National Repository of Grey Literature 37 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
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...
Phylogeography and adaptive evolution of the grey wolf
Veselovská, Lenka ; Hulva, Pavel (advisor) ; Fornůsková, Alena (referee)
Grey wolf is a highly mobile top predator, a keystone and umbrella species within ecosystems throughout the Holarctic area. The occurrence of wolves' populations is influenced by glacial history, environmental conditions and human activity. Nowadays, wolves are returning to a man-altered country where they were exterminated, and they are adapting to human dominated landscape. People have largely contributed to its extinction in many areas around the world, resulting in a decline in genetic diversity. Due to different demographic and environmental conditions, many different lineages have evolved, which can be distinguished based on morphological and genetic analyses. Climatic factors can result in the formation of ecotypes, which become heritable and genetically distinguishable. The aim of this thesis is to provide a comprehensive overview of the phylogeography and adaptive evolution of the grey wolf in the context of genetic, geographical and morphological combination data. Keywords: grey wolf, Canis lupus, phylogeography, ecotypes, adaptive evolution
Genetic consequences of bottlenecks and population admixture in Eurasian beaver (Castor fiber)
Náhlovský, Jan ; Munclinger, Pavel (advisor) ; Hulva, Pavel (referee)
In the last few centuries beavers passed through dramatic declining of the population size followed by expansion supported by reintroductions. The genetical variability is much decreased due to this bottleneck. Current beavers possess 31 known recent mitochondrial haplotypes, among which some were described independently several times. The haplotypes form two clusters, which serve as a base for dividing beaver populations into the west and east ESU. While microsatellite loci show moderate variability, the diversity of Y chromosome loci is very low. There are only ten described alleles of the DRB second exon, which belong to the MHC loci. No mitochondrial haplotype or MHC allele is shared between relict populations. This is not noticeable in samples from the time before the bottleneck. Described subspecies are therefore only the artefact of the recent bottleneck. Newly established populations comprise in many cases beavers of various origin and are more or less admixed. It seems, that the admixed populations have higher viability and conversely in some relict populations it is possible to find the evidence of the inbreeding depression. Thus, for reintroductions it is advantageous to use individuals from several source relict populations or to use beavers from admixed populations. Several species passed...
Population trends of African mammals
Homová, Viktória ; Storch, David (advisor) ; Hulva, Pavel (referee)
The African continent is known for its rich species diversity (biodiversity). We can read about the decline in African mammal populations in various sources. The main reasons of decline include loss of habitats and animal hunting. In spite of the general idea of decline mammals, in some cases the population trend is stable or growing. The aim of my thesis is to explore and summarize what is really known about the changes in the populations of all known mammalian species over the past decades. The attention of public is mainly oriented towards large flagship species, which are very well studied and various measures are put in place to protect them, especially in protected areas. The most marked decline in the number of individuals occurs in the western part of Africa, which is probably caused by a combination of lack of financial and human resources in animal protection, a large range of biotope damage and growing bushmeat trade. Species with increasing population trends are predominantly in South Africa, where there is an improvement in the management and the protection of wildlife receives more attention. Considering small mammals, there is, in most cases, no relevant data available to help determine their population trend. The population trends of species residing in the tropical rainforests are...
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...
Genomic approaches for studying speciation
Vozárová, Zuzana ; Reifová, Radka (advisor) ; Hulva, Pavel (referee)
Technological advances in DNA sequencing along with the emergence of new informatics approaches have created new possibilities in many biological fields. In this bachelor thesis, I will focus on the informatics approaches used in speciation genomics, that is research field focused on the problematics of the origin of new species. I will introduce some statistical methods used by these approaches for parameter estimation. The four particular methods I will write about are Maximum likelihood estimation, Bayesian model, Markov chain Monte Carlo and Iterative approach. I will describe several methods used for the detection of interspecific hybrids and recent as well as historical interspecific gene flow. These methods include NewHybrids, the hybrid index, genomic and spatial clines and coalescent-based methods. The thesis demonstrates the usefulness of the connection of applied mathematics and genomics for addressing general biological issues, and speciation particularly.
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...
Lineage distribution of the Gammarus fossarum species complex (Amphipoda) across Bohemian Massif and Western Carpathians
Rutová, Tereza ; Petrusek, Adam (advisor) ; Hulva, Pavel (referee)
Amphipods are an important component of temperate permanent freshwater macrozoobenthos. They have poor dispersal abilities, lack dormant stages, and their phylogeographies often reflect old historical processes. The genus Gammarus itself includes more than 200 described species spread in the Palearctic region. Many of the taxa previously described are, in fact, diversified species complexes, which is case of our most common Gammarus (G. fossarum). We have studied their diversity on the transect across the Bohemian Massif and the Western Carpathians, which form a significant biogeographical boundary for a number of other organisms. We tested whether the border between these areas is reflected in the phylogeography of G. fossarum as a representative of permanent aquatic fauna. Analysis of two mitochondrial markers revealed the presence of eight divergent G. fossarum lineages, which also differed in the nuclear genome. All eight lineages were found in the Western Carpathians, while the Czech Massif is inhabited only by two. The microendemic areas of some lineages and the occurrence of two apparently basal lineages of this complex, which were not found in southern regions, support the hypothesis that these amphipods survived Pleistocene glacial cycles even in West Carpathian refuges. We assume that...

National Repository of Grey Literature : 37 records found   1 - 10nextend  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.