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The role of individual traits in the Northern Lapwing (Vanellus vanellus) females on breeding performance, mating status and male incubation effort
Sládeček, Martin ; Šálek, Miroslav (advisor) ; Fuchs, Roman (referee)
Feather ornaments and its role as a signals in sexual selection has been broadly studied topic in avian biology. However, vast majority of studies focus especially on role of male ornamentation and female preferences in sexual selection. Despite this fact, recent work shows, that similar palette of adaptive functions can be found for female feather ornaments, and male preferences for them, respectively. This study focuses on possible importance of female melanin-based ornaments and other individual on breeding performance in the Northern Lapwing (Vanellus vanellus), common polygynous wader breeding in agricultural landscape. No significant predictor of female investment to egg size was found. Long winged females with bigger proportion of secondaries changed during prenuptial moulting and bigger extent of melanin ornaments tended, surprisingly, to later timing of breeding. Contrary to this trend, extent of female ornamentation seems to be sexually selected trait by males. Analysis of male incubation behavior shows, that males incubate more in nests of more ornamented females, as well as in nests in later incubation stage. These findings seems to be in a good agreement with "Differential allocation hypothesis". On the other site, no effect of clutch egg sizes and timing of breeding was found....
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Macroecology and macroevolution of birdsong
Mikula, Peter ; Albrecht, Tomáš (advisor) ; Osiejuk, Tomasz S. (referee) ; Šálek, Miroslav (referee)
Birdsong is one of the most astounding natural sounds which profoundly shaped our evolutionary thinking since the 19th century. Despite a strong interest in birdsong for over 100 years, our understanding of birdsong ecology and evolution over large spatial and phylogenetic scales is still very fragmentary. Answering many basic questions requires a global synthesis covering vast diversity of extant bird species and adoption of multidisciplinary approaches. In presented dissertation thesis, my co-workers and I have explored important patterns in macroecology and macroevolution of song in passerines (Order: Passeriformes), the most diverse and widespread bird order. We have focused on three key song phenomena: (1) song complexity, (2) song frequency and (3) the presence of song in female birds. We have exploited birdsong "big data" available on public citizen science databases and other open sources in order to fill several important gaps in the current knowledge. These data were analysed by a combination of phylogenetically-informed cross-species analyses and spatial macroecological approaches. Since the publication of Darwin's seminal work, elaborated songs are generally agreed to be the result of sexual selection. We developed a simple but reliable song complexity metric to explore a global diversity in...
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Foraging and reproductive strategies of selected passerine birds
Kryštofková, Milena ; Exnerová, Alice (advisor) ; Sedláček, František (referee) ; Šálek, Miroslav (referee)
According to currently generally accepted model of evolutionary optimalization of parental investments, parental behavior should be balanced to bring the highest benefits (maximal expected value of progeny) with the lowest costs invested. This necessity establishes the pressure, which forces the organisms to balance their life-history strategies according to the changing environment. More than one solution frequently exists, and it may be crucial, which one is chosen in a given circumstances. This Ph.D. thesis deals with three passerine species and investigates their foraging, reproductive and antipredatory strategies, in the framework of "costs and benefits" theory of parental decisions and also in association with the phenomenon of synurbization. The paper by Kryštofková et al. (2006) "Parental foraging strategies and feeding of nestlings in Common Redstart Phoenicurus phoenicurus" inquires whether such factors as age of nestlings, their number, or sex of parents have influence on parental feeding frequency and foraging strategies (parameters of hunting in space and time); the literary data are controversial, even for one and the same passerine species. The male uses passive foraging mode more than female and as the nestlings grow older, the proportion of passive foraging mode is increasing, while...
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Macroecology and macroevolution of birdsong
Mikula, Peter ; Albrecht, Tomáš (advisor) ; Osiejuk, Tomasz S. (referee) ; Šálek, Miroslav (referee)
Birdsong is one of the most astounding natural sounds which profoundly shaped our evolutionary thinking since the 19th century. Despite a strong interest in birdsong for over 100 years, our understanding of birdsong ecology and evolution over large spatial and phylogenetic scales is still very fragmentary. Answering many basic questions requires a global synthesis covering vast diversity of extant bird species and adoption of multidisciplinary approaches. In presented dissertation thesis, my co-workers and I have explored important patterns in macroecology and macroevolution of song in passerines (Order: Passeriformes), the most diverse and widespread bird order. We have focused on three key song phenomena: (1) song complexity, (2) song frequency and (3) the presence of song in female birds. We have exploited birdsong "big data" available on public citizen science databases and other open sources in order to fill several important gaps in the current knowledge. These data were analysed by a combination of phylogenetically-informed cross-species analyses and spatial macroecological approaches. Since the publication of Darwin's seminal work, elaborated songs are generally agreed to be the result of sexual selection. We developed a simple but reliable song complexity metric to explore a global diversity in...
