National Repository of Grey Literature 74 records found  beginprevious29 - 38nextend  jump to record: Search took 0.00 seconds. 
The effect of climatic changes on genetic build-up of populations and their role in promoting adaptive radiations
Štefková Kašparová, Eva ; Janko, Karel (advisor) ; Šabacká, Marie (referee) ; Hulva, Pavel (referee)
The Southern Ocean and its enormously cold, remote and yet the wildest continent, the Antarctic, have experienced numerous rapid climatic changes. It used to be viewed as a barren wasteland with limited knowledge of species diversity or phylogeography. Recently, all aforementioned premises are being increasingly questioned, and this thesis aims to shed light on them. Firstly, multi-locus genetic markers were used to evaluate if it is the lifestyle, benthic or pelagic, including the duration of the pelagic larval period that determines the population connectivity of particular notothenioid species. It was the adult's fish lifestyle along with the oceanographic factors that are responsible for the gene flow between localities. Secondly, is lifestyle a factor determining the extent to which Pleistocene growing grounded ice sheet affected species past population dynamics? The attention was paid to Notothenioidea fish, then to Echinoidea sea urchins, and lastly to NCBI database available antarctic marine shelf and deep-sea fauna. Our findings suggest that the last glacial maximum affected more profoundly the population size of benthic shelf species. At the same time, those living in the water column or inhabiting deep slopes had more ancient population size changes. The Antarctic terrestrial evolution...
Conservation genetics of Eurasian lynx in the Western Carpathians
Ungrová, Lenka ; Hulva, Pavel (advisor) ; Kaňuch, Peter (referee)
Robust monitoring combined with genetic analyses are important approaches to protect and manage large carnivore populations successfully. The aim of this master thesis is to analyse Eurasian lynx (Lynx lynx) population within whole Slovakia for the first time using 15 microsatellite loci. Noninvasive genetics is an effective tool for monitoring animal species with large home ranges and low population densities. Noninvasive samples including feces, hair, urine and buccal swabs were collected together with tissue samples from dead (mostly roadkill) individuals. 187 samples were collected between 2017-2019, resulting in 59 successful genotypes. Two samples were incorrectly determined in the field and excluded from further analyses since they were wildcat samples. For population genetics analyses and demography, the dataset from the "Veľké šelmy 2" project was extended with 98 genotypes in collaboration with the Institute of Vertebrate Biology CAS. Overall, 68 lynx individuals were detected in the dataset of 155 genotypes. Relatedness analysis resulted in 67 significant relationships of the first degree and 9 significant relationships of the second degree. These results suggest a high relatedness among the whole population. According to the present thesis, Slovakian lynx population has the third lowest...
Population trends of animals of different taxa and regions on the basis of the Living Planet Database
Váňová, Lenka ; Storch, David (advisor) ; Hulva, Pavel (referee)
The analysis of population trends of animals is increasingly being used not only as an indicator of population changes, but also as an indicator of biodiversity decline. Living Planet Index is one of such indicators, as it shows a proportional decline or increase of all populations by means of mean annual changes in population abundance. Since the first presentation of the index in 1998, its values have been decreasing, which was interpreted as indication of a critical state of global biodiversity. Nevertheless, there are some issues concerning the index. It is unclear to what extent is it robust, if it is not too much influenced by biased data or if it does not comprise a systematic error. This thesis focuses on four vertebrate taxa and its aim is to examine the level of data heterogeneity and their potential influence on the index. For this purpose, two parameters were defined for each population, Growth and Trend. Overall, the trends in abundances were quite balanced, some populations being decreasing, some increasing, and stable populations were also present. Despite of our expectations, the heterogeneity in the data was not large enough to have a substantial effect on the index. Analysis of trends in variously defined groups (e. g. "biomes", taxa or biogeographic realms) revealed only little...
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...
Conservation genetics of grey wolf and snow leopard: effect of landscape attributes to the population structure
Benešová, Markéta ; Hulva, Pavel (advisor) ; Kreisinger, Jakub (referee)
Landscape genetic approaches allow to study effects of landscape to population microevolution. Landscape can influence gene flow even in large carnivores with good dispersal ability. Understanding the influence of landscape to the gene flow between populations is crucial for species conservation, especially in the species with low population densities. Aim of the study was to describe genetic structure of the grey wolf (Canis lupus) and snow leopard (Panthera uncia) in selected areas and to determine the influence of the landscape features on observed structure. Non-invasive genetic samples of snow leopard from Nepal were analysed, as well as invasive and non-invasive samples of grey wolf from Central Europe. Population structure was determined a posteriori using Bayesian clustering approaches that integrate genetic and geographical data, and compared to landscape connectivity models. Population structure of snow leopards is mostly influenced by human presence and presence of frequented roads, which represent a substantial dispersal barrier. Habitat suitable for this species is greatly restricted by altitude, however, during dispersal they are able to overcome areas with higher elevation than what is optimal for them. Pronounced genetic difference was found between central European and Carpathian...
