGE electrophoresis, gelatinolytic activity, caseinolytic activity and coagulant activity) and biological characterization (hemorrhagic and myotoxic activity). As a result, protein content of male and female venoms did not show ontogenetic or sexual variation, with 90 to 100% protein content. The electrophoretic profiles of the venoms were similar, but a protein with an approximate molecular weight of 17.0 kDa varied between the sexes and as the snakes developed. By means of the SDS-PAGE zimography and caseinolytic activity, it was possible to observe that the proteolytic action of the female venoms was not very active, with action only in the third and fourth year, whereas the male venoms showed activity only in the first year of life. The B. alternatus venoms had the ability to coagulate citrated equine plasma in 60 seconds and venoms of both sexes were more coagulant in the first year of life, suffering a decline in action throughout development. In the hemorrhagic activity the venom samples presented sexual variation, and the ontogenetic variation was only observed in the venoms of males, where they were more active in the fourth year of age. The myotoxic activity of B. alternatus venoms showed that there is sexual variation, whereas ontogenetic variation was only identified in the venom of males, with oscillations of the specific activity values for the CK enzyme. By means of the joint analysis of the data generated, we conclude that there is sexual and ontogenetic variation in venoms of the species B. alternatus and that several factors can influence in the triggering of their actions and activities, since environmental and genetic factors are the key to the maintenance species in the habitat in which they live.
Os venenos ofídicos são misturas complexas e tem como funções principais a paralisação e o abate da presa, bem como a promoção inicial da digestão e suas ações podem variar de acordo com a idade, a distribuição geográfica e o caráter individual de cada serpente. O veneno de Bothrops alternatus, assim como a maioria dos venenos botrópicos, tem como principais ações, as atividades proteolítica, coagulante e hemorrágica. O objetivo desse estudo foi avaliar as possíveis variações dos venenos de serpentes machos e fêmeas da espécie Bothrops alternatus ao longo do desenvolvimento, através de caracterização bioquímica (dosagem de proteínas, eletroforese em SDS-PAGE, atividade gelatinolítica, atividade caseinolítica e atividade coagulante) e caracterização biológica (atividade hemorrágica e miotóxica). Como resulados, teor proteico dos venenos de machos e fêmeas não apresentou variação ontogenética ou sexual, com teor entre 90 e 100% de proteína. Os perfis eletroforéticos dos venenos foram semelhantes, porém uma proteína com peso molecular aproximado de 17.0 kDa variou entre os sexos e conforme o desenvolvimento das serpentes. Por meio das técnicas de zimografia em SDS-PAGE e atividade caseinolítica foi possível observar que a ação proteolítica dos venenos de fêmeas apresentou-se pouco ativo, com ação somente no terceiro e quarto ano, enquanto que os venenos de machos mostraram atividade somente no primeiro ano de vida. Os venenos de B. alternatus tiveram a capacidade de coagular o plasma equino citratado em 60 segundos e os venenos de ambos os sexos foram mais coagulantes no primeiro ano de vida, sofrendo um declínio na ação ao longo do desenvolvimento. Na atividade hemorrágica as amostras de venenos apresentaram variação sexual, sendo a variação ontogenética só observada nos venenos de machos, onde foram mais ativos no quarto ano de idade. A atividade miotóxica dos venenos de B. alternatus mostrou que existe variação sexual, enquanto que a variação ontogenética só foi identificada nos venenos de machos, apresentando oscilações dos valores da atividade específica para a enzima CK. Por meio da análise conjunta dos dados gerados, concluímos que existe variação sexual e ontogenética em venenos da espécie B. alternatus e que diversos fatores podem influenciar no desencadear de suas ações e atividades, visto que, fatores ambientais e genéticos são a chave para a manutenção das espécies no habitat em que vivem.
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BACKGROUND: Cultures play a significant role not only in the causation and management of emotional distress and psychiatric disorders but also in sexual variation and attitudes towards sexual minority groups. AIM: To discuss the potential impact of culture on sexual minorities. METHOD: This lecture reviews the relation between sexuality, culture and mental health. RESULTS: Cultures define what is deviant and unacceptable or even illegal. Attitudes to sex, perceived role of and actual sexual activity are very strongly influenced by cultural values. Cultures may see sexual activity as largely procreative (sex-negative) or as a pleasurable (sex-positive) activity. Furthermore, gender roles and gender role expectations influence relationships between different-sex partners. Although epidemiological data on prevalence of sexual minorities across cultures are scanty, it may reflect underlying attitudes to minority groups. CONCLUSIONS: It is crucial that clinicians are aware of the role that culture plays in acceptance or rejection of sexual minorities.
