The Tardigrada are hydrophilous, segmented, molting micrometazoans that occupy a diversity of niches in freshwater, marine, and terrestrial habitats. A sister group of the arthropods, this phylum of bilaterally symmetrical lobopods, most less than 1 mm in length, have a hemocoel, a complete digestive tract, a dorsal gonad with one or two gonoducts, and a dorsal lobed brain with a ventral nerve cord and five ganglia. About 1000 species have been described based on the morphology of sclerified structures, especially the claws and buccal-pharyngeal apparatus. Reproduction occurs through fertilized or unfertilized eggs, with individuals being either gonochoric, unisexual, or hermaphroditic, and eggs are deposited either freely or within the shed exuvium. Parthenogenesis, very frequent in limnic and terrestrial tardigrades, allows them to colonize new territories by passive dispersal of a single individual. Quiescence (cryptobiosis: anhydrobiosis, anoxybiosis, cryobiosis, and osmobiosis) and diapause (encystment and resting eggs) occur during the tardigrade life history. Ecological parameters and global distribution patterns are poorly known or understood. Methods for collection, microscopy, and culturing have been developed.

Introdução: O hermafroditismo verdadeiro, caracterizado pela demonstração histológica de tecido ovariano e testicular no mesmo indivíduo, responde por cerca de 5% dos casos de anomalia da diferenciação sexual. Como a variabilidade fenotípica é muito grande, desde mulheres com genitália externa normal até homens com genitália externa normal, passando por toda uma gama de apresentações intermediárias, torna-se impossível o diagnóstico baseado apenas em dados clínicos. A avaliação da presença de tecido testicular é bem estabelecida, mas não há teste para a demontração de tecido ovariano. A inibina A é produzida exclusivamente no ovário e é estimulada pelas gonadotrofinas. Objetivos: 1. Avaliar a efetividade do método de estimulação gonadal com a associação LH/FSH na demonstração de tecido ovariano; 2. Avaliar a eventual presença de tecido ovariano em pacientes com anomalias da diferenciação sexual através da dosagem sérica de Inibina A e de estradiol após estímulo gonadotrófico e; 3. Facilitar o diagnóstico de hermafroditismo verdadeiro antes da fase de exploração cirúrgica das gônadas. Métodos: Foram incluídos no estudo, dez pacientes com hiperplasia congênita de supra-renal, dez pacientes com criptorquidia unilateral isolada, treze pacientes com anomalia da diferenciação sexual sem etiologia definida e sete pacientes com hermafroditismo verdadeiro com diagnóstico histológico. Todos os pacientes foram submetidos a um teste de estímulo gonadotrófico, representado pela administração de gonadotrofina humana da menopausa (menotropina), que tem em sua composição LH e FSH, na dose de 150 UI de cada gonadotrofina, por via intramuscular, durante três dias subseqüentes. Dosagens de LH, FSH, estradiol, testosterora e inibina A foram realizadas antes (B), 24h após a primeira dose (A1) e 24 horas após a terceira dose (A2). Resultados: O LH não apresentou elevação significativa nos quatro grupos. O FSH elevou-se nos quatro grupos de forma progressiva e semelhante. O estradiol elevou-se significativamente nos grupos de pacientes com hiperplasia congênita das supra-renais (p=0,005) e de pacientes com hermafroditismo verdadeiro (p=0,031), enquanto a testosterona elevou-se nos grupos com criptorquidia isolada (p=0,027) e de pacientes com ambigüidade genital sem etiologia definida (p=0,028). A inibina A elevou-se significativamente nos grupos de pacientes com hiperplasia congênita das supra-renais (p=0,005) e com hermafroditismo verdadeiro (p=0,043). Conclusão: O teste de estímulo com LH e FSH mostrou-se útil para o diagnóstico da presença de tecido ovariano tanto em pacientes com hiperplasia congênita das supra-renais, como naqueles com hermafroditismo verdadeiro. / Introduction: True hermaphrodism (TH) is characterized by the presence of ovarian and testicular tissue in the same patient comprises 5% of the intersex cases. A large spectrum of phenotypical variation is observed, ranging from normal female genitalia to normal male genitalia, covering a wide range of intermediary presentations, it becomes very difficult to make the diagnosis of TH on clinical basis. The detection of testicular tissue is well stablished but there is no available test to demonstrate the presence of ovarian tissue. Objectives: 1. To evaluate the effectiveness of the LH/FSH