Spelling suggestions: "subject:"spermatophore"" "subject:"spermatophores""
1 |
INFLUENCE OF ENVIRONMENTAL FEATURES ON SPERMATOPHORE PLACEMENT IN SPOTTED SALAMANDERS (AMBYSTOMA MACULATUM)Kuechle, Megan A 01 January 2019 (has links)
Successful reproduction in salamanders is driven by behavioral, environmental, and temporal interactions among adults. While much of our understanding of salamander mating systems is based upon either courtship behavior of both sexes or aspects of female choice, the decisions made by males regarding where to place spermatophores is much less quantified. In this study, we mapped male spermatophore placement in the spotted salamander (Ambystoma maculatum) with respect to ecological and spatial locations within a vernal pool complex in Charles City County, Virginia. The overall goal was to use the spatial and ecological placement of spermatophores to determine if individuals deposit spermatophores randomly within the vernal pool or if males exhibited specific preferences for deposition. Using comprehensive surveys of the vernal pools and individual spermatophores within a 0.5m2 grid and terrestrial LIDAR, a total of 218 spermatophores were identified and mapped. We repeated these surveys for two successive breeding seasons. Placement occurred at an intermediate depth and an intermediate distance to the edge. Males also preferred to place spermatophores on leaf substrate as opposed to sticks or conifer needles. The physical placement of spermatophores exhibited autocorrelation in space during single reproductive events as well as across breeding seasons. These results suggest that males actively select for specific locations within a pool for spermatophore placement-a proverbial Goldilocks zone-which may be consistent with increased reproductive success. This information is key to understanding salamander mating system parameters in this species and may contribute to developing more effective management strategies.
|
2 |
Influence de la plante hôte sur les performances sexuelles des mâles et conséquences sur le potentiel reproductif des femelles phytophages / Effect of host plant quality on male sexual performances and consequences on female reproductive output in a phytophagous mothMuller, Karen 13 May 2016 (has links)
L’abondance des insectes phytophages est déterminée par l’influence de facteurs biotiques et abiotiques qui affectent leurs traits d’histoire de vie. Chez les espèces phytophages à reproduction sur capital, la qualité de la plante hôte sur laquelle les individus effectuent leur développement larvaire est un facteur critique affectant le succès reproducteur des adultes. Curieusement, si l’effet de la plante hôte sur le potentiel reproductif des femelles a été largement décrit, il n’a été que peu étudié sur celui des mâles. Par ailleurs, chez les lépidoptères, lors de l’accouplement, la femelle reçoit du mâle un cadeau nuptial sous la forme d’un spermatophore contenant des spermatozoïdes ainsi que des sécrétions produites par les glandes accessoires. Ces sécrétions constituent des bénéfices directs pour la femelle qui pourra les remobiliser pour augmenter sa fécondité. Mon projet de thèse vise à déterminer l’influence de la plante hôte sur les performances reproductives des mâles et d’en évaluer les conséquences sur le potentiel reproductif des femelles et sur l’évolution des stratégies de choix de partenaire chez un papillon ravageur de la vigne, l’Eudémis (Lobesia botrana). Les expériences menées au cours de ces trois années de thèse révèlent que la nutrition larvaire sur différents cépages de vigne module fortement les réserves énergétiques des mâles, affectant leur potentiel reproductif à travers la taille et le contenu des spermatophores qu’ils transfèrent aux femelles pendant l’accouplement. De plus, l’investissement du mâle dans la production de spermatophores décline au cours d’accouplements successifs, les mâles n’étant capables de produire qu’un seul spermatophore riche en nutriments au cours de leur vie. Ces deux facteurs (nutrition larvaire et expérience sexuelle), qui affectent fortement la qualité reproductive des mâles, ont d’importantes conséquences sur le potentiel reproductif de leur partenaire. En effet, les femelles recevant des spermatophores riches en nutriments et en spermatozoïdes ont plus de descendants que celles recevant des spermatophores de moins bonne qualité. Enfin, les femelles semblent capables de discriminer parmi les mâles en se basant sur des critères reflétant leur qualité reproductive, s’accouplant préférentiellement avec ceux leur procurant le plus de bénéfices directs. Ainsi, les résultats de cette thèse confirment l’importance d’intégrer l’effet mâle quand on s’intéresse à l’évolution des populations de phytophages. De plus, identifier les facteurs écologiques modulant les interactions entre les partenaires sexuels chez les espèces menaçant les cultures est crucial pour