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Fitness costs and benefits of sexual promiscuity in birds
Zdobinská, Helena ; Michálková, Romana (advisor) ; Sládeček, Martin (referee)
In more than 75 % bird species, extra-pair paternity (situation, when at least one extra-pair young in the nest is sired by other male than a social partner of female) has been found. While male interset in attending extra-apir copulations (EPC) seems to be intuitive (more offsring sired), female motivation to engage in EPC are much less clear and obvious. Therefore, many adaptive hypotheses have been proposed to explain female proscuity. Adaptive hypothese state, that female benefits from this behaviour (higher genetic quality of offspring). The empirical evidence for such benefits, however, are missing and adaptive hypotheses remain a controversial topic. This has led to the emergence of non-adaptive hypothesis, that assume that EPC can evolve as a by-product of selection on other trait and female may not benefit from this behaviour. However, non-adaptive hypotheses are often neglected. Aim of this bachelor thesis is to take into account benefits and costs for both sexes and to point out some of the limitations of studies on EPC. Key words: Extra-pair paternity, extra-pair copulations, promiscuity, adaptive hypothesis, nonadaptive hypothesis, sexual selection, limitation of studies
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Evidence for direct and indirect benefits of female promiscuity in vertebrates
Kuba, Martin ; Albrecht, Tomáš (advisor) ; Šulc, Michal (referee)
Female promiscuous behaviour has been observed in many vertebrate groups but its evolution and potential benefits to promiscuous females remain unclear. To explain female promiscuous behaviour, both adaptive and non-adaptive hypotheses have been proposed. According to adaptive hypotheses, females are promiscuous, because they gain benefits through multiple male copulations. These can further be divided into direct benefits hypotheses, where females are assumed to benefit directly from promiscuity by gaining more resources to themselves and improving their own survival, and indirect (genetic) benefits hypotheses where fitness gains to promiscuous females are through improved quality of their offspring. In contrast, according to non-adaptive hypotheses, females do not gain any benefits from promiscuous behaviour and female promiscuous behaviour is a result of male offensive strategies to gain paternity. Adaptive hypotheses, especially those concerning genetic benefits, are highly debated and existing studies often differ in their conclusions. The aim of this thesis is to provide a review of studies evaluating adaptive and non-adaptive hypotheses to explain female promiscuous behaviour in vertebrates. Key words: Promiscuity, sexual conflict, sperm competition, good genes, genetic complementarity,...
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Fitness costs and benefits of sexual promiscuity in birds
Zdobinská, Helena ; Michálková, Romana (advisor) ; Sládeček, Martin (referee)
In more than 75 % bird species, extra-pair paternity (situation, when at least one extra-pair young in the nest is sired by other male than a social partner of female) has been found. While male interset in attending extra-apir copulations (EPC) seems to be intuitive (more offsring sired), female motivation to engage in EPC are much less clear and obvious. Therefore, many adaptive hypotheses have been proposed to explain female proscuity. Adaptive hypothese state, that female benefits from this behaviour (higher genetic quality of offspring). The empirical evidence for such benefits, however, are missing and adaptive hypotheses remain a controversial topic. This has led to the emergence of non-adaptive hypothesis, that assume that EPC can evolve as a by-product of selection on other trait and female may not benefit from this behaviour. However, non-adaptive hypotheses are often neglected. Aim of this bachelor thesis is to take into account benefits and costs for both sexes and to point out some of the limitations of studies on EPC. Key words: Extra-pair paternity, extra-pair copulations, promiscuity, adaptive hypothesis, nonadaptive hypothesis, sexual selection, limitation of studies
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Extrapair paternity and adaptive explanations of female promiscuity in birds
Siegelmannová, Nikola ; Albrecht, Tomáš (advisor) ; Poláková, Radka (referee)
Extra-pair paternity are commonly detected in populations of social monogamous birds, however it remains unclear how this strategy evolves and is maintained. Several adaptive and non-adaptive explanations were, proposed to explain female promiscuity with major attention being devoted to the hypothesis of genetic benefits to females in form of good or compatible genes for their offspring. These theories assume that extra-pair offspring are of better quality than their maternal half-sibs in the nest. This thesis summarizes available studies that have compared benefits and costs for males and females from extra-paired paternity and evaluated the adaptive explanation of female promiscuity. It seems that the evidence for inderect benefits to female promiscuity are generally week in birds, and other mechanisms, such as sexual conflict or genetic correlations between the sexes may play a role in explaining the female bird propensity to copulate with extra-pair mates. Powered by TCPDF (www.tcpdf.org)
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