gonadal stimulation in demonstrating ovarian functiom 2. To evaluate the presence of ovarian tissue in intersex patients under gonadotropic stimulation and 3. To make the TH diagnosis before the surgical procedure. Patients and Methods: Ten patients with congenital adrenal hyperplasia (CAH), 10 with unilateral cryptorchidism, 13 intersex patients with no defined etiology, and seven TH patients have been included in the study. All the patients had a gonadotropic stimulation test with human menopausal gonadotropin (menotropin-hMG),150 IU, intramuscular, for three consecutive days. LH, FSH, estradiol, testosterone, and Inhibin A were measured before (0 time), 24h after the first gonadotropin dose, and 24h after the third gonadotropin dose. Results: LH did not show any significant increase in the four groups studied. FSH increased in the four groups in a similar way. Estradiol increased in CAH pacients (p=0.005) and in TH patients (p=0,031), while testosterone increased in patients whit unilateral cryptorchidism (p=0.027) as well as in the intersex patients without defined etiology. Inhibin A levels increased in CAH patients (p=0.005) and in the TH patients (p=0.043). Conclusion: The LH/FSH stimulation test demonstrated to be a useful method to diagnose the presence of ovarian tissue in CAH patients as well as in TH patients, becoming an important tool to diagnose TH even before the surgical procedure and histologic studies of the gonads.

Objetivo: Avaliar os resultados da genitoplastia masculinizante, com a técnica de Denis Browne, realizada em um grande grupo de pacientes com distúrbios do desenvolvimento sexual (DDS) tratados em um único hospital de referência. Pacientes e Métodos: Avaliamos 65 pacientes (57 com DDS 46,XY e 8 com DDS 46,XX) com hipospádia proximal e genitália ambígua. Os resultados cosméticos e sintomas urinários foram avaliados objetivamente e os pacientes responderam a um questionário sobre sintomas urinários, atividade sexual e satisfação pessoal após o tratamento cirúrgico. A idade dos pacientes na primeira cirurgia foi em média de 9 ± 10 anos e o segundo tempo cirúrgico foi realizado em média 14,5 ± 16,3 meses após a primeira cirurgia. O seguimento destes pacientes foi em média de 15,1 ± 10 anos e a idade dos pacientes na avaliação final foi em média de 25,9 ± 14,1 anos. Resultados: O aspecto cosmético foi considerado bom em 44%, regular em 53% e ruim em 3% dos pacientes. Houve diferença estatisticamente significante na média do tamanho peniano antes do tratamento entre os grupos com deficiência de 5-RD2 e com DDS de etiologia indeterminada (p<0,05). A média do tamanho peniano na avaliação final dos pacientes póspúberes foi de 7,8 ±2,4 cm, variando de 4 to 12 cm correspondendo a -4,4 ± 1,3 DP (-6,5 a -1,5 DP). Houve diferença estatisticamente significante no tamanho peniano entre os grupos com deficiência na produção de testosterona e com deficiência de 5-RD2 e entre os grupos com DDS de etiologia indeterminada e deficiência de 5-RD2 (p<0,05). O grupo com deficiência de 5-RD2 apresentou o menor tamanho peniano na avaliação final (-5,4±1 DP). As complicações mais freqüentes foram a fistula uretral encontradas em 50% dos pacientes seguida de estenose, presente em 20% dos pacientes. O sintoma urinário mais freqüente foi a perda urinária pós miccional. A atividade sexual foi referida por 86% dos pacientes adultos sendo definida como adequada em 60%, satisfatória em 29% e insatisfatória em 11% dos pacientes. Em relação ao resultado cirúrgico, 84% dos pacientes referiram estar satisfeitos porem 11% estavam insatisfeitos com o tamanho peniano e 5% com a presença de estenose uretral. Conclusão: A maioria dos pacientes com DDS submetidos a genitoplastia masculinizante pela técnica de Denis Browne mostrou-se satisfeita com os resultados cirúrgicos. Entretanto, queixas sobre o tamanho peniano, atividade sexual e micção indicam que novas abordagens devem ser desenvolvidas para melhor resultado morfológico e funcional dos pacientes com distúrbio do desenvolvimento sexual. / Purpose: To evaluate the results of masculinizing genitoplasty with the Denis Browne technique performed in a large cohort of patients with disorders of sex development (DSD) treated at a single tertiary centre. Patients and Methods: We evaluated 65 patients (57 with 46,XY DSD and 8 with 46,XX DSD) with proximal hypospadias and genital ambiguity. Cosmetic results and the urinary stream were evaluated objectively, and the patients responded questionnaires regarding satisfaction