pouvoir optimiser les programmes de gestion de ces ravageurs. / The abundance of phytophagous insects is determined by numerous interacting biotic and abiotic factors. In capital-breeding phytophagous insects, larval host plant quality is a key determinant of the adult phenotype and the performance of both males and females. Curiously, if the effect of host plant quality on female reproductive success is well-established, little effort has been conducted to determine this effect on male reproductive success. Moreover, in Lepidoptera, males transfer to females a spermatophore containing sperm and accessory gland products rich in nutrients that could be reinvested into female reproduction. The aim of this thesis was to evaluate how male larval nutrition on different host cultivars affects male reproductive traits which could, in turn, influence female reproductive output and mate choice strategies in an important grapevine pest, the European grapevine moth (Lobesia botrana). During these three years, we found that the host cultivar for the larvae strongly influences the energy reserves of male adult moths, affecting ultimately their reproductive potential through the size and content of spermatophores they transfer to females at mating. Moreover, male investment in the spermatophore declines over consecutives matings, suggesting that spermatophores are energetically expensive to produce in this monandrous capital breeding species. Thus ‘male quality’ depends on both the male larval origin and mating history, and females receiving protein-rich spermatophores at mating have an overall greater reproductive output than females mated with poor quality males producing less nutritionally rich spermatophores. Finally, females are able to discriminate among males and mate more with males having high sperm quality (virgin males or males from certain cultivars or geographical origins) to obtain substantial direct benefits.The results of this thesis confirm the importance of considering the “male effect” when trying to understand the evolution of phytophagous populations. Moreover, identifying the ecological conditions that influence the mating success of male and female in crop-pest species may lead to a better management of these crop pests.
|
3 |
Estrutura e funcionamento dos espermatóforos de Doryteuthis plei (Mollusca: Cephalopoda) e reavaliação da reação espermatofórica dos cefalópodes / Spermatophore structure and functioning in Doryteuthis plei (Mollusca: Cephalopoda), and a reappraisal of the cephalopod spermatophoric reactionMarian, José Eduardo Amoroso Rodriguez 17 June 2010 (has links)
Cefalópodes coleóides (lulas, sépias e polvos) produzem espermatóforos muito elaborados, os quais são transferidos à fêmea durante a cópula por meio de um apêndice modificado nos machos. Durante a transferência à fêmea, os espermatóforos sofrem, de forma autônoma, drásticas modificações na chamada \"reação espermatofórica\", complexo processo de evaginação do aparato ejaculatório, que conduz à exteriorização da massa espermática e corpo cimentante. Poucos trabalhos abordam com detalhes a morfologia e anatomia funcional dos espermatóforos dos cefalópodes, grande parte do conhecimento acerca da estrutura do espermatóforo tendo sido gerada por trabalhos clássicos do século XIX e início do século XX. Investigações acerca do funcionamento dos espermatóforos são consideravelmente mais raras, estando o conhecimento básico sobre a reação espermatofórica restrito a apenas 20 espécies de coleóides. Como o funcionamento extracorpóreo dos espermatóforos depende exclusivamente da intrincada estrutura e organização de seus componentes (e.g., membranas e túnicas), somente investigações detalhadas dessas estruturas proverão as bases para a compreensão do funcionamento e da exata função do complexo espermatóforo dos coleóides. Nesse contexto, a presente Tese, organizada em cinco capítulos, teve como objetivo principal investigar a estrutura e o funcionamento dos espermatóforos da lula Doryteuthis plei (Blainville, 1823). No primeiro capítulo, com o objetivo de se estudar a fundo a organização estrutural dos espermatóforos da espécie, diversas técnicas de microscopia foram testadas e empregadas. Como resultado da combinação de diferentes ferramentas de análise, a estrutura do espermatóforo revelou-se ainda mais complexa, sendo as principais descobertas referentes à: 1) elaborada estrutura da membrana mediana, organizada em camadas e apresentando um segmento aboral quimicamente distinto, que envolve parte do corpo cimentante; 2) presença de um material reticulado preenchendo o espaço entre a túnica interna e a membrana mediana (discute-se a possibilidade do mesmo consistir em um fluido viscoso em espermatóforos intactos); 3) presença de espículas intimamente associadas à membrana interna na região do corpo cimentante (além das espículas embebidas no filamento espiral); 4) presença de extensões