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Secondary male ornamentation and extra-pair paternity: experimental manipulation in collared flycatchers (Ficedula albicollis)
Šplíchalová, Petra ; Albrecht, Tomáš (advisor) ; Svobodová, Jana (referee)
Extra-pair paternity, resulting from sexual promiscuity, is frequently detected in socially monogamous passerines. Previous studies on extra-pair paternity in birds have identified several traits correlated with increased fertilization success of males. However, the effect of experimental manipulation of ornament expression on male fertilization success has only seldom been evaluated. The aim of this thesis is to reveal the potential link between the size of a trait suposedly playing a role in female mate choice decision and male fertilization success in collared flycatchers (Ficedula albicollis), using experimental manipulation of male forehead white patch size. In addition, mating success, mating speed of the manipulated and control individuals and size of a brood (a proxy for female reproductive investments) were evaluated. Results indicate that forehead patch size manipulation did not affect male social pairing success (mating speed), his social mate reproductive investments (brood size) or male extra-pair and within-pair fertilization success. Keywords: extra-pair paternity, sexual selection, reproductive success, collared flycatcher
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An intensity of plumage bacterial load and resistence against bacteria-caused feather degradation in tropical birds of Afromontane areas of Cameroon
Kyptová, Markéta ; Javůrková, Veronika (advisor) ; Adamík, Peter (referee)
Microorganisms are considered to be a significant selective factor affecting bird's life strategies. The body cover, including feather, is occupied by a wide range of bacteria that are in their host in different interactions. Group of microorganisms degradate keratins of feather is still most studied and most species of birds have them in feather. This feather degrading bacteria can disrupt the wear and its function and thus cause great losses to its fitness. Therefore, it seems likely that these feathers degrading bacteria and microorganisms generally play a significant role in creating defence mechanisms against their negative effects. One of the most important defence mechanisms to protect feathers against the action of microorganisms is the deposition of melanin pigments. This diploma thesis deals with the analysis of the total bacterial load in feathers and its resistance against bacterial degradation in 47 species of birds trapped in afromontan areas of western Cameroon. The specific aim of the thesis was to determine differences in the total number of bacteria in plumage in species with different life strategies, especially feeding and reproductive strategies. At the same time, the phtilochronological analysis of the quality of the plumage was performed and in vitro experiments were tested...
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