with the surgical results, as well as urinary and sexual symptoms. The age at first surgery was 9±10 years and the second stage was performed after 14.5±16.3 months. The mean followup was 15.1±10 years and the average patients age at the last examination was 25.9±14.1 years. Results: Cosmetic results were considered good in 44%, regular in 53% and poor in 3% of the cases. The comparison of the mean penile length among 46,XY DSD groups identified a significant statistically difference between 5-RD2 deficiency and undetermined DSD groups at diagnosis (p<0.05). The mean penile length at last clinical evaluation in post-pubertal patients was 7.8 ±2.4 cm, ranging from 4 to 12 cm corresponding to -4,4 ± 1,3 SD (-6.5 to -1.5 SD) and there was a significant statistically difference in the mean penile length amongst testosterone production deficiency and undetermined DSD groups with 5-RD2 deficiency group (p<0.05). The 5RD2 deficiency group presented the smallest penile length at the last evaluation (-5.4±1 SD). The most common complications were urethral fistula (50%) and stenosis (20%) and the most frequent urinary symptom was dribbling after micturition. Sexual activity was reported by 86% of adult patients and was adequate in 60%, satisfactory in 29% and unsatisfactory in 11% of them. Overall, 84% referred satisfaction with surgical results, but 11% complained about penile length and 5% about urethral stenosis. Conclusion: Most of the DSD patients were satisfied with the longterm results of masculinizing genitoplasty using Denis Browne technique, although specific complaints about small penis size, sexual activity and urinary symptoms were frequent. New approaches should be developed to achieve full satisfaction of DSD patients in adulthood.

Introdução: O hermafroditismo verdadeiro, caracterizado pela demonstração histológica de tecido ovariano e testicular no mesmo indivíduo, responde por cerca de 5% dos casos de anomalia da diferenciação sexual. Como a variabilidade fenotípica é muito grande, desde mulheres com genitália externa normal até homens com genitália externa normal, passando por toda uma gama de apresentações intermediárias, torna-se impossível o diagnóstico baseado apenas em dados clínicos. A avaliação da presença de tecido testicular é bem estabelecida, mas não há teste para a demontração de tecido ovariano. A inibina A é produzida exclusivamente no ovário e é estimulada pelas gonadotrofinas. Objetivos: 1. Avaliar a efetividade do método de estimulação gonadal com a associação LH/FSH na demonstração de tecido ovariano; 2. Avaliar a eventual presença de tecido ovariano em pacientes com anomalias da diferenciação sexual através da dosagem sérica de Inibina A e de estradiol após estímulo gonadotrófico e; 3. Facilitar o diagnóstico de hermafroditismo verdadeiro antes da fase de exploração cirúrgica das gônadas. Métodos: Foram incluídos no estudo, dez pacientes com hiperplasia congênita de supra-renal, dez pacientes com criptorquidia unilateral isolada, treze pacientes com anomalia da diferenciação sexual sem etiologia definida e sete pacientes com hermafroditismo verdadeiro com diagnóstico histológico. Todos os pacientes foram submetidos a um teste de estímulo gonadotrófico, representado pela administração de gonadotrofina humana da menopausa (menotropina), que tem em sua composição LH e FSH, na dose de 150 UI de cada gonadotrofina, por via intramuscular, durante três dias subseqüentes. Dosagens de LH, FSH, estradiol, testosterora e inibina A foram realizadas antes (B), 24h após a primeira dose (A1) e 24 horas após a terceira dose (A2). Resultados: O LH não apresentou elevação significativa nos quatro grupos. O FSH elevou-se nos quatro grupos de forma progressiva e semelhante. O estradiol elevou-se significativamente nos grupos de pacientes com hiperplasia congênita das supra-renais (p=0,005) e de pacientes com hermafroditismo verdadeiro (p=0,031), enquanto a testosterona elevou-se nos grupos com criptorquidia isolada (p=0,027) e de pacientes com ambigüidade genital sem etiologia definida (p=0,028). A inibina A elevou-se significativamente nos grupos de pacientes com hiperplasia congênita das supra-renais (p=0,005) e com hermafroditismo verdadeiro (p=0,043). Conclusão: O teste de estímulo com LH e FSH mostrou-se útil para o diagnóstico da presença de tecido ovariano tanto em pacientes com hiperplasia congênita das supra-renais, como naqueles com hermafroditismo verdadeiro. / Introduction: True hermaphrodism (TH) is characterized by the presence