membranosas que delimitam uma câmara pré-oral na região do capuz; e 5) complexa organização estrutural do corpo cimentante, delimitado por duas camadas e contendo substâncias de distintas propriedades químicas. Uma avaliação cuidadosa da literatura permite sugerir que pelo menos parte dessas características deva ser comum aos espermatóforos de outros loliginídeos, e, em alguns casos, de outros grupos de coleóides. Como parte da investigação acerca da reação espermatofórica e dos mecanismos envolvidos na fixação da massa espermática no corpo da fêmea, constatou-se que, sob condições artificiais, espermatóforos em evaginação são capazes de penetrar musculatura exposta, de forma similar ao fenômeno de \"implante profundo\" observado naturalmente em algumas lulas oceânicas. Esse resultado foi descrito no segundo capítulo, no qual foi levantada a hipótese de que um mecanismo de perfuração seria inerente à estrutura dos espermatóforos dos coleóides. Dando continuidade ao estudo da morfologia funcional dos espermatóforos de D. plei, o terceiro capítulo apresenta os resultados obtidos a partir da investigação do funcionamento do espermatóforo e da morfologia dos espermatângios (i.e, espermatóforos evertidos) obtidos in vitro, bem como daqueles naturalmente fixados na fêmea. As evidências reunidas permitem afirmar que o processo de fixação compreende distintas fases desempenhadas por diversos componentes do espermatóforo, contrariamente a um conceito anterior de que a fixação seria realizada somente por substâncias adesivas do corpo cimentante. Durante a reação espermatofórica, o aparato ejaculatório e respectivo filamento espiral são capazes de perfurar superficialmente ou escarificar o tecido-alvo. Subseqüentemente, o corpo cimentante sofre drástica modificação estrutural, resultando na extrusão de parte do conteúdo cimentante, o qual é injetado diretamente sobre o tecido perfurado. Além disso, o corpo cimentante é exteriorizado com uma extremidade afilada que, em alguns casos, foi encontrada firmemente implantada no tecido da fêmea, juntamente com as substâncias cimentantes. Concomitantemente ao processo de reconfiguração do corpo cimentante, a região da membrana interna que contém as espículas no espermatóforo intacto é evertida e estirada sobre a base do espermatângio, sugerindo um papel auxiliar no processo de fixação. Com base em evidências da literatura, bem como nas obtidas no âmbito da presente Tese, no quarto capítulo propõe-se um modelo teórico para explicar como o aparato ejaculatório em evaginação seria capaz de perfurar e implantar-se no corpo da fêmea durante a reação espermatofórica. Sugere-se que a perfuração seria mecânica e resultado da ação conjunta do aumento gradual do diâmetro dos anéis do filamento espiral e da distância entre os mesmos, bem como do poder de ancoragem proporcionado pelas respectivas espículas. Finalmente, o quinto capítulo apresenta uma revisão da literatura acerca do fenômeno de implante de espermatóforos em Decapodiformes, e reúne evidências que corroboram o modelo teórico proposto. Neste capítulo, é apresentada também uma reinterpretação da função da reação espermatofórica em Octopodiformes. Com base no levantamento de diversos caracteres reprodutivos, foi possível testar hipóteses de evolução da estrutura do espermatóforo e do sistema de implante dos espermatângios, bem como hipóteses de co-evolução de estruturas envolvidas no processo de transferência e armazenamento de espermatozóides. Duas hipóteses principais acerca da evolução do sistema de implante dos espermatângios são propostas. / Male coleoid cephalopods produce elaborate spermatophores, which are transferred to the female during mating. These spermatophores are capable of functioning autonomously and extracorporeally, undergoing complicated changes during the so-called spermatophoric reaction, i.e., a complex process of evagination of the spermatophoric tunics and membranes that, ultimately, leads to the extrusion and attachment of the sperm mass on the females body. Few detailed morphological studies regarding this structure have yet been conducted, and much of the knowledge on the coleoid spermatophore was generated by classical studies of the 19th and early 20th centuries; furthermore, investigations on the functioning of this structure are even rarer. Since the extracorporeal functioning of coleoid spermatophores must rely entirely on the intricate structure and organization of the tunics, membranes, and other structures composing the spermatophore, only detailed investigations of these components would provide the basis for comprehending its mechanics. On these grounds, the present five-chapter Thesis aimed to provide solid evidence that could allow for postulating hypothesis on the functioning and evolution of this unique structure. In the first chapter, an investigation of the morphology of the spermatophore of Doryteuthis plei (Blainville, 