16 research outputs found

    Two research avenues for future mate-choice copying studies: a comment on Davies et al

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    Social learning by mate‐choice copying increases dispersal and reduces local adaptation

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    In heterogeneous environments, dispersal may be hampered not only by direct costs, but also because immigrants may be locally maladapted. While maladaptation affects both sexes, this cost may be modulated in females if they express mate preferences that are either adaptive or maladaptive in the new local population. Dispersal costs under local adaptation may be mitigated if it is possible to switch to expressing traits of locally adapted residents. In a sexual selection context, immigrant females may learn to mate with locally favoured males. Mate‐choice copying is a type of social learning, where individuals, usually females, update their mating preferences after observing others mate. If it allows immigrant females to switch from maladapted to locally adapted preferences, their dispersal costs are mitigated as mate choice helps them create locally adapted offspring. To study if copying can promote the evolution of dispersal, we created an individual‐based model to simulate the coevolution of four traits: copying, dispersal, a trait relevant for local adaptation, and female preference. We contrast two scenarios with copying—either unconditional or conditional such that only dispersers copy—with a control scenario that lacks any copying. We show copying to lead to higher dispersal, especially if copying is conditionally expressed. This leads to an increase in gene flow between patches and, consequently, a decrease in local adaptation and trait‐preference correlations. While our study is phrased with female preference as the learned trait, one may generally expect social learning to mitigate dispersal costs, with consequent feedback effects on the spatial dynamics of adaptation.info:eu-repo/semantics/acceptedVersio

    Gestão do desperdício de materiais

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    Estágio realizado na ColepCCL e orientado pelo Eng.º José Carlos OliveiraTese de mestrado integrado. Engenharia Mecânica. Faculdade de Engenharia. Universidade do Porto. 200

    Mate-choice copying: A fitness-enhancing behavior that evolves by indirect selection

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    A spatially explicit, individual-based simulation model is used to study the spread of an allele for mate-choice copying (MCC) through horizontal cultural transmission when female innate preferences do or do not coevolve with a male viability-increasing trait. Evolution of MCC is unlikely when innate female preferences coevolve with the trait, as copier females cannot express a higher preference than noncopier females for high-fitness males. However, if a genetic polymorphism for innate preference persists in the population, MCC can evolve by indirect selection through hitchhiking: the copying allele hitchhikes on the male trait. MCC can be an adaptive behavior-that is, a behavior that increases a population's average fitness relative to populations without MCC-even though the copying allele itself may be neutral or mildly deleterious.info:eu-repo/semantics/publishedVersio

    The role of spatial structure in the process of mate-choice copying

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    A cópia da escolha de parceiros sexuais (que simplificarei para “cópia”) é um tipo de aprendizagem social onde a preferência sexual de um indivíduo é influenciada pela escolha sexual de conspecíficos. Esta tese explora os efeitos teóricos deste comportamento na dinâmica evolutiva das populações. Para isso exploro modelos baseados em indivíduos focando numa estrutura espacial, pois considero que muitos benefícios da cópia surgem nestas condições. A tese está dividida em seis capítulos. No capítulo 1 faço uma breve introdução ao tema e à estrutura da tese. O capítulo 2 consiste num modelo que simula a evolução da cópia numa única parcela ambiental e mostra que o comportamento pode evoluir por seleção indireta, aumentando a proporção de machos mais adaptados, aumentando a fitness da população. Porém, este efeito só ocorre quando a preferência da fêmea não coevolve com a característica do macho, algo improvável numa única parcela. No capítulo 3 simulo a evolução da cópia num ambiente heterogéneo com múltiplas parcelas. Este modelo mostra que a cópia é adaptativa para as fêmeas migrantes, permitindo a escolha de machos mais adaptados localmente. Este efeito aumenta a tendência de dispersão e diminui o grau de adaptação local, aumentando a homogeneidade entre parcelas. O capítulo 4 apresenta um modelo onde populações expandem através de um gradiente ambiental, testando se o efeito da dispersão e da adaptação local tornam a cópia menos adaptativa nestas circunstâncias. O modelo mostra que a cópia pode ser adaptativa, aumentando a velocidade de expansão, dependendo do tipo de preferências e comportamento de cópia usado. No capítulo 5 apresento uma visão crítica de duas meta-análises publicadas por outros autores recentemente, onde saliento dois caminhos para estudos empíricos no tema da cópia. Finalmente, no capítulo 6 apresento uma discussão dos resultados da tese, considerando as limitações dos estudos teóricos e perspetivas futuras.Mate-choice copying is a type of social learning whereby an individual’s mate preference is influenced by the mate choices of conspecifics. This thesis explores the theoretical effects of this behaviour on the evolutionary dynamics of populations. I use individual-based models and focus on spatial structure, as many benefits of copying are predicted to arise under these conditions. The thesis is divided into six chapters. In chapter 1, I give an overview of the field and of the structure of the thesis. Chapter 2 simulates the evolution of copying in a single habitat patch and shows that it can evolve though indirect selection, leading to a higher proportion of adapted males, which increases population fitness. However, this only occurs when female preference does not coevolve with the trait, which is unlikely if we consider only a single habitat. Therefore, chapter 3 simulates the evolution of copying in a heterogenous multi-patch environment with individuals moving between patches. The model shows that copying is especially adaptive to migrating females because it informs them of locally adapted males. This effect promotes greater dispersal but weakens local adaptation, increasing homogeneity between patches. Chapter 4 simulates populations expanding through an environmental gradient, to test whether these effects on dispersal and local adaptation make mate-choice copying less adaptive under these circumstances. The model shows that copying can still be adaptive, increasing the speed of expansion, but depends on the type of preference rules and copying behaviours females use. Chapter 5 is a commentary on two recently published meta-analyses, where I highlight two main avenues for future empirical research. Finally, chapter 6 is a discussion of the thesis main results, of mathematical models’ limitations, and of future perspectives, where I highlight the importance of theoretical research for empirical knowledge and vice versa