of ovarian and testicular tissue in the same patient comprises 5% of the intersex cases. A large spectrum of phenotypical variation is observed, ranging from normal female genitalia to normal male genitalia, covering a wide range of intermediary presentations, it becomes very difficult to make the diagnosis of TH on clinical basis. The detection of testicular tissue is well stablished but there is no available test to demonstrate the presence of ovarian tissue. Objectives: 1. To evaluate the effectiveness of the LH/FSH gonadal stimulation in demonstrating ovarian functiom 2. To evaluate the presence of ovarian tissue in intersex patients under gonadotropic stimulation and 3. To make the TH diagnosis before the surgical procedure. Patients and Methods: Ten patients with congenital adrenal hyperplasia (CAH), 10 with unilateral cryptorchidism, 13 intersex patients with no defined etiology, and seven TH patients have been included in the study. All the patients had a gonadotropic stimulation test with human menopausal gonadotropin (menotropin-hMG),150 IU, intramuscular, for three consecutive days. LH, FSH, estradiol, testosterone, and Inhibin A were measured before (0 time), 24h after the first gonadotropin dose, and 24h after the third gonadotropin dose. Results: LH did not show any significant increase in the four groups studied. FSH increased in the four groups in a similar way. Estradiol increased in CAH pacients (p=0.005) and in TH patients (p=0,031), while testosterone increased in patients whit unilateral cryptorchidism (p=0.027) as well as in the intersex patients without defined etiology. Inhibin A levels increased in CAH patients (p=0.005) and in the TH patients (p=0.043). Conclusion: The LH/FSH stimulation test demonstrated to be a useful method to diagnose the presence of ovarian tissue in CAH patients as well as in TH patients, becoming an important tool to diagnose TH even before the surgical procedure and histologic studies of the gonads.

Hermaphroditism, associated with territoriality and dominance behavior, is common in the marine environment. Male sex-specific coloration patterns and behavior are particularly evident in species where males are territorial and guard harems of females such as wrasses and groupers. Protogynous hermaphrodites that change sex from female to male are good models to study sexual behavior and related changes in the brain due to their abilities to reorganize their sexual phenotype as adults. Two hormones produced in the brain and implicated in the process of sex-specific behavior and reproductive development are arginine vasotocin (AVT) and gonadotropin releasing hormone (GnRH). While a wealth of data exists regarding these hormone systems separately, little is known about linkage between these two systems. Especially there is no data tracking these two systems together in any protogynous fish. This study was conducted to test the hypothesis that coordinated interactions between AVT and GnRH facilitate the process of behavioral and gonadal sex change in the rock hind Epinephelus adscensionis. Four topics were addressed to investigate the relationship between behavior and reproduction: i) rock hind sex change, sexual characteristics and conditions causing sex change to occur in captivity were detailed as a basis for examining the AVT system and GnRH during this process, ii) the distribution of a vasotocin V1a type receptor identified in rock hind brain was examined for the first time in a fish species using a custom designed antibody then the receptor protein was co-localized with GnRH producing cells within the brain to confirm that a pathway exists for AVT action on GnRH, iii) levels of AVT, AVT receptors, and GnRH messenger RNA (mRNA) were compared between male and female rock hind phenotypes, and iv) female rock hind at early stages of sex change were compared for brain mRNA expression of AVT, AVT receptors, and GnRH to determine the order of hormonal change during the process of sexual inversion in this species. This study provides a better understanding of the relationship between sex-specific behavior and reproductive development via AVT and GnRH systems that are conserved in all vertebrates. / text