Conservation genetics of the grey wolf in Central Europe
Valentová, Kamila Anna ; Hulva, Pavel (advisor) ; Galov, Ana (referee)
Conservation genetics of the grey wolf in Czech Republic and adjacent regions is studied in the present thesis. Analyses of twenty-one microsatellite loci, one sex-determining amelogenin gene and mitochodrial control region were used to verify species determination, identify individuals and estimate relationships between them, analyse population structure and estimate demographic trends based on samples collected between 2014 and 2021. Genetic detection of red fox and dog samples incorrectly assigned to wolves illustrates the hurdles of field monitoring of grey wolf. Direct evidence for the occurrence of F1 hybrids was not found. Wolves from Bohemia showed lower values of allelic richness in comparison to the ones from Western Carpathians, probably as a consequence of recent expansion. Geographic distances between detection sites of identical individuals were relatively small or moderate in this study, suggesting regular movements of animals within their home ranges. Only two long-distance dispersal events exceeding 300 km were detected. Results of parental analysis provided evidence of pack distribution within the studied area. Most relationships were detected between wolves in the northern region of Czech Republic where the first recolonizing wolf pack in 2014 was registered. Within the studied...
Non-invasive conservation genetics of ursids
Šrutová, Jana ; Hulva, Pavel (advisor) ; Hájková, Petra (referee)
This bachelor thesis is devoted to non-invasive genetics and molecular ecology of particular species of ursids(family Ursidae). This carnivore lineage is quite diversified, particular species inhabit different environments from arctic regions to tropical rainforests and they also differ in trophic niches. As remnants of megafaunal communities that occupy important positions in ecological networks, they are often referred as keystone, umbrella and flagship species which are important in conservation biology. During the Anthropocene, the existence of particular species of Ursidae is more or less influenced by human activities or their impacts. Although nature conservation has managed to stabilize the abundance of some species, habitat loss and human- bear conflicts are becoming more frequent as a consequence of the expanding human population. The aim of the work was to review the research of population structure and demography especially using non-invasive genetic techniques in particular species with intention to implement the acquired knowledge into brown bear research in the Western Carpathians in the future. The chapter about non-invasive sampling is focused to this model species. Non-invasive genetics is important tool for research especially in large, rare, highly mobile and elusive species and...
Population genetics of Pipistrellus pipistrellus species complex hibernacula
Habalová, Kateřina ; Hulva, Pavel (advisor) ; Kaňuch, Peter (referee)
This thesis deals with two cryptic pipistrelle bat species, common pipistrelle (Pipistrellus pipistrellus) and soprano pipistrelle (Pipistrellus pygmaeus) living in sympatry in continental Europe. Although both species are abundant during summer in Europe, they spent winter in mass hibernacula and there is only limited knowledge about this period. In total, 233 individuals from four mass hibernacula were sampled in Central Europe and Romania. The species composition and population variability in winter hibernacula was examined by using the tools of population genetics (analysis of mitochondrial sequences and nuclear microsatellites). Two hibernacula with exclusive or partial mass representation of soprano pipistrelle were genetically confirmed for the first time. No cytonuclear conflict neither admixed nuclear genotype was detected, that means that early stage of hybridization between both species was not revealed. Similar genetic structure in both genetic markers indicate, that swarming and hibernating populations are substantially overlapping. Compared to the P. pygmaeus, higher genetic variability was found in P. pipistrellus populations, even though genetic variability is relatively low compared to other species. It can be caused by strong gene flow, in the case of P. pygmaeus it may be caused...
Modern technologies in population biology of a highly mobile mammal
Tkáčová, Nikola ; Hulva, Pavel (advisor) ; Apfelová, Mária (referee)
This bachelor thesis is dedicated to investigate the methods applicable to research of population biology of highly mobile mammals on the example of Eurasian lynx. Eurasian lynx (Lynx lynx) is one of the most widespread felid species. This species is considered to be a suitable model organism due to its large range which includes various ecologic, climatic and demographic conditions. Eurasian lynx fundamentally participates in shaping the entire ecosystem as an apex predator. Its return to the areas of the past occurrence has an effect on species composition there. For the effective protection of this species, it is crucial to use appropriate monitoring methods to obtain information on the distribution area, abundance and population trends. Monitoring of this animal is quite difficult due to its low population density, mainly dusk and night activity and large home-range size. On account of this knowledge hi-tech methods (e.g. GPS telemetry, camera-traps, genetic monitoring) are used. Various methods of monitoring are utilized for various study goals. Telemetry is one of the most commonly used and probably the most effective method for obtaining detailed information about biology and ecology of the species. On the other side this method is invasive and it is possible to track only limited count of...

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