Assuntos
Atitude , Cultura , Saúde Mental , Comportamento Sexual/etnologia , Minorias Sexuais e de Gênero/psicologia , Humanos , Comportamento Sexual/psicologiaRESUMO
Avoiding foraging under increased predation risk is a common anti-predator behaviour. Using artificial light to amplify predation risk at ecologically valuable sites has been proposed to deter introduced mice (Mus musculus) and ship rats (Rattus rattus) from degrading biodiversity in island ecosystems. However, light may adversely affect native species; in particular, little is known about invertebrate responses to altered lighting regimes. We investigated how endemic orthopterans responded to artificial light at Maungatautari Ecological Island (Waikato, New Zealand). We predicted that based on their nocturnal behaviour, ecology and evolutionary history, tree weta (Hemideina thoracica) and cave weta (Rhaphidophoridae) would reduce their activity under illumination. Experimental stations (nâ¯=â¯15) experienced three evenings under each treatment (order randomised): (a) light (illuminated LED fixture), (b) dark (unilluminated LED fixture) and (c) baseline (no lighting fixture). Weta visitation rates were analysed from images captured on infra-red trail cameras set up at each station. Light significantly reduced the number of observations of cave (71.7% reduction) and tree weta (87.5% reduction). In observations where sex was distinguishable (53% of all visits), male tree weta were observed significantly more often (85% of visits) than females (15% of visits) and while males avoided illuminated sites, no detectable difference was observed across treatments for females. Sex could not be distinguished for cave weta. Our findings have implications for the use of light as a novel pest management strategy, and for the conservation of invertebrate diversity and abundance within natural and urban ecosystems worldwide that may be affected by light pollution.
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Aprendizagem da Esquiva/efeitos da radiação , Ortópteros/fisiologia , Animais , Biodiversidade , Ecologia , Ecossistema , Feminino , Luz , Masculino , Nova Zelândia , Ortópteros/efeitos da radiação , Fótons , Comportamento Predatório/efeitos da radiaçãoRESUMO
In response to seasonal variation in energy availability and thermal environment, physiological and endocrine mechanisms have evolved in temperate zone animals. Seasonal changes in hormone activity affect metabolism, body temperature, and reproductive activity. We examined the seasonal regulatory role of hormones on basal metabolic rate (BMR) and regulatory nonshivering thermogenesis (RNST) in 98 female and 17 male adult Eptesicus fuscus (big brown bat). We measured BMR, RNST, and plasma levels of thyroid hormone (T3), leptin, and cortisol in bats captured in maternity colonies in eastern Massachusetts from May to August (from arousal from the hibernation phase to the prehibernation phase). We hypothesized that all three hormones are seasonally primarily metabolic hormones and secondarily thermogenic hormones. In males, only BMR significantly changed seasonally. In females, all five variables significantly changed seasonally. The seasonal pattern of plasma leptin and cortisol levels correlated with the seasonal pattern of BMR, with an initial increase followed by a decrease, suggesting that leptin and cortisol are primarily metabolic hormones. The seasonal pattern of plasma T3 levels generally paralleled the basic seasonal pattern of RNST, with both increasing at the second half of the season, suggesting that T3 is primarily a thermogenic hormone. The observed decrease in plasma leptin levels may be necessary to allow for the observed seasonal decrease in BMR, with the similar cortisol pattern important for leptin regulation. While T3 is needed to maintain BMR, it may play a more critical role in the seasonal regulation of RNST than of BMR.
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Regulação da Temperatura Corporal/fisiologia , Quirópteros/fisiologia , Metabolismo Energético/fisiologia , Hidrocortisona/sangue , Leptina/sangue , Animais , Quirópteros/sangue , Feminino , Masculino , Estações do Ano , Fatores Sexuais , Tiroxina/sangueRESUMO
The Mexican Garter Snake (Thamnophis eques) is a terrestrial-aquatic generalist that feeds on both aquatic and terrestrial prey. We describe size-related variation and sexual variation in the diet of T. eques through analysis of 262 samples of identifiable stomach contents in snakes from 23 locations on the Mexican Plateau. The snake T. eques we studied consumed mostly fish, followed in lesser amounts by leeches, earthworms, frogs, and tadpoles. Correspondence analysis suggested that the frequency of consumption of various prey items differed between the categories of age but not between sex of snakes, and the general pattern was a reduction of prey item diversity with size of snake. Snake length was correlated positively with mass of ingested prey. Large snakes consumed large prey and continued to consume smaller prey. In general, no differences were found between the prey taxa of male and female snakes, although males ate two times more tadpoles than females. Males and females did not differ in the mass of leeches, earthworms, fishes, frogs and tadpoles that they ate, and males and females that ate each prey taxon were similar in length. We discuss proximate and functional determinants of diet and suggest that the observed intraspecific variation in T. eques could be explored by temporal variation in prey availability, proportions of snake size classes and possible sexual dimorphism in head traits and prey dimensions to assess the role of intersexual resource competition.