Objetivo: Avaliar os resultados da genitoplastia masculinizante, com a técnica de Denis Browne, realizada em um grande grupo de pacientes com distúrbios do desenvolvimento sexual (DDS) tratados em um único hospital de referência. Pacientes e Métodos: Avaliamos 65 pacientes (57 com DDS 46,XY e 8 com DDS 46,XX) com hipospádia proximal e genitália ambígua. Os resultados cosméticos e sintomas urinários foram avaliados objetivamente e os pacientes responderam a um questionário sobre sintomas urinários, atividade sexual e satisfação pessoal após o tratamento cirúrgico. A idade dos pacientes na primeira cirurgia foi em média de 9 ± 10 anos e o segundo tempo cirúrgico foi realizado em média 14,5 ± 16,3 meses após a primeira cirurgia. O seguimento destes pacientes foi em média de 15,1 ± 10 anos e a idade dos pacientes na avaliação final foi em média de 25,9 ± 14,1 anos. Resultados: O aspecto cosmético foi considerado bom em 44%, regular em 53% e ruim em 3% dos pacientes. Houve diferença estatisticamente significante na média do tamanho peniano antes do tratamento entre os grupos com deficiência de 5-RD2 e com DDS de etiologia indeterminada (p<0,05). A média do tamanho peniano na avaliação final dos pacientes póspúberes foi de 7,8 ±2,4 cm, variando de 4 to 12 cm correspondendo a -4,4 ± 1,3 DP (-6,5 a -1,5 DP). Houve diferença estatisticamente significante no tamanho peniano entre os grupos com deficiência na produção de testosterona e com deficiência de 5-RD2 e entre os grupos com DDS de etiologia indeterminada e deficiência de 5-RD2 (p<0,05). O grupo com deficiência de 5-RD2 apresentou o menor tamanho peniano na avaliação final (-5,4±1 DP). As complicações mais freqüentes foram a fistula uretral encontradas em 50% dos pacientes seguida de estenose, presente em 20% dos pacientes. O sintoma urinário mais freqüente foi a perda urinária pós miccional. A atividade sexual foi referida por 86% dos pacientes adultos sendo definida como adequada em 60%, satisfatória em 29% e insatisfatória em 11% dos pacientes. Em relação ao resultado cirúrgico, 84% dos pacientes referiram estar satisfeitos porem 11% estavam insatisfeitos com o tamanho peniano e 5% com a presença de estenose uretral. Conclusão: A maioria dos pacientes com DDS submetidos a genitoplastia masculinizante pela técnica de Denis Browne mostrou-se satisfeita com os resultados cirúrgicos. Entretanto, queixas sobre o tamanho peniano, atividade sexual e micção indicam que novas abordagens devem ser desenvolvidas para melhor resultado morfológico e funcional dos pacientes com distúrbio do desenvolvimento sexual. / Purpose: To evaluate the results of masculinizing genitoplasty with the Denis Browne technique performed in a large cohort of patients with disorders of sex development (DSD) treated at a single tertiary centre. Patients and Methods: We evaluated 65 patients (57 with 46,XY DSD and 8 with 46,XX DSD) with proximal hypospadias and genital ambiguity. Cosmetic results and the urinary stream were evaluated objectively, and the patients responded questionnaires regarding satisfaction with the surgical results, as well as urinary and sexual symptoms. The age at first surgery was 9±10 years and the second stage was performed after 14.5±16.3 months. The mean followup was 15.1±10 years and the average patients age at the last examination was 25.9±14.1 years. Results: Cosmetic results were considered good in 44%, regular in 53% and poor in 3% of the cases. The comparison of the mean penile length among 46,XY DSD groups identified a significant statistically difference between 5-RD2 deficiency and undetermined DSD groups at diagnosis (p<0.05). The mean penile length at last clinical evaluation in post-pubertal patients was 7.8 ±2.4 cm, ranging from 4 to 12 cm corresponding to -4,4 ± 1,3 SD (-6.5 to -1.5 SD) and there was a significant statistically difference in the mean penile length amongst testosterone production deficiency and undetermined DSD groups with 5-RD2 deficiency group (p<0.05). The 5RD2 deficiency group presented the smallest penile length at the last evaluation (-5.4±1 SD). The most common complications were urethral fistula (50%) and stenosis (20%) and the most frequent urinary symptom was dribbling after micturition. Sexual activity was reported by 86% of adult patients and was adequate in 60%, satisfactory in 29% and unsatisfactory in 11% of them. Overall, 84% referred satisfaction with surgical results, but 11% complained about penile length and 5% about urethral stenosis. Conclusion: Most of the DSD patients were satisfied with the longterm results of masculinizing genitoplasty using Denis Browne technique, although specific complaints about small penis size, sexual activity and urinary symptoms were frequent. New approaches should be developed to achieve full satisfaction of DSD patients in adulthood.