1823) applying several microscopy techniques was carried on. A much more complex structural arrangement was revealed for the loliginid spermatophore, the most striking findings being: 1) the complex, layered structure of the middle membrane, which bears an additional, chemically distinct segment surrounding part of the cement body; 2) the presence of a space between the inner tunic and middle membrane filled with a fine reticulated material, presumably a viscous fluid in the fresh state; 3) the presence of stellate particles not only embedded in the spiral filament, but also closely applied to the inner membrane at the level of the cement body; 4) the presence of a pre-oral chamber in the cap region; and 5) the complex organization of the cement body, formed by two distinct layers encompassing contents of different chemical and textural properties. Careful literature reassessment suggests several of these features are common to loliginids, and to some extent to other squids. Their possible functional implications are discussed in light of our knowledge on the spermatophoric reaction mechanics. As part of the investigation on the spermatophoric reaction, and the mechanisms involved in the attachment of the sperm mass on the females body, it was found that the everting spermatophore, when directed towards the incised region of an experimental tissue sample, was able to readily penetrate the artificially exposed musculature, almost resembling natural deep implantation observed in some oceanic and deep-sea squids; this finding is reported in the second chapter, where it was hypothesized that the mechanism involved in deep implantation could be inherent to the 215 spermatophore structure of all squids. The third chapter investigated the functional morphology of the spermatophore of the squid D. plei applying in vitro analysis of the reaction, as well as light and electron microscopy investigation of spermatangia (everted spermatophores containing the sperm mass) obtained either in vitro or naturally attached on the female. Hitherto unnoticed functional features of the loliginid spermatophore revealed herein required a reappraisal of some important processes involved in the spermatophoric reaction, as well as the proposal of new hypotheses to explain their mechanics. The most striking findings concern to the attachment mechanism, which is not carried out solely by cement adhesive material, as previously believed, but rather by a complex process performed by multiple structures that lead to the implantation of the base of the spermatangium into the female body. Firstly, the everting ejaculatory apparatus is presumably able to superficially puncture the female tissue. Subsequently to this process, the cement body passes through a complex structural rearrangement, which leads to the injection of both its viscid cement contents and pointed oral region through the puncture into the female tissue. When the inner membrane at the oral region of the cement body is everted, its sharp stellate particles are exposed, presumptively adhering to the scarified tissue and augmenting attachment by assuring the injection of the cement material inside the superficial hole. The functioning of the loliginid spermatophore is revisited in light of these findings. The forth chapter, building upon evidence from the literature along with evidence from these experiments, proposes a theoretical model to explain how the everting ejaculatory apparatus would be able to mechanically perforate, and concomitantly implant the spermatophore into the female body during the spermatophoric reaction. It is proposed that this process is achieved chiefly through the combination of 1) an \"evaginating-helix\" mechanism performed by the everting ejaculatory apparatus\' spiral filament, and 2) the anchorage provided by its numerous, minute sharp stellate particles. Finally, the fifth chapter reviews the literature concerning the phenomenon of implantation of spermatophores in decapodiforms, and presents evidence corroborating the proposed theoretical model ascribing the role of implantation to the mechanical perforation performed by the spiral filament. The mechanisms of spermatophore transfer are also reviewed for octopodiforms, and a reinterpretation of the function of the spermatophoric reaction in this case is provided. In light of parsimonious character optimizations performed onto recently published phylogenetic trees, a complete ejaculatory apparatus with a spiral filament, as well as the spermatophoric reaction, apparently emerged once and early in the evolution of the Coleoidea. This novelty possibly provided an efficient attachment mechanism and presumably countered the changes associated with the adoption of an active mode of life by coleoids, augmenting fertilization success. Two main hypotheses for the evolution of the complex spermatophore within Coleoidea and Decapodiformes are proposed.
