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Ornament expression and lifetime reproductive success in male barn swallows (Hirundo rustica)
Wnuková, Lucie ; Albrecht, Tomáš (advisor) ; Klvaňová, Alena (referee)
Within a lifetime of an individual, there are changes in the organism leading to an an impairment of phenotype, survival and reproduction. The expression of phenotypic traits often increases with age. Higher expression of these traits in the young age can lead to decreased probability of survival till the next season, influencing reproductive success of an individual. That is why organisms are challenged with trade-offs, when they have to allocate their limited resources either into the reproduction in form of expression of extravagant sex ornaments or into the life span. If the ornament evolved as a handicap, its exaggerated size could reduce viability of low quality individuals. Therefore, the ornament becomes a predictor of quality of its bearer and its size indicates the ability to survive till the next season. Both sexual ornamentation and inter-individual variation in life span may result in differences in reproductive success (fitness) and targeted by sexual or natural selection. Variability in reproductive success, mainly in monogamous species, can be increased also by sexual promiscuity and extra-pair mating and extra-pair copulations. This strategy can increase the opportunity for selection of traits that play role in choosing of extra-pair mate. In this work, I focused on two potential...
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Ornament expression and lifetime reproductive success in male barn swallows (Hirundo rustica)
Wnuková, Lucie ; Albrecht, Tomáš (advisor) ; Klvaňová, Alena (referee)
Within a lifetime of an individual, there are changes in the organism leading to an an impairment of phenotype, survival and reproduction. The expression of phenotypic traits often increases with age. Higher expression of these traits in the young age can lead to decreased probability of survival till the next season, influencing reproductive success of an individual. That is why organisms are challenged with trade-offs, when they have to allocate their limited resources either into the reproduction in form of expression of extravagant sex ornaments or into the life span. If the ornament evolved as a handicap, its exaggerated size could reduce viability of low quality individuals. Therefore, the ornament becomes a predictor of quality of its bearer and its size indicates the ability to survive till the next season. Both sexual ornamentation and inter-individual variation in life span may result in differences in reproductive success (fitness) and targeted by sexual or natural selection. Variability in reproductive success, mainly in monogamous species, can be increased also by sexual promiscuity and extra-pair mating and extra-pair copulations. This strategy can increase the opportunity for selection of traits that play role in choosing of extra-pair mate. In this work, I focused on two potential...
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Secondary sexual ornaments and ectoparasites in the barn swallow (Hirundo rustica)
Wichová, Eliška ; Albrecht, Tomáš (advisor) ; Sedláček, Ondřej (referee)
Parasites could represent an important evolutionary driver and play an important role in a sexual selection. In the mate selection process, females use secondary sexual ornaments, which may reflect the parasite load and health condition of males. Females would benefit from choosing males with the most extravagant sexual characters, which indicate low levels of parasite infestation. A popular model species for sexual selection study is the barn swallow (Hirundo rustica). However there are no recent studies investigating the relationship between the level of the ectoparasitic infestation and the ornamentation of the barn swallow. Results of this thesis, based on analysis of ectoparasite load in 204 individuals show, that the level of infestation by feather mites is positively correlated with outermost tail feathers and the intensity of feather holes is negatively correlated with a breast coloration. The relationship between the abundance of ectoparasites and white tail spots was not found. The effect of ectoparasites on the survival of individuals or the nest initiation date was not observed. A possitive relationship between the individual seasonal change in feather mites infestation and brood size was detected. This implies a potential trade-off between the investments into parental care and defence...
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Avian malaria in the Swallow
Krausová, Simona ; Munclinger, Pavel (advisor) ; Votýpka, Jan (referee)
Long-distance migratory birds can encounter a wide range of parasites. Various populations of birds within one species use different migration routes and can also winter in different places. It can be supposed that birds which use different migration routes should be infected with different parasites. To study the relationship between the migration and the distribution of parasites we chose the worldwide species barn swallow (Hirundo rustica) and the avian malaria parasites. Swallows migrate long distances in different migrating routes. Some populations of swallows do not migrate, they are resident. This is the reason why swallow is a good model species for finding the answers to questions whether the populations using different migration routes are infected with different parasites or not and whether or not the diversity of parasites is wider in populations which migrate long distances in comparison with the resident populations. The malaria lineages of the genus Plasmodium and Haemoproteus were detected using nested PCR and sequencing. 1242 samples from 8 different localities from the USA, Europe and Asia were tested. We detected 24 different malaria lineages. Within the genus Plasmodium 4 of 16 lines were detected for the first time and in the genus Haemoproteus 3 of 6 lines were detected for the first...
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Application of Haematological Methods in Zoological Studies
Poplová, Jitka ; Vinkler, Michal (advisor) ; Krulová, Magdaléna (referee)
Haematological methods are widely used in zoological researches. Unfortunately, especially in ecological studies there is often much imperfection in techniques adopted, and misinterpretation of results is also common. This is particularly the case of methods serving to assessment of the peripheral blood cellular composition. In this thesis I therefore decided to describe basic haematological methods, their mechanisms, advantages and disadvantages. I also highlighted possible application potential in several less widely utilised haematological techniques. In the practical part of this thesis I have shown that the examination of immature erythrocyte differential count may serve as a meaningful indicator of health state in birds.
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