Synalpheus shrimp species of the gambarelloides group are the only marine organisms displaying the highest level of social functioning, eusociality. Their social hierarchies are equally complex compared to the reproductive abnormalities that have been recently discovered. For instance, snapping shrimp of the genus Synalpheus were thought to be gonochoric, i.e. developing as independent sexes, until scanning electron microscopy studies revealed intersexed gonopores in several species. This project analyzed both the species composition, and accompanying reproductive structures, of Synalpheus spp. (Caridea: Alpheidae) comprised of densely aggregating communal and pair-living colonies in the Florida Keys, Florida. Colonies of pair-living and communal Synalpheus spp. were observed from hosts Spheciospongia vesparium and Spongia sp. from hard bottom assemblages of the Florida Reef Tract in order to assess differing population structures. Comparisons were made of the measures of overall and relative abundance, frequency by species and sex category, and variation in growth by species and sex category, for each individual colony. We then used scanning electron microscopy (SEM) images to determine the secondary sexual characteristics of three species (Synalpheus brooksi, S. herricki, and S. cf. herricki) which range in social behavior. Species were widely consistent in both host choice and distribution, across all sampling areas. The abundance of communal species Synalpheus brooksi was much greater than expected at all sites, in comparison to previously published work. While Synalpheus longicarpus was reported at higher frequencies in prior studies, our results yielded a much lower frequency of this species, often found in pairs, rather than dense aggregations. Average sizes of ovigerous and non-ovigerous individuals in dense colonies of Synalpheus brooksi and S. pectiniger did not differ significantly. However, total body length of individuals differed within species groups, specifically related to sex and presence of ova. Within colonies of S. brooksi, mid-development, or ‘transitional’ individuals, were discovered in nearly all populations. However, the reproductive and social function of these individuals displaying mixed sexual characteristics could not be determined from this study. Individuals of S. brooksi displaying ‘transitional’ external morphology, i.e. masculine abdominal pleura paired with clutches of eggs, displayed higher incidences of intersex gonopores per colony than did conspecific non-ovigerous and ovigerous individuals. These results suggest that colonies of S. brooksi may be comprised of a subset of helpers, or individuals undergoing a transitional sexual development phase, similar to prior published findings of intersexed helpers among eusocial colonies (Toth and Bauer 2007). In comparison to S. brooksi colonies, nearly all colonies of S. herricki and S. cf. herricki were composed of intersex individuals. In conjunction with previous instances documented in eusocial Synalpheus paraneptunus groups, the data provide substantial evidence of intersexing at all levels of social organization in Synalpheus spp. (pair living, communal, and eusocial). These findings nonetheless provide a clearer picture of how social structure and life history influence adaptation of a particular reproductive strategy. Quantifying features of Spheciospongia vesparium populations and comparing results to neighboring hosts, such as Spongia sp., provided evidence for potential influences of host choice, and variation in growth and reproductive capacity temporally and spatially. These observations of species’ growth patterns and abundances contribute greatly to our understanding of life history of Synalpheus spp., and, furthermore, adaptation of social organization.