|
4 |
Estrutura e funcionamento dos espermatóforos de Doryteuthis plei (Mollusca: Cephalopoda) e reavaliação da reação espermatofórica dos cefalópodes / Spermatophore structure and functioning in Doryteuthis plei (Mollusca: Cephalopoda), and a reappraisal of the cephalopod spermatophoric reactionJosé Eduardo Amoroso Rodriguez Marian 17 June 2010 (has links)
Cefalópodes coleóides (lulas, sépias e polvos) produzem espermatóforos muito elaborados, os quais são transferidos à fêmea durante a cópula por meio de um apêndice modificado nos machos. Durante a transferência à fêmea, os espermatóforos sofrem, de forma autônoma, drásticas modificações na chamada \"reação espermatofórica\", complexo processo de evaginação do aparato ejaculatório, que conduz à exteriorização da massa espermática e corpo cimentante. Poucos trabalhos abordam com detalhes a morfologia e anatomia funcional dos espermatóforos dos cefalópodes, grande parte do conhecimento acerca da estrutura do espermatóforo tendo sido gerada por trabalhos clássicos do século XIX e início do século XX. Investigações acerca do funcionamento dos espermatóforos são consideravelmente mais raras, estando o conhecimento básico sobre a reação espermatofórica restrito a apenas 20 espécies de coleóides. Como o funcionamento extracorpóreo dos espermatóforos depende exclusivamente da intrincada estrutura e organização de seus componentes (e.g., membranas e túnicas), somente investigações detalhadas dessas estruturas proverão as bases para a compreensão do funcionamento e da exata função do complexo espermatóforo dos coleóides. Nesse contexto, a presente Tese, organizada em cinco capítulos, teve como objetivo principal investigar a estrutura e o funcionamento dos espermatóforos da lula Doryteuthis plei (Blainville, 1823). No primeiro capítulo, com o objetivo de se estudar a fundo a organização estrutural dos espermatóforos da espécie, diversas técnicas de microscopia foram testadas e empregadas. Como resultado da combinação de diferentes ferramentas de análise, a estrutura do espermatóforo revelou-se ainda mais complexa, sendo as principais descobertas referentes à: 1) elaborada estrutura da membrana mediana, organizada em camadas e apresentando um segmento aboral quimicamente distinto, que envolve parte do corpo cimentante; 2) presença de um material reticulado preenchendo o espaço entre a túnica interna e a membrana mediana (discute-se a possibilidade do mesmo consistir em um fluido viscoso em espermatóforos intactos); 3) presença de espículas intimamente associadas à membrana interna na região do corpo cimentante (além das espículas embebidas no filamento espiral); 4) presença de extensões membranosas que delimitam uma câmara pré-oral na região do capuz; e 5) complexa organização estrutural do corpo cimentante, delimitado por duas camadas e contendo substâncias de distintas propriedades químicas. Uma avaliação cuidadosa da literatura permite sugerir que pelo menos parte dessas características deva ser comum aos espermatóforos de outros loliginídeos, e, em alguns casos, de outros grupos de coleóides. Como parte da investigação acerca da reação espermatofórica e dos mecanismos envolvidos na fixação da massa espermática no corpo da fêmea, constatou-se que, sob condições artificiais, espermatóforos em evaginação são capazes de penetrar musculatura exposta, de forma similar ao fenômeno de \"implante profundo\" observado naturalmente em algumas lulas oceânicas. Esse resultado foi descrito no segundo capítulo, no qual foi levantada a hipótese de que um mecanismo de perfuração seria inerente à estrutura dos espermatóforos dos coleóides. Dando continuidade ao estudo da morfologia funcional dos espermatóforos de D. plei, o terceiro capítulo apresenta os resultados obtidos a partir da investigação do funcionamento do espermatóforo e da morfologia dos espermatângios (i.e, espermatóforos evertidos) obtidos in vitro, bem como daqueles naturalmente fixados na fêmea. As evidências reunidas permitem afirmar que o processo de fixação compreende distintas fases desempenhadas por diversos componentes do espermatóforo, contrariamente a um conceito anterior de que a fixação seria realizada somente por substâncias adesivas do corpo cimentante. Durante a reação espermatofórica, o aparato ejaculatório e respectivo filamento espiral são capazes de perfurar superficialmente ou escarificar o tecido-alvo. Subseqüentemente, o corpo cimentante sofre drástica modificação estrutural, resultando na extrusão de parte do conteúdo cimentante, o qual é injetado diretamente sobre o tecido perfurado. Além disso, o corpo cimentante é exteriorizado com uma extremidade afilada que, em alguns casos, foi encontrada firmemente implantada no tecido da fêmea, juntamente com as substâncias cimentantes. Concomitantemente ao processo de reconfiguração do corpo cimentante, a região da membrana interna que contém as espículas no espermatóforo intacto é evertida e estirada sobre a base do espermatângio, sugerindo um papel auxiliar no processo de fixação. Com base em evidências da literatura, bem como nas obtidas no âmbito da presente Tese, no quarto capítulo propõe-se um modelo teórico para explicar como o aparato ejaculatório em evaginação seria capaz de perfurar e implantar-se no corpo da fêmea durante a reação espermatofórica. Sugere-se que a perfuração seria mecânica e resultado da ação conjunta do aumento gradual do diâmetro dos anéis do filamento espiral e da distância entre os mesmos, bem como do poder de ancoragem proporcionado pelas respectivas espículas. Finalmente, o quinto capítulo apresenta uma revisão da literatura acerca do fenômeno de implante de espermatóforos em Decapodiformes, e reúne evidências que corroboram o modelo teórico proposto. Neste capítulo, é apresentada também uma reinterpretação da função da reação espermatofórica em Octopodiformes. Com base no levantamento de diversos caracteres reprodutivos, foi possível testar hipóteses de evolução da estrutura do espermatóforo e do sistema de implante dos espermatângios, bem como hipóteses de co-evolução de estruturas envolvidas no processo de transferência e armazenamento de espermatozóides. Duas hipóteses principais acerca da evolução do sistema de implante dos espermatângios são propostas. / Male coleoid