    Comportamento reprodutor de rapinas diurnas em cativeiro na Coudelaria Alter Real e em Vaiamonte

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    Tese de mestrado. Biologia (Biologia da Conservação). Universidade de Lisboa, Faculdade de Ciências, 2011In this work the reproductive behavior of four couples of diurnal birds of prey, maintained in captivity in Coudelaria Alter Real and in Vaiamonte, where they are bred for falconry purposes, were studied between February and June of 2009. The main goal of the study was to compare the parental effort of the couples between two clutches and their periods of pre-incubation, incubation and chicks’ rearing, using several variables based on the frequency of visits to the nest and on the proportion of time spent in the nest. The idea was to evaluate the failure effect of the first clutch (due to natural causes or to the artificial removal of the eggs) on the birds’ productivity in the second clutch. After the failure of the first clutch, a similar or greater investment was expected in the second clutch, in order to guarantee reproductive success. The studied couples were as follows: one couple of Harris’ hawks (Parabuteo unicinctus), one couple of peregrine falcons (Falco peregrinus), one couple of saker falcons (F. cherrug) and one couple of hybrids gyr-saker falcons (F. rusticolus X F. cherrug), where the male is 75% and the female 50% gyr falcon. None of the couples studied did reproduce successfully. The causes of failure seem to have been different for every couple and independent from each other. Moreover, only the Harris’ hawks laid two clutches, with less investment in the second, contradicting our predictions. This result reflects probably the behavior of the male that reduced his effort on almost all the variables during the second clutch. The obtained results allow to infer on some techniques and breeding conditions of these birds in captivity, but they can’t be generalized without a deeper study and a greater sampling effort – few couples were observed and only one breeding season was sampled.Neste estudo foram analisados, entre Fevereiro e Junho de 2009, os comportamentos reprodutores de quatro casais de aves de rapina diurnas mantidas em cativeiro na Coudelaria Alter Real e em Vaiamonte, onde existem instalações de reprodução destas aves para a prática da falcoaria. O objectivo principal do estudo foi comparar o esforço parental dos casais entre duas posturas e seus períodos de pré-incubação, incubação e cuidados com as crias, utilizando diversas variáveis baseadas na frequência de visitas e proporção de tempo passado no ninho. A intenção era avaliar o efeito do insucesso da primeira postura (por causas naturais ou por remoção artificial de ovos) na produtividade das aves de rapina durante a segunda postura. Esperava-se que após insucesso da primeira postura os casais investissem na segunda com esforço igual ou superior ao da primeira, de modo a garantir o sucesso reprodutor. As aves estudadas foram as seguintes: um casal de búteos de Harris (Parabuteo unicinctus), um casal de falcões-peregrino (Falco peregrinus), um casal de falcões-sacre (F. cherrug) e um casal de falcões híbridos de gerifalte-sacre (F. rusticolus X F. cherrug) sendo o macho 75% falcão-gerifalte e a fêmea 50% falcão-gerifalte. Nenhum destes casais conseguiu obter sucesso reprodutor. As causas desse insucesso parecem ter sido diferentes para todos os casais e independentes umas das outras. Para além disso, apenas os búteos de Harris tiveram duas posturas, com investimento reduzido na segunda, ao contrário do esperado. Este resultado deve-se, provavelmente, ao comportamento do macho, cujo esforço parental foi menor na segunda postura em quase todas as variáveis. Os resultados obtidos permitem inferir sobre algumas técnicas e condições de reprodução das aves de rapina em cativeiro, mas não podem ser generalizados sem um estudo mais aprofundado e um esforço de amostragem maior – foram observados poucos casais e foi amostrada uma época reprodutiva apenas

    Tratamento da tuberculose latente: Revisão das normas, 2006 Treatment of latent tuberculosis infection: Update of guidelines, 2006

