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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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Long term changes of song within individual passerine populations
Žabková, Michaela ; Petrusková, Tereza (advisor) ; Turčoková, Lucia (referee)
Song is a very important means of communication among passerines - it is species- specific, and they use it to communicate with other members of the same species, but also in interspecific recognition. However, the song differs not only between species but also between conspecifics or conspecific populations, both in space and time. In contrast to groups with congenital vocalisation, i.e. all other bird taxa with exception of hummingbirds and parrots, passerines learn their song during the life. In some species, i.e. open-ended learners, song can change throughout the life. Nevertheless, learning is not the only cause of the origin of spatiotemporal variability. This review is about changes in the song of the individuals as well as within the population of various species of passerines. Song variability can be caused by the changing environment in the surrounding area of the observed populations or ongoing social interaction among the individuals. The individual song stability is more common among species, that are closed-ended learners. Within populations song stability is rather rare.
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Mechanisms enabling individual recognition of passerine birds
Caha, Ondřej ; Petrusková, Tereza (advisor) ; Vokurková, Jana (referee)
Vocalization allows birds to communicate over long distances or in environments, where can be difficult to detect visual signals. Vocalization can be divided into songs and calls. Song may inform a listener of signal about species, sex, male quality, aggressive motivation and also about singer's identity. Recognition of different individuals is very valuable ability that is commonly used during territorial interactions among males. Correct identification of males, that pose different threat, enable to respond adequately to the situation and save energy or to avoid injury in potential conflict. The ability of individual distinguishing based on song was demonstrated by using playback experiments for many passerines, but it was rarely revealed the way of such identification. This review deals with the issue of neighbour-stranger experiments that confirm the ability of passerines to discriminate between neighbours and strangers. Further, it focus on structures or characteristics of birdsong enabling individual recognition of passerines and their possibly use for individual acoustic monitoring.
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Yellowhammer as a model species for studies on passerine dialects
Diblíková, Lucie ; Petrusková, Tereza (advisor) ; Procházka, Petr (referee)
Even though birdsongs and bird dialects have been subject to considerably intense scientific research, the domain of bird dialects is still worth attention of scientists. There is a large number of hypotheses about the emergence of bird dialects which separately or combined explain their origin. Dialects can be classified on the basis of the structure of a birdsong which they are related to or according to a geographical scale (micro and macrodialects). Research on bird dialects belongs to such type of studies that require great amount of data and thus large amount of time and finance is needed. Nonetheless, this obstacle can be avoided by involving general public into the research, however choosing a suitable model species is necessary. Yellowhammer (Emberiza citrinella), which was chosen in this study, is undoubtedly a convenient species for its common occurrence and distinguishable birdsong. Yellowhammer males sing during a large part of the season and their dialects can be easily recognized. Moreover, some scientists differentiate between macrodialects, that should be divided across western and eastern Europe, and could be used to make the research more attractive for general public. Till now yellowhammer dialects have been thoroughly explored in Denmark and in some parts of Germany, but in other...
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Winter teritoriality im passerines in relation to environmental and climatic conditions
Glückseligová, Pavla ; Musil, Petr (advisor) ; Reif, Jiří (referee)
This thesis is focused on winter territoriality of passerines. It summarizes general knowledge of territories, territorial behaviour and broader knowledge about winter territoriality. Winter social behaviour of individual species, their territoriality, migratory strategy and food preferences were summarized for Western Palearctic bird species. Furthermore, effect of climate change on passerines and their migratory behaviour, timing of breeding and their relationship to food abundance and conspecific competition. In the last chapter, there is discussed effect of climate change on species displaying wintering territoriality. Increasing temperature can affect food availability, competition for sources and consequently reproduction success.
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Functions of repertoire size in passerines
Kinštová, Anna ; Petrusková, Tereza (advisor) ; Musilová, Zuzana (referee)
5 Abstract Songbirds use visual and vocal signals to communicate. Visual signals have several disadvantages, for example they are more difficult to detect in darkness or poor light. On the contrary vocal signals, the most typical and advanced way of communication in passerines, can be noticeable even in these conditions. Vocalizations can be divided into songs and calls. The two main functions of a song, especially in songbirds living in temperate zone, are to defend a territory and to attract a mate. The songbirds have a considerable variety in songs among particular species. Moreover, the individual of the same species can differ greatly in their repertoire size. This means they have different number of song types or syllables. Currently we assume that repertoires have arisen in response to widespread female preference for mates with larger repertoires. The evolution of repertoire complexity was driven by a sexual selection of females preferences. In this case the repertoire size is considered to be a phenotypic trait which should work as an honest indicator of male quality. Therefore females could obtain direct and indirect benefits. I study the functions of repertoire size in passerines in my bachelor thesis. I focus in particular on possible benefits that females could gain from pairing with males with...
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