cephalopods produce elaborate spermatophores, which are transferred to the female during mating. These spermatophores are capable of functioning autonomously and extracorporeally, undergoing complicated changes during the so-called spermatophoric reaction, i.e., a complex process of evagination of the spermatophoric tunics and membranes that, ultimately, leads to the extrusion and attachment of the sperm mass on the females body. Few detailed morphological studies regarding this structure have yet been conducted, and much of the knowledge on the coleoid spermatophore was generated by classical studies of the 19th and early 20th centuries; furthermore, investigations on the functioning of this structure are even rarer. Since the extracorporeal functioning of coleoid spermatophores must rely entirely on the intricate structure and organization of the tunics, membranes, and other structures composing the spermatophore, only detailed investigations of these components would provide the basis for comprehending its mechanics. On these grounds, the present five-chapter Thesis aimed to provide solid evidence that could allow for postulating hypothesis on the functioning and evolution of this unique structure. In the first chapter, an investigation of the morphology of the spermatophore of Doryteuthis plei (Blainville, 1823) applying several microscopy techniques was carried on. A much more complex structural arrangement was revealed for the loliginid spermatophore, the most striking findings being: 1) the complex, layered structure of the middle membrane, which bears an additional, chemically distinct segment surrounding part of the cement body; 2) the presence of a space between the inner tunic and middle membrane filled with a fine reticulated material, presumably a viscous fluid in the fresh state; 3) the presence of stellate particles not only embedded in the spiral filament, but also closely applied to the inner membrane at the level of the cement body; 4) the presence of a pre-oral chamber in the cap region; and 5) the complex organization of the cement body, formed by two distinct layers encompassing contents of different chemical and textural properties. Careful literature reassessment suggests several of these features are common to loliginids, and to some extent to other squids. Their possible functional implications are discussed in light of our knowledge on the spermatophoric reaction mechanics. As part of the investigation on the spermatophoric reaction, and the mechanisms involved in the attachment of the sperm mass on the females body, it was found that the everting spermatophore, when directed towards the incised region of an experimental tissue sample, was able to readily penetrate the artificially exposed musculature, almost resembling natural deep implantation observed in some oceanic and deep-sea squids; this finding is reported in the second chapter, where it was hypothesized that the mechanism involved in deep implantation could be inherent to the 215 spermatophore structure of all squids. The third chapter investigated the functional morphology of the spermatophore of the squid D. plei applying in vitro analysis of the reaction, as well as light and electron microscopy investigation of spermatangia (everted spermatophores containing the sperm mass) obtained either in vitro or naturally attached on the female. Hitherto unnoticed functional features of the loliginid spermatophore revealed herein required a reappraisal of some important processes involved in the spermatophoric reaction, as well as the proposal of new hypotheses to explain their mechanics. The most striking findings concern to the attachment mechanism, which is not carried out solely by cement adhesive material, as previously believed, but rather by a complex process performed by multiple structures that lead to the implantation of the base of the spermatangium into the female body. Firstly, the everting ejaculatory apparatus is presumably able to superficially puncture the female tissue. Subsequently to this process, the cement body passes through a complex structural rearrangement, which leads to the injection of both its viscid cement contents and pointed oral region through the puncture into the female tissue. When the inner membrane at the oral region of the cement body is everted, its sharp stellate particles are exposed, presumptively adhering to the scarified tissue and augmenting attachment by assuring the injection of the cement material inside the superficial hole. The functioning of the loliginid spermatophore is revisited in light of these findings. The forth chapter, building upon evidence from the literature along with evidence from these experiments, proposes a theoretical model to explain how the everting ejaculatory apparatus would be able to mechanically perforate, and concomitantly implant the spermatophore into the female body during the spermatophoric reaction. It is proposed that this process is achieved chiefly through the combination of 1) an \"evaginating-helix\" mechanism performed by the everting ejaculatory apparatus\' spiral filament, and 2) the anchorage provided by its numerous, minute sharp stellate particles. Finally, the fifth chapter reviews the literature concerning the phenomenon of implantation of spermatophores in decapodiforms, and presents evidence corroborating the proposed theoretical model ascribing the role of implantation to the mechanical perforation performed by the spiral filament. The mechanisms of spermatophore transfer are also reviewed for octopodiforms, and a reinterpretation of the function of the spermatophoric reaction in this case is provided. In light of parsimonious character optimizations performed onto recently published phylogenetic trees, a complete ejaculatory apparatus with a spiral filament, as well as the spermatophoric reaction, apparently emerged once and early in the evolution of the Coleoidea. This novelty possibly provided an efficient attachment mechanism and presumably countered the changes associated with the adoption of an active mode of life by coleoids, augmenting fertilization success. Two main hypotheses for the evolution of the complex spermatophore within Coleoidea and Decapodiformes are proposed.