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    A Comissão de Trabalho de Tuberculose da Sociedade Portuguesa de Pneumologia, sentindo a necessidade de criar normas de actuação referentes à terapêutica da tuberculose latente, coordenou a elaboração de um conjunto de recomendações, com vista a uniformizar os procedimentos nesta área. Para a elaboração do presente documento, contou com a colaboração de elementos das sociedades portuguesas de Medicina Interna, de Pediatria e de Doenças Infecciosas. Procedeu-se a uma revisão e actualização das normas para o rastreio e tratamento da tuberculose latente no adulto imunocompetente e na criança, bem como em adultos e crianças infectadas pelo vírus da imunodeficiência humana. As presentes normas devem ser entendidas como linhas gerais de orientação, e a sua aplicação não deve dispensar a análise de cada caso individual.The Tuberculosis Working Group of the Portuguese Society of Pulmonology, feeling the need to develop guidelines for the diagnosis and treatment of latent tuberculosis infection, compiled a set of recommendations, in view to standardize procedures on this area. This document was prepared in collaboration with the Portuguese Societies of Internal Medicine, Pediatrics and Infectious Diseases. A review and update of guidelines for tracing and treatment of latent tuberculosis infection was made, concerning immunocompetent children and adults, as well as immunocompromised children and adults due to HIV infection. It is understood that these guidelines are to be used as general recommendations, and they should not replace the individual analysis of each case

    Social learning by mate‐choice copying increases dispersal and reduces local adaptation

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    In heterogeneous environments, dispersal may be hampered not only by direct costs, but also because immigrants may be locally maladapted. While maladaptation affects both sexes, this cost may be modulated in females if they express mate preferences that are either adaptive or maladaptive in the new local population. 2. Dispersal costs under local adaptation may be mitigated if it is possible to switch to expressing traits of locally adapted residents. In a sexual selection context, immigrant females may learn to mate with locally favoured males. Mate-choice copying is a type of social learning, where individuals, usually females, update their mating preferences after observing others mate. If it allows immigrant females to switch from maladapted to locally adapted preferences, their dispersal costs are mitigated as mate choice helps them create locally adapted offspring. 3. To study if copying can promote the evolution of dispersal, we created an individual-based model to simulate the coevolution of four traits: copying, dispersal, a trait relevant for local adaptation, and female preference. We contrast two scenarios with copying—either unconditional or conditional such that only dispersers copy—with a control scenario that lacks any copying. 4. We show copying to lead to higher dispersal, especially if copying is conditionally expressed. This leads to an increase in gene flow between patches and, consequently, a decrease in local adaptation and trait-preference correlations. 5. While our study is phrased with female preference as the learned trait, one may generally expect social learning to mitigate dispersal costs, with consequent feedback effects on the spatial dynamics of adaptation

    Tratamento da tuberculose latente: Revisão das normas, 200622 Comissão de Trabalho de Tuberculose da Sociedade Portuguesa de Pneumologia Apoio científico de: Sociedade Portuguesa de Medicina Interna, Sociedade Portuguesa de Pediatria e Sociedade Portuguesa de Doenças Infecciosas.

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    Resumo: A Comissão de Trabalho de Tuberculose da Sociedade Portuguesa de Pneumologia, sentindo a necessidade de criar normas de actuação referentes à terapêutica da tuberculose latente, coordenou a elaboração de um conjunto de recomendações, com vista a uniformizar os procedimentos nesta área. Para a elaboração do presente documento, contou com a colaboração de elementos das sociedades portuguesas de Medicina Interna, de Pediatria e de Doenças Infecciosas. Procedeu-se a uma revisão e actualização das normas para o rastreio e tratamento da tuberculose latente no adulto imunocompetente e na criança, bem como em adultos e crianças infectadas pelo vírus da imunodeficiência humana. As presentes normas devem ser entendidas como linhas gerais de orientação, e a sua aplicação não deve dispensar a análise de cada caso individual.Rev Port Pneumol 2007; XIII (3): 397-418 Abstract: The Tuberculosis Working Group of the Portuguese Society of Pulmonology, feeling the need to develop guidelines for the diagnosis and treatment of latent tuberculosis infection, compiled a set of recommendations, in view to standardize procedures on this area. This document was prepared in collaboration with the Portuguese Societies of Internal Medicine, Pediatrics and Infectious Diseases. A review and update of guidelines for tracing and treatment of latent tuberculosis infection was made, concerning immunocompetent children and adults, as well as immunocompromised children and adults due to HIV infection. It is understood that these guidelines are to be used as general recommendations, and they should not replace the individual analysis of each case.Rev Port Pneumol 2007; XIII (3): 397-418 Palavras-chave: Tuberculose latente, rastreio, quimioprofilaxia, terapêutica, Key-words:: Latent tuberculosis infection, tracing, chemoprophylaxis, treatmen
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