La théorie de la sélection sexuelle a été largement élaborée à partir du constat de dimorphisme sexuel chez les espèces à sexes séparés. Une de ses caractéristiques générales est une sélection plus forte pour l'augmentation du nombre de partenaires sexuels chez les mâles que chez les femelles qui résulterait d'un investissement différentiel dans les descendants entre les deux sexes (anisogamie). Si hermaphrodisme et sélection sexuelle sont considérés comme compatibles depuis les travaux de Charnov (1979), les études sur le sujet restent rares que ce soit chez des animaux ou des plantes. Une raison importante est que la méthodologie disponible pour quantifier la sélection sexuelle ne prend pas en compte les particularités des hermaphrodites (par ex., corrélations ou effets croisés entre les deux fonctions sexuelles d'un même individu, autofécondation). Le premier objectif de cette thèse est de combler cette lacune méthodologique en proposant un cadre travail adapté aux hermaphrodites, que nous appliquons dans une étude empirique chez Physa acuta, un gastéropode hermaphrodite d'eau douce. Nous observons que la sélection sexuelle est plus intense sur la fonction mâle, comme généralement chez les espèces gonochoriques. Par ailleurs, nous ne détectons aucun effet des particularités des hermaphrodites dans cette expérience. Dans un deuxième temps, nous nous intéressons de manière plus détaillée aux composantes du succès reproducteur mâle (RSm). Nous montrons que chez P. acuta il existe une priorité spermatique au premier partenaire mâle lorsque plusieurs individus sont en compétition. Enfin, nous proposons une décomposition de la variance de RSm en ses composantes pré- et post-copulatoires, qui représentent respectivement 60 et 40% de la variance. Dans la troisième partie, nous intégrons la sélection sexuelle à l'étude de l'évolution de l'allocation sexuelle d'un hermaphrodite, via une approche d'évolution expérimentale chez P. acuta. Menée sur plus de 10 générations, elle vise à faire évoluer l'allocation sexuelle de manière disruptive (lignées mâle ou femelle) en sélectionnant les composantes mâle et femelle du succès reproducteur. Les résultats préliminaires suggèrent qu'il est possible de manipuler l'allocation sexuelle chez un hermaphrodite simultané en sélectionnant sur son régime d'appariement. Nous concluons que l'anisogamie suffit à justifier l'existence de la sélection sexuelle sans avoir à supposer un dimorphisme sexuel. Son étude chez les hermaphrodites simultanés ouvre des perspectives pour la compréhension du rôle de l'allocation sexuelle dans l'évolution des systèmes de reproduction. / A cornerstone of the theory of sexual selection in gonochoric species is sexual dimorphism. A very general result is stronger selection on males than on females for increasing mating success, and this fundamentally relies on differential investment in offspring between the sexes (anisogamy). Although sexual selection does operate in hermaphroditic species as well, few empirical studies have been performed whether in animals or in plants. The main reason is that the current framework for studying sexual selection does not incorporate the particularities of hermaphrodites, including correlations or cross-sex effects between sex functions and self-fertilization. The first goal of this thesis is to fill this gap by proposing an appropriate framework for hermaphrodites (generalizing that available for gonochoric species). It was applied to approach sexual selection in the hermaphroditic freshwater gastropod Physa acuta. Sexual selection turns out to be stronger on the male than on the female function, as classically observed in gonochorists. Moreover, we do not detect any effect in relation to hermaphrodites' particularities. We then focus on the components of male reproductive success (RSm) in more details. We detect a pattern of sperm precedence in conditions of sperm competition. We develop a new method for decomposing the variance in RSm into pre- and post-copulatory components (representing 60 and 40% of the variance respectively). The third section aims at integrating sexual selection in studies of sex allocation and its evolution. It relies on a protocol of experimental evolution in P. acuta. Conducted over more than 10 generations. Its aim is to observe the evolution of sex allocation by disruptively selecting male and female components of reproductive success. Preliminary results indeed suggest that it is possible to manipulate sex allocation in a simultaneous hermaphrodite by manipulating its mating system. We conclude that anisogamy alone is a sufficient condition for sexual selection to proceed, and that sexual dimorphism is not required. Study sexual selection in simultaneous hermaphrodites gives insights for understanding the role of sex allocation in the evolution of mating systems.