|
5 |
Influence of variable environmental on population structure and reproductive biology focused on spermatophores of Octopus insularis / InfluÃncia de variÃveis ambientais na estrutura populacional e a biologia reprodutiva focada nos espermatÃforos do polvo, Octopus insularisBruno Braulino Batista 28 January 2016 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Octopus, are marine organisms belonging to the Filo Mollusca and are distributed around the world and are important to the marine ecosystem acting as opportunists and predators of great economic importance because it is part of several fishing. Although not yet know the extent to which these animals are able to withstand fishing pressure. In regard reproduction these organisms are dioecious with only playback (semelpareous), with high fertility with copulations. The paralavaes of O. insularis are planktonic, giving the species a high dispersal capacity. However, reproductive biology studies of O. insularis are still scarce, being restricted primarily to females and reproductive tract structures and size that these animals reach maturity. There is an absence of any information about the complex structure responsible for the fertilization of the oocytes in the case, the spermatophores. This work aims to analyze the influence of environmental variables in the population structure and reproductive biology focused on the spermatophores octopus, Octopus insularis. For this, we need to analyze the parameters of population biology, describe the spermatophore and describe the spermatophoric reaction. This thesis is divided in three chapters that discuss: 1) Population structure of Octopus insularis caught using longline pots related with environmental variables that had a significant body size variations in the rainy season, possibly related to the breeding period and was observed synchronism between the environmental variables and the life cycle of these animals. 2) Morphological description and functional anatomy from spermatophore of the Octopus insularis, which is divided into two structures sperm mass on aboral region being covered by the outer and middle layer and the ejaculatory apparatus that is separated by the granular liquid and the apparatus is covered by domestic and inner membrane coat, protecting the spiral filament. 3) Spermatophoric reaction in vitro octopus, Octopus insularis which lasts about 15 minutes starts with the outgrowth of ejaculatory apparatus and consequent release of sperm mass in the middle. / Polvos, sÃo organismos marinhos pertencentes ao Filo Mollusca e estÃo distribuÃdos ao redor do mundo, sendo importantes para o ecossistema marinho atuando como predadores oportunistas e de grande importÃncia econÃmica, pois faz parte de diversas pescaria. Embora, ainda nÃo se saiba atà que ponto estes animais consigam resistir à pressÃo da pesca. Com relaÃÃo a reproduÃÃo esses organismos sÃo diÃicos com reproduÃÃo Ãnica (semelparidade), apresentando alta fecundidade com cÃpulas. As paralarvas de Octopus insularis sÃo planctÃnicas, dando ao O. insularis uma alta capacidade de dispersÃo. PorÃm, estudos de biologia reprodutiva do O. insularis ainda sÃo escassos, sendo restrito basicamente a fÃmeas e as estruturas do aparelho reprodutivo e ao tamanho que esses animais atingem a maturaÃÃo e nÃo existindo nenhuma informaÃÃo sobre a complexa estrutura responsÃvel pela fertilizaÃÃo dos ovÃcitos, no caso, os espermatÃforos Esse trabalho tem como objetivo analisar a influÃncia de variÃveis ambientais na estrutura populacional e a biologia reprodutiva focada nos espermatÃforos do polvo, Octopus insularis. Para isto, serà necessÃrio analisar os parÃmetros da biologia populacional, descrever o espermatÃforo e descrever a reaÃÃo espermatofÃrica. Esta tese està dividida em trÃs capÃtulos que abordam a 1) A estrutura populacional do polvo, Octopus insularis capturado com espinhel de potes relacionado com variÃveis ambientais, que apresentou variaÃÃes de tamanho corporal significativa no perÃodo chuvoso, possivelmente relacionada ao perÃodo de reproduÃÃo e foi observado um sincronismo entre a variÃveis ambientais e o ciclo de vida destes animais. 2) A descriÃÃo morfolÃgica e anatomia funcional do espermatÃforo do polvo, Octopus insularis, que à dividido em duas estruturas a massa espermÃtica na regiÃo aboral sendo coberta pela tÃnica externa e mÃdia e o aparato ejaculatÃrio que à separado pelo liquido granular e o aparato à recoberto pela tÃnica interna e membrana interna, protegendo o filamento espiral. 3) A reaÃÃo espermatofÃrica in vitro do polvo, Octopus insularis que dura cerca de 15 minutos à iniciada com a evaginaÃÃo do aparato ejaculatÃrio e consequente lanÃamento da massa espermÃtica no meio.
