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Dispersion of freshwater gastropods
Buďová, Jana ; Černý, Martin (advisor) ; Juřičková, Lucie (referee)
Freshwater gastropods (Mollusca: Gastropoda) belong to two tradional taxonomic groups: prosobranchs (Prosobranchia) and pulmonates (Pulmonata). Most of these molluscs are characterized by low vagility. Therefore they usually rely on passive dispersal. Their dispersal vectors are mostly birds and water. Animals can transport snails both externally and internally. Direct methods (capture.mark.recapture, radio - tracking) and genetic methods could be used to study dispersal. For genetic studies can be used many type of molecular markers, but the recently most popular are microsatellites. According to recent studies, the dispersal of freshwater gastropods is probably not as frequent and wide - spread as assumed before. Key words: freshwater snails, dispersal, dispersal vectors, capture - mark - recapture, molecular markers, population genetics
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Population Structure of African Populations Inferred from Alu Insertions.
Fajkošová, Zuzana ; Černý, Viktor (advisor) ; Frynta, Daniel (referee)
The population genetic study was carried out on 188 unrelated individuals from 5 populations of the Sahel. Relationships of nomadic Fulani to sedentary populations of different linguistic backgrounds and geographic origins were inferred from 16 polymorphic Alu insertions. Bayesian clustering approaches could be applied due to biallelic multilocus nature of the data. Fulani were shown to be divergent from neighbouring sedentary populations (Kassena and Mossi) and similar to Somali of East Africa. In context of already published genetic data, these results could be interpreted as Saharan origin of Fulani diaspora that was caused by Sahara drying out around 6 000 BP. After this initial migration of nomads to West Africa, a primarily female gene flow (integration of females) must have influenced the Fulani population. In contrast to Fulani, Songhai have shown a signal of recent admixture in concordance with historical and linguistic assumptions. KEY WORDS Alu insertions, Fulani, population genetics, Sahel
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Nesting behaviour and population genetics of solitary bees (Hymenoptera: Anthophila)
Černá, Kateřina ; Straka, Jakub (advisor) ; Žďárek, Jan (referee) ; Paxton, Robert J. (referee)
My thesis is focused on nesting behaviour and population genetics of solitary bees. These two topics, although seemingly unrelated, bring much new information and thus contribute to the better understanding of solitary bee biology that is still insufficiently known. Although the solitary behaviour represents the necessary original state for the evolution of higher sociality or obligate cleptoparasitism, its role is largely unappreciated. Furthermore, intraspecific cleptoparasitism, which is an alternative and facultative nesting strategy in bees, is a probable antecedent state of obligate cleptoparasitism. Although the obligate cleptoparasitism is a very common strategy in solitary bees, the information about the frequency and the occurrence of intraspecific cleptoparasitism in solitary bees is rare. We studied the nesting behaviour of solitary bees to detect different behavioural patterns that could serve as preadaptations to sociality or cleptoparasitic behaviour and we also focused on the detection and description of intraspecific cleptoparasitism in solitary bees. We chose four model solitary species for these studies - Andrena vaga (Andrenidae), Anthophora plumipes (Apidae), Colletes cunnicularius (Colletidae) and Osmia rufa (Megachilidae). We described the behaviour of Andrena vaga at the...
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Implemenation of the RAD sequencing methods to the population genetic studies of hedgehogs from the genus Erinaceus
Loudová, Miroslava ; Černá Bolfíková, Barbora (advisor) ; Choleva, Lukáš (referee)
Hedgehogs from the genus Erinaceus are an important model organism for studying the postglacial recolonisation of Europe and the processes that take place in the secondary contact zones of their areas of distribution. In this study, five individuals of white-breasted hedgehog (Erinaceus roumanicus), four individuals of western hedgehog (Erinaceus europaeus) and one estimated hybrid were analysed. Geographical distribution of individuals used in the study covers the region of the Central Europe, however in the further research expansion of analsysed individuals will be needed and the whole Palearct should be sampled. The main goal was to implement novel methods in research of hedgehogs, which will enable to map the population-genomic structure of the genus Erinaceus in western Palearct. The method RADSeq (Restriction site associated DNA sequencing) enables to obtain polymorphic markers, e.g., SNPs which we used (Single Nucleotide Polymorphisms) across the genome. In this work it was analyzed 16382 SNPs. Using the binary data which indicates the presence and absence of SNPs for each species, hypotheses raised under classical analyzes of genetic markers from previous studies have not been fully confirmed. In further research it will be necessary to verify possible occurrence of biases connected with...
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Genetic structure of mammalian invasive populations on islands
Loudová, Miroslava ; Černá Bolfíková, Barbora (advisor) ; Hájková, Petra (referee)
Biological invasion is understood as introduction, establishment and expansion of organisms into new, non-native area. This is a natural process that is significantly compounded by human activities and is one of the factors that threaten biological diversity and stability of natural ecosystems. Understanding to the evolution and current status of invasive populations is especially important for planning a project to eradicate invasive species from certain areas to avoid their negative impact on the environment. One option for the research of the invasive populations and their history is the analysis of genetic material. This thesis summarizes the current knowledge on invasive populations of small mammals on the islands, with the focus on genetic studies. Specifically, the study of Norway rats (Rattus norvegicus) on Moturemu island and five archipelagos off the coast of Brittany; black rats (Rattus rattus) on Congo Cay, Madagascar, Guadeloupe Archipelago, Sainte Anne Archipelago and Canary Islands; Pacific rats (Rattus exulans) on Tetiaroa Atoll; house mice (Mus musculus) on Marion Island; house mice (Mus musculus domesticus) on Kerguelen Archipelago; red squirrels (Sciurus vulgaris) on Jersey island, West European hedgehogs (Erinaceus europaeus) in New Zealand; pygmy shrews (Sorex minutus) in Ireland and...