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Influence of external conditions on egg incubation in lapwings (genus Vanellus) in temperate and subtropical climate
Pešková, Lucie ; Šálek, Miroslav (advisor) ; Hořák, David (referee)
During incubation, most birds require the presence of at least one parent to ensure suitable incubation conditions for embryo development. The main factors that affect the development of the embryo are temperature, humidity and egg turning. In this work, incubation conditions were investigated in two biparental Lapwing species (genus Vanellus), the Northern Lapwing (Vanellus vanellus), which faces the risk of egg cooling in temperate areas, and the Red-wattled Lapwing (Vanellus indicus), which faces the risk of egg overheating in the subtropics. A laboratory experiment testing the thermal properties of the Red-wattled Lapwing nest lining showed that it selects lining material that slows down temperature growth during egg heating, thus ensuring suitable thermal conditions during parental absence at high ambient temperatures. Temperature and egg turning during incubation were recorded by an artificial egg with a built-in sensors placed in the nests of both target species; data collected by the sensors were stored by a base-station located nearby. The average egg temperature was 32.5 řC for the Northern Lapwing, and 35.0 řC for the Red-wattled Lapwing. Egg temperature in both species fluctuated significantly, affected by many factors. Egg temperature increased with increasing ambient temperature, it...
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Significance of predation for breeding ecology and conservation in shorebirds
Kubelka, Vojtěch ; Šálek, Miroslav (advisor) ; Albrecht, Tomáš (referee) ; Hötker, Hermann (referee)
Predation is the most common cause of reproduction failure and it strongly influences breeding performance in birds, impacting the whole species population dynamics as well as it represents a major force in the evolution of avian life-history strategies. Investigating the factors driving predation rates, or quantifying predation consequences, is highly relevant for evolutionary ecology as well as for species conservation, especially in a rapidly changing world. In this dissertation, I investigate links between nest and chick predation, environmental factors, life-history and anti-predatory strategies, together with consequences for population dynamics and conservation. I use shorebirds as a uniquely suitable model system for three reasons: i) they are globally distributed; ii) have predominant ground nesting strategy and high interspecific similarity in nest appearance to potential predators; iii) are sufficiently well- studied in terms of nest predation all over the world. In the two first sections of this dissertation, Predation in the agricultural landscape and Interspecific interactions and anti-predatory strategies, Chapter 2 supports the thermoregulatory hypothesis of nest lining size rather than anti-predatory adaptation. Chapter 3 discusses, from the perspective of predation, the twofold...
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Bird population trends in Eastern Europe
Fesenko, Valeriia ; Reif, Jiří (advisor) ; Šálek, Miroslav (referee)
Recently there are many studies that show differences in the development of the bird populations all over the Europe. Most of these findings are based on the data from the western countries in which is only a smaller portion of the population of the examined species. Eastern European countries are considered to be the centre of the European biodiversity, birds included. The objective of the thesis is to, using the form of recherche, describe the development of bird populations in the Eastern Europe and to compare it with the states in the Western Europe. It was found out that the trends of the numbers of birds, agricultural and forest landscapes in the Eastern Europe were less negative than it the Western Europe. At wetlands and water birds the differences in various regions and also more stable trends were observed in the Eastern Europe compared to the countries in the Western Europe.
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Condition dependence of sexually selected ornaments in birds
Tomášek, Oldřich ; Albrecht, Tomáš (advisor) ; Verhulst, Simon (referee) ; Šálek, Miroslav (referee)
Sexual ornaments important for mating success in many species are often assumed to evolve as condition-dependent signals of individual quality. Ornament expression can be associated with age and survival, thereby signalling individual viability. Here, we have tested viability signalling function of tail streamers and their importance for within-pair and extra-pair fertilisation success in the European barn swallow (Hirundo rustica rustica). In contrast to previous studies on this subspecies, our data suggest that tail length is not associated with fertilisation success in our population. Instead, the most important predictors of within-pair and extra-pair fertilisation success were female and male age, respectively. Our data supported viability signalling function of male tail streamers, as documented by age-related within- individual increase in their length. There was no evidence for senescence in this trait. Contrary to some previous studies, the viability signalling function of tail streamers was further supported by observed selective disappearance of males with shorter tails. Several physiological mechanisms have been proposed as maintaining signalling honesty. Among them, oxidative stress from highly reactive species (RS), including free radicals, attracted a considerable attention. Given...
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