|
6 |
Methods for protein analysis by capillary electrophoresis and mass spectrometryRomson, Joakim January 2018 (has links)
Protein analysis is important to understanding biological systems, but sample diversity necessitates a multitude of analysis techniques and methods. Challenges that are addressed include analysis of low abundance samples, fractionation to reduce sample complexity, and automation to reduce time and cost. Matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS) is an important technique for protein characterization. In Paper I, the sensitivity of MALDI-MS was enhanced through the fabrication of a hydrophobic coating for the MALDI target plate, yielding analyte concentration. The plate outperformed a commercial concentration plate. Capillary electrophoresis (CE) separation offers low sample consumption and high efficiency, and in Paper II, offline CE-MALDI-MS fractionation was employed. A robot system for automation was constructed and used in analysis of spermatophore proteins from the butterfly Pieris napi. The robot was also used in automated on-target trypsin digestion under a lid of liquid fluorocarbons, a simpler and cheaper alternative to controlled humidity chambers. An indication of indigenous proteolysis of the sample was seen. Electrospray ionization (ESI) is the other technique for protein analysis in MS. In Paper III, the biomarker protein osteopontin (OPN) was analyzed by ESI-MS in order to find suitable conditions for its detection. A preliminary optimization of solvents and ionization conditions was done, and tandem MS (MSn) performed to increase the reliability of identification. / Proteinanalys är viktigt för att förstå biologiska system, men mångfalden av prov kräver en mängd olika analystekniker och metoder. Utmaningar som tas upp inkluderar analys av små provmängder, fraktionering för att minska provkomplexiteten, och automatisering för att minska tidsåtgång och kostnad. Matris-assisterad laserjoniserings-masspektrometri (MALDI-MS) är en viktig teknik för proteinkarakterisering. I Artikel I förbättrades känsligheten i MALDI-MS genom tillverkning av en hydrofob beläggning på MALDI-provplattan, vilket gav en koncentration av provet. Provplattan gav bättre resultat än en kommersiell koncentrationsprovplatta. Kapillärelektroforesseparation (CE) har låg provåtgång och hög separationseffektivitet och i Artikel II användes offline CE-MALDI-MS-fraktionering. Ett robotsystem för automatisering konstruerades och användes för analys av spermatoforproteiner från fjärilen Pieris napi. Roboten användes även i automatiserad trypsinklyvning under en yta av en flytande fluorkolförening, ett billigare alternativ tilli nkubationskammare med kontrollerad luftfuktighet. En indikation på naturlig enzymatisk proteinklyvning i provet hittades. Elektrospray jonisering (ESI) är den andra tekniken för proteinanalys i MS. I Artikel III analyserades biomarkören osteopontin (OPN) med ESI-MS för att hitta lämpliga förhållanden för dess detektion. En preliminär optimering av lösningsmedel och jonisationsförhållanden gjordes, och tandem-MS (MSn) utfördes för att öka identifikationens tillförlitlighet. / <p>Full text will not be uploaded due to unpublished results. QC 20181121</p>
|
7 |
Nutrient Effects on Sexual Selection and Comparison of Mating Calls in Katydids (Tettigoniidae)Trozzo, Lara Rae 19 April 2013 (has links)
No description available.
|
Page generated in 0.0426 seconds