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Reintroduction of butterflies (Lepidoptera)
Štochlová, Tereza ; Sedláček, Ondřej (advisor) ; Straka, Jakub (referee)
The thesis deals with one of the active means of conservation - reintroduction. By this ap- proach, organisms are released in their historical range from which they have disappeared. Re- introductions typically concern vertebrates, that is, however, why this thesis focuses on a group of invertebrates - butterflies (Rhopalocera). The main aim of this work is to carry out a research of previous experiments, evaluate used methods and discover the best way to proceed with reintroduction of butterflies. This process contains many important steps. Firstly, a suitable species must be chosen, that means one that is declining and has limited dispersal abilities. Secondly, an appropriate habitat for releasing organisms must be found - host plants ought to be sufficiently abundant and the area big enough. If the habitat quality is not satisfactory, it can be achieved through management, most commonly by planting host plants, mowing or grazing. Next step is choosing the right donor population. It should be stable, genetically variable, and genetically and ecologically related to the original extinct population. After transfer and release of sufficient number of organisms, it is crucial to carry out a long-term monitoring of the newly formed population and to modify its management when necessary. All methods...
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Inffering the demographic history of populations from genomic data
Simandlová, Sára ; Reifová, Radka (advisor) ; Černá Bolfíková, Barbora (referee)
Currently, it is not difficult to obtain genomic data even from non-model organisms. These data can give us information about the demographic history of populations. Many statistical inference procedures have been developed to infer the demographic history of populations from genomic data, and I describe them in this thesis. In the introduction, I introduce the reader to important concepts in the analysis of the demographic history of populations. I then describe the different types of genomic data that can be used to infer the demographic history of populations. I then present the flow of an experiment in inferring the demographic history of populations, where I elaborate on the steps and present the approaches and methods that are used today. I provide a basic overview of the theory and logic behind each approach. I also introduce the reader the most commonly used software packages for inferring demographic histories of populations and provide a comparison between them.
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Allopatric evolution in rousettine fruit bats: from population and landscape genetics to phylogeography
Stříbná, Tereza
Population structure, biogeography and phylogenetic relationships of the fruit bat genus Rousettus have been studied in Africa and adjacent regions. The current population patterns of rousettine fruit bats in the Old World are influenced by several environmental attributes, namely the topography, climate and land cover. These variables are mirrored in fruit bat plesiomorphies related to the ecological niche of tropical flying frugivore, as well as apomorphies of rousettines including echolocation ability, roosting in caves and dispersal capacity in open landscapes with discontinuous tree cover. Phylogenetic relationships among species and subspecies of the genus have been indicated and confronted with the existing colonization scenarios. Insular populations (including habitat islands within desert oases) show frequent genetic differentiation from their mainland relatives suggesting successful founder events after traversing stretches of unsuitable habitats. Genetic differentiation evolving in less distant islands suggests involving behavioural mechanisms maintaining cohesion of isolated demes as site fidelity and natal habitat-biased dispersal. In sub-Saharan mainland Africa within the large range reaching from the southern border of Sahara to Cape Peninsula, Rousettus populations share a...
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Inferring the demographic history of populations from genomic data
Simandlová, Sára ; Reifová, Radka (advisor) ; Černá Bolfíková, Barbora (referee)
Currently, it is not difficult to obtain genomic data even from non-model organisms. These data can give us information about the demographic history of populations. Many statistical inference methods have been developed to infer the demographic history of populations from genomic data, which I describe in this bachelor thesis. At first, I introduce the reader to important concepts in analyzing the demographic history of populations. I then describe the different types of genomic data that can be used to infer the demographic history of populations. Next, I discuss statistical methods, which include methods based on site frequency spectrum data, methods using approximate Bayesian computation, methods for determining identity, and sequential Markov coalescent methods. I provide a basic overview of the theory and logic of each approach. I then present procedures for selecting inference methods. Keywords: population genetics, demographic inference, statistical inference, whole genome data
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Allopatric evolution in rousettine fruit bats: from population and landscape genetics to phylogeography
Stříbná, Tereza ; Hulva, Pavel (advisor) ; Bryja, Josef (referee) ; Vallo, Peter (referee)
Population structure, biogeography and phylogenetic relationships of the fruit bat genus Rousettus have been studied in Africa and adjacent regions. The current population patterns of rousettine fruit bats in the Old World are influenced by several environmental attributes, namely the topography, climate and land cover. These variables are mirrored in fruit bat plesiomorphies related to the ecological niche of tropical flying frugivore, as well as apomorphies of rousettines including echolocation ability, roosting in caves and dispersal capacity in open landscapes with discontinuous tree cover. Phylogenetic relationships among species and subspecies of the genus have been indicated and confronted with the existing colonization scenarios. Insular populations (including habitat islands within desert oases) show frequent genetic differentiation from their mainland relatives suggesting successful founder events after traversing stretches of unsuitable habitats. Genetic differentiation evolving in less distant islands suggests involving behavioural mechanisms maintaining cohesion of isolated demes as site fidelity and natal habitat-biased dispersal. In sub-Saharan mainland Africa within the large range reaching from the southern border of Sahara to Cape Peninsula, Rousettus populations share a...
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