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Results from this study of the white shark Carcharodon carcharias include measurements obtained using a novel photographic method that reveal significant differences between the sexes in the relationship between tooth cuspidity and shark total length, and a novel ontogenetic change in male tooth shape. Males exhibit broader upper first teeth and increased distal inclination of upper third teeth with increasing length, while females do not present a consistent morphological change. Substantial individual variation, with implications for pace of life syndrome, was present in males and tooth polymorphism was suggested in females. Sexual differences and individual variation may play major roles in ontogenetic changes in tooth morphology in C. carcharias, with potential implications for their foraging biology. Such individual and sexual differences should be included in studies of ontogenetic shift dynamics in other species and systems.
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Tubarões/anatomia & histologia , Dente/anatomia & histologia , Animais , Feminino , Masculino , Caracteres Sexuais , Tubarões/crescimento & desenvolvimentoRESUMO
Gut microbiota are widely involved in insect biology, and many factors can influence the microbiota in guts and frass. Dendroctonus valens is a very destructive forest pest in China, and the mass-attacking behavior is regulated by several semiochemicals, including verbenone, a multifunctional pheromone. The beetle harbors a variety of bacteria in its guts and frass and some of them are capable of verbenone production. D. valens is characterized by monogamy and female-initiated attacking behavior. Whether the bacterial communities fluctuate according to sex, and whether the variation influences the verbenone production, remains to be determined. In this study, the bacterial microbiota in D. valens guts and frass were analyzed, and verbenone production by their crude bacterial suspensions was compared in vitro. Bacterial diversity in female frass is more abundant compared to male frass, and the percentages and total amounts of main genera like Lactococcus and Pseudomonas in female frass are significantly higher than those in male frass. The verbenone produced by the female frass suspension is significantly higher than male frass. This study presents a comprehensive comparison of bacterial communities in guts and frass between both sexes of D. valens, highlighting the potential significance of female frass microbiota in verbenone production.
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Feromônios/metabolismo , Terpenos/metabolismo , Gorgulhos/metabolismo , Gorgulhos/microbiologia , Animais , Monoterpenos Bicíclicos , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal , Masculino , Fatores SexuaisRESUMO
Human sexuality plays a major role in an individual's existence and functioning. In addition, rightly or wrongly sexuality often defines people and also affects social attitudes. These attitudes, if negative, can contribute to stigma and prevent people from help seeking if they are suffering from mental health problems. Recent changes in policy towards same-sex relationships have been positive in many countries including the UK and the USA, whereas in others such as Russia and Uganda attitudes have become more negative and punitive. Sexual activity is seen as having both pleasurable and procreational functions which contribute to society's attitudes to homosexual behaviour. Inevitably, individual responses to their own sexuality and sexual behaviour will be influenced by social attitudes. To ensure that those with various sexual variations can access psychiatric services without discrimination, various levels of interventions are needed. Here we discuss different levels of intervention and organizational change that may make it possible. Social organization and institutional organization of services need to be sensitive, especially as rates of many mental disorders are high in individuals who may be sexually variant. Those providing services need to understand their own negative attitudes as well as prejudices to ensure that services are emotionally accessible.
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Serviços de Saúde/normas , Saúde Mental/normas , Preconceito , Sexualidade , HumanosRESUMO
Sexual variation has been reported across cultures for millennia. Sexual variation deals with those facets of sexual behavior which are not necessarily pathological. It is any given culture that defines what is abnormal and what is deviant. In scriptures, literature and poetry in India same sex love has been described and explained in a number of ways. In this paper we highlight homosexual behavior and the role of hijras in the Indian society, among other variations. These are not mental illnesses and these individuals are not mentally ill. Hence the role of psychiatry and psychiatrists has to be re-evaluated. Attitudes of the society and the individual clinicians may stigmatize these individuals and their behavior patterns. Indian psychiatry in recent times has made some progress in this field in challenging attitudes, but more needs to be done in the 21(st) century. We review the evidence and the existing literature.