Made available in DSpace on 2014-12-17T14:10:29Z (GMT). No. of bitstreams: 1 NirleiHCB_DISSERT.pdf: 6542994 bytes, checksum: b970fd5055cebafb782b426aa47838fa (MD5) Previous issue date: 2012-03-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Reproductive strategy of the hermaphrodite fish the marbled swamp eel, Synbranchus marmoratus (Bloch, 1795) (Osteichthyes: Synbranchidae) was investigated in the Marechal Dutra reservoir, Acari, Rio Grande do Norte, using fish samples captured monthly during the period of July 2010 to July 2011. The limnological parameters and rainfall were verified. The captured fish specimens were numbered, weighed, measured, dissected and their gonads and liver were removed, weighed and identified as to sex and developmental stages of gonads. The length-weight relationship was determined for grouped sex. The size of first gonadal maturation, gonadosomatic index (GSI), condition factor (K) and hepatosomatic index (HSI) were calculated. The development stages of the gonads were investigated using macroscopic and histological techniques, besides the fecundity and reproductive period. The macroscopic characteristics and the histological development of gonads confirmed the four different sexual types in the sampled population: primary males, females, intersex and secondary males. The secondary males were bigger and heavier than all the other types. This species showed a negative allometric growth with a higher increase in length than weight. The size at which 50% of the females began the process of gonadal maturation was 43.5 cm of total length, and for secondary males it was 58.5 cm. Condition factor showed two peaks in February and in April 2011. IGS indicated a reproductive period from July to September 2010 and was negatively correlated with the condition factor and rainfall. IGS showed a negative correlation when compared with the condition factor and the rainy season. HSI was highest in February ad lowest in December. The reproductive period of this species occurs between the end of the rainy season and the beginning of the dry season. S. marmoratus presents a seasonal reproductive strategy which optimizes its reproductive success under the semiarid climatic conditions / A estrat?gia reprodutiva do peixe hermafrodita mussum, Synbranchus marmoratus (Bloch, 1795) (Osteichthyes: Synbranchidae) foi investigada no a?ude Marechal Dutra, Acari, Rio Grande do Norte, utilizando os exemplares capturados mensalmente no per?odo de julho de 2010 a julho de 2011. Foram verificados os par?metros limnol?gicos e a pluviosidade. Os exemplares capturados foram numerados, pesados, medidos, dissecados e o f?gado e as g?nadas foram retiradas, pesadas e identificadas quanto ao sexo e o est?dio de desenvolvimento gonadal. A rela??o peso-comprimento foi determinada para sexos agrupados. O tamanho da primeira matura??o, o ?ndice gonadossom?tico (IGS), o fator de condi??o (K) e o ?ndice hepatossom?tico (IHS) foram determinados. As fases do desenvolvimento das g?nadas foram investigadas usando t?cnicas macrosc?picas e histol?gicas, al?m de determinar a fecundidade e o per?odo reprodutivo da esp?cie. As caracter?sticas macrosc?picas e histol?gicas de desenvolvimento gonadal confirmaram os quatro tipos sexuais diferentes na popula??o dos peixes capturados, sendo: machos prim?rios, f?meas, intersexos e machos secund?rios. Os machos secund?rios apresentaram os maiores valores de comprimento total e peso total. A esp?cie mostrou um crescimento do tipo alom?trico negativo com maior incremento em comprimento do que em peso. O tamanho em que 50% da popula??o das f?meas iniciaram o processo de matura??o gonadal foi de 43,5 cm de comprimento total e para os machos secund?rios foi de 58,5 cm. O fator de condi??o apresentou dois picos, um no m?s de fevereiro e outro m?s de abril de 2011. IGS indicou um per?odo de reprodu??o durante julho a setembro de 2010, mostrando correla??o negativa ao fator de condi??o. IHS mostrou um pico no m?s de fevereiro com o menor valor no m?s de dezembro coincidindo com o per?odo de seca da regi?o. A esp?cie apresenta um per?odo reprodutivo entre o final das chuvas e o in?cio da seca. S. marmoratus mostra uma estrat?gia reprodutiva sazonal que aperfei?oa seu sucesso reprodutivo dentro das condi??es clim?ticas do semi?rido. Palavras chave: mussum, Synbranchus marmoratus, estrat?gia reprodutiva, hermafroditismo, a?ude do semi?rido

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