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Mechanisms of reproductive isolation between two hybridizing passerine species, the common nightingale and the thrush nightingale
Poignet, Manon ; Reifová, Radka (advisor) ; Choleva, Lukáš (referee) ; Kratochvíl, Lukáš (referee)
iv - ABSTRACT (in English) - A key step in the origin of new species is the evolution of the reproductive isolation mechanisms separating the gene pools of newly emerging species. Despite a growing number of studies, we still know very little about the molecular, physiological and genetic mechanisms underlying reproductive isolation. Hybrid zones represent useful examples of ongoing species differentiation and can provide information about the nature of reproductive isolation separating the species and mechanisms facilitating or limiting the hybridization. Using two naturally hybridizing passerine species, the common nightingale (Luscinia megarhynchos) and the thrush nightingale (L. luscinia), we evaluated several mechanisms of reproductive isolation at the chromosomal, phenotypic, and genetic levels, with a focus on postmating prezygotic (PMPZ) and postzygotic isolation mechanisms. These nightingale species diverged ~1.8 Mya and currently hybridize in a secondary contact zone running across Central and Eastern Europe. First, we analysed the genetic composition of the secondary contact zone, demonstrating that parental forms are predominant in the hybrid zone, with few F1 hybrids (3.4%), early backcross hybrids (3.1%) and the absence of F2 hybrids. This suggests strong but incomplete reproductive isolation....
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Diversity and abundance of birds in 3D space of Žofínský prales primary forest
Kučerová, Eliška ; Hořák, David (advisor) ; Korňan, Martin (referee)
Bird species are specialized in diverse types of environments. Considering for example forest species, this does not mean that all species inhabit the same ecological niches. Some species occupy undergrowth while others prefer treetops. Some birds are bound to clearings and other gaps in forest cover, and other species require old trees with cavities. Primary Central European mixed forest is not a homogenous environment. But, on small spatial scales, the environment is very heterogeneous. We get an unprecedented variety of habitats especially when including the forest vertical dimension, which birds use much more than it is usually considered in studies. This diploma thesis describes in detail the bird assemblage in the Czech oldest nature reserve NPR Žofínský prales in which vegetation research is currently in progress. However, research dealing with bird mapping in forests still rarely consider the vertical dimension of the environment. Most bird censuses focus on the diversity of species at a site but usually do not include abundance of individual species. I, therefore, focused on a detailed mapping of the bird community on a 50-hectare area in NPR Žofínský prales. During the census, each bird and each bird's exact position in the 3D space of the forest were recorded. Special attention is paid...
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Kokcidie ptáků Galapág
KORDÍKOVÁ, Lucie
This study investigates coccidian parasites of the genera Eimeria and Isospora in faecal samples of birds from the Galapagos Islands. The study determines prevalence of coccidia on individual islands and bird species. Description of recorded coccidian parasites is based on morphological features of their oocysts as well as on phylogenetic relationships.
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Střevní paraziti ptáků na Svalbardu
ŽÁNOVÁ, Veronika
The study aimed to obtain essential knowledge about the distribution of intestinal parasites of birds occurring in Svalbard. Noninvasive coprological techniques were used to detect coccidian, cryptosporidian and microspordian parasites. The research included field collection of faecal samples and laboratory examination by microscopic and molecular methods.
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Selected names of bird species and their origin in czech language.
MĚRTLOVÁ, Tereza
The diploma thesis deals with the origin and development of selected names of birds in Czech language. It studies the characteristics of the selected expressions, it compares their state in Old and New version of Czech language, including an explanation of the origin of the names on the basis of the interpretation using etymological dictionaries of the Czech language. The thesis is also focused on derived words or phrasal idioms.
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Interactions between plants, herbivorous insect and predators: mechanisms and ecological importance
MRÁZOVÁ, Anna
The thesis describes the interactions between the three trophic levels from different perspectives. It focuses on the role of plants, herbivorous insect, and invertebrate predators and birds in trophic interactions. More specifically, it describes indirectly induced plant defence and communication with higher taxa and changes in predation pressure and insect communities in response to defensive chemical compounds released from herbivory-damaged plants.
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Evolution of sperm morphology in birds
Zemanová, Aneta ; Stopka, Pavel (advisor) ; Frolíková, Michaela (referee)
The sperm is one of the most variable cells that carry various morphological differences across species and is subject to selective pressures that may drive changes in sperm morphology. Different morphological adaptations that emerged may enhance successful fertilization. This thesis focuses on the analysis of sperm morphology in different species of songbirds, the representation of proteins in both sperm and seminal fluid, and their classification into different categories of gene ontology. The main aim of my thesis was to determine whether differences in proteomes follow the level of sperm competition or rather their phylogeny. Six species of songbirds were selected for this study: Marsh Warbler (Acrocephalus palustris), White-throated dipper (Cinclus cinclus), European greenfinch (Chloris chloris), Barn swallow (Hirundo rustica), Common chiffchaff (Phylloscopus collybita) and Zebra finch (Taeniopygia guttata). Sperm morphometric measurements were made in all the species, with the greatest variability recorded in the central part of the sperm flagellum. Using mass spectrometry, were analysed sperm and seminal fluid proteins separately and discriminant analysis was performed to determine the proteins that most differentiated the selected songbird species from each other. Obtained data provide...
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Bird conservation status along a successional gradient in abandoned military areas
Bystřický, Václav ; Reif, Jiří (advisor) ; Hořák, David (referee)
Populations of open habitat bird species has significantly decreased in the Czech Republic during the last decades due to a number of negative factors, such as urbanization and intensification of agriculture. Due to the deterioration of the quality of these biotopes, a number of bird species (not only those of conservation importance) were forced to look for remaining fragments of favorable habitats, which are, for example, abandoned military training areas. The attractiveness of these territories lies primarily in their former closure for military purposes, which has protected these areas against these negative factors. In addition, army's activities created a heterogeneous landscape characterized by a mosaic of biotopes in different stages of vegetation succession - from bare ground, through grasslands, sparse scrubland, dense scrubland to the forest. However, the significance of abandoned military training areas for birds requires deeper investigation. The main goal of this thesis was to describe conservation importance of bird communities in individual biotopes along the successional gradient, for which a survey of 42 abandoned military training areas was used. The results of my work show that the most declining, endangered and protected species of birds sought out early successional habitats...
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Movements within non-breeding grounds in terrestrial migratory birds
Kadlecová, Barbora ; Brlík, Vojtěch (advisor) ; Remeš, Vladimír (referee)
In recent years, the ecology of migratory birds has been a frequently studied subject especially due to modern tracking technologies. However, facts about behaviour of migratory birds on wintering areas are still limited. This thesis gathers information about movements within non-breeding grounds and stationary behaviour of terrestrial birds on wintering areas and about reasons of the movements. The majority of described movements occurred in Africa and South America and they were usually made by insectivorous songbirds. Majority of published data describes long-distance movements above 100 km. The most discussed factor of the movements was an availability of food which is affected by vegetation and the seasonal weather. Apart from the environmental factors I considered inner factors too, e. g. age or sex of birds. I also proposed some additional factors as a potential cause of movements within non-breeding grounds. The information about movements on wintering areas could serve as ground for further research of the behaviour of birds on wintering grounds, the influence of environmental conditions on the ecology of migratory birds and the information could also improve the protection of migratory birds.
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