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Genetic variation and contact zone of two species of Slow Worm (Anguis fragilis, A. colchicapublics
Šifrová, Helena ; Gvoždík, Václav (advisor) ; Hulva, Pavel (referee)
The members of the genus Anguis are widely but hidden living reptile species in the Czech and Slovak Republic. Due to their slight morphological characters among species of the genus, presence of two out of five species in the study area has only recently been confirmed. However, a detailed knowledge about their distribution, contact zones or potential hybridization is still unknown or very insufficient. In this master thesis, 407 individuals of Anguis fragilis and A. colchica out of 281 locations were genotyped. 407 sequences of the mitochondrial marker ND2, 170 sequences of PRLR and 156 sequences RAG1 (both nuclear markers) were used for the genetic analyses. The results confirmed the dominant species A. fragilis for the Czech Republic and A. colchica for the Slovak Republic. The contact and potential hybrid zone has north-south direction from northern Moravia and Silesia, across the Morava River valleys to the Little Carpathians and the Danubian Lowland in Slovakia. The most important information of this thesis is about potential hybridization of these species. My analyses reveal that high number of individuals in the north-south direction zone has hybrid genotype. It allowed detecting the width of the hybrid zone and more accurate genetic structure among species and populations. In addition,...
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Evolution of Olfaction in Mammals with Focus on Superorder Laurasiatheria
Vondráčková, Kamila ; Hulva, Pavel (advisor) ; Hanus, Robert (referee)
The evolution history of mammals is connected with the dominance of smell and olfactory communication, which are important sense and communication channels also in recent forms. Two systems are involved in detecting and processing the molecules of scent, the main and the accessory olfactory system. These systems distinguish different types of scents, odorants and pheromones, which are also detected by different types of receptors. Significant factors for comparison of the ability of smell between mammals are both the amount of olfactory genes and the size and complexity of olfactory structures. The main emphasis in this thesis is put on the sensory part of the olfactory system and hence there is effort to support characterization of particular taxa by genomic studies. The ability of smell, respectively amount and variation of olfactory gene repertoires has been formed during the evolution on different circumstances and the ecological adaptation played a great role. The amount and diversity of olfactory receptors vary a lot in mammals and range through anosmatic Cetaceans and microsmatic bats to macrosmatic carnivores. Present thesis is focused to the superorder Laurasiatheria because of its extensive ecological differentiation and diversification of smell abilities (from anosmatic to macrosmatic...
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Abundance of and threats to the snow leopard in various regions of its occurrence
Valentová, Kamila ; Kindlmann, Pavel (advisor) ; Hulva, Pavel (referee)
Snow leopard (Panthera uncia) is an endangered species and its population size is steadily declining. This thesis attempts to introduce and analyse the main factors threating its survival with reference to each country of its occurrence: China, Bhutan, Nepal, Pakistan, Afghanistan, Tajikistan, Uzbekistan, Kyrgyzstan, Kazakhstan, Russia and Mongolia. To conserve the remaining snow leopard populations, it is necessary to detect its distribution in various areas. Here, recent data about its worldwide distribution are presented. Snow leopard has a very secretive lifestyle, which makes estimation of its abundance quite difficult. Therefore, I also present here an overview of methods, such as sign survey, capture-recapture, predator:prey biomass ratios, photo-capture rate and genetic analyses, used for estimation of abundance of snow leopard with reference to conducted studies. I discuss their advantages and disadvantages under different conditions. Key words: snow leopard, abundance, threats, worldwide distribution, conservation
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Island evolution in bats
Holá, Barbora ; Hulva, Pavel (advisor) ; Bartonička, Tomáš (referee)
Order Chiroptera is the only mammalian taxon capable of powered flight. This key adaptation allows for high dispersion capabilities, therefore bats are often the only colonizers of remote islands. More than half of all bat species inhabit islands, and nearly a quarter of them are the islands' endemic organisms. They colonize islands around the entire world, being exempt from only very small, isolated or inhospitable islands.. Island biogeography has an extraordinary importance in many aspects of evolutionary and ecological disciplines. Because of its relative simplicity, as well as the impoverished nature of island biota, emerging interactions between island populations can be better observed compared to mainland. Species that might succumb to extinction due to competition on the mainland may survive on islands. Richness of island biota is subject to two opposing forces, colonization and extinction. A dynamic equilibrium occurs when the probability of colonization and extinction is equal, meaning the number of species is constant, but the composition of species may vary. Isolation, fragmented distribution, and the small size of island populations can lead to speciation, but can also conversely reduce genetic diversity, adaptive capabilities and ultimately cause extinction. The degree of isolation,...
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Geoinformatic applications in landscape genetics
Mráz, Jakub ; Hulva, Pavel (advisor) ; Romportl, Dušan (referee)
This Bachelor thesis shows elementary methods used in landscape genetics. Landscape genetics is a combine field of population genetics and landscape ecology. This field of study uses geoinformatic and statistic methods and methods of its mother fields. Here, the genetic methods from population genetics, will not be shown. This thesis is concern by the methods that are applied in study of the population boundaries and connectivity between populations. History and paradigm of both landscape genetics and Geoninformatic methods are also mentioned, for easier understanding of context. Lastly, most methods here are listed with Geoinformatic systems (GIS), which are computer programs, capable of using these methods and apply them on needed projects. Keywords: GIS, Landscape Genetics, Landscape Ecology, Connectivity, Least-cost path, Circuit theory
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Evolutionary apects of dog domestication and hybridization with wolf
Ptáčníková, Aneta ; Hulva, Pavel (advisor) ; Černá Bolfíková, Barbora (referee)
The domestic dog (Canis lupus familiaris) is one of the most widespread domestic animal species over the world. A lot of scientific studies are focused on explaining the process of dog domestication. However, the results of these studies vary in most cases. The conclusion about the origin of dogs is complicated due to hybridization with their ancestor, the gray wolf (Canis lupus), in ancient times and also because of some archaeological discoveries, which are difficult to identify. The origin of various adaptations during domestication process allows dogs to live alongside humans. These adaptations are related to behavior and food digestion process. Hybridization between dogs and wolves in nature is a current issue. It could threaten the genetic integrity of expanding the European wolf population.
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Genomic approach in speciation studies
Habalová, Kateřina ; Hulva, Pavel (advisor) ; Mikulíček, Peter (referee)
Speciation, adaptation and hybridization are three concepts, each one referring to different process but having a common evolutionary context. Maternal line splits into two sister lines or only one line cleaves from maternal one during speciation. However it leads to formation of new species. Adaptation and hybridization can lead to formation of new species as well. New species arise by adapting to new conditions during adaptation. Within hybridization it is a desecendant of two different lines mating amongst themselves. Most of this thesis is being addressed to these issues, the lesser part is addressed to specific examples. The chapter about next-generation sequencing methods is also included, as these methods have been used more frequently recently. Key words: speciation, adaptation, hybridization, genomics, next-generation sequencing
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The role of northern refugia in Europe phylogeograpy
Benešová, Markéta ; Hulva, Pavel (advisor) ; Janko, Karel (referee)
Changeover between glacials and interglacial period singificantly affects species distribution for hundreds thousands years. Along with the traditional conception species distribution was restricted to refugia in southern Europe during glacials, Mediterrain, from where they recolonized northern parts of ranges after deglaciation. However, according to new findings many species could have had refugia to the north from this classical refugia, in central Europe. Northern refugia were often located in proximity of mountain systems or in rock massifs. Some species are, however, so adaptable that their dispersal was continuous even during ice ages to the north from southern refugia and they were able to live in cold regions. Even cold-adapted species contract to refugia, but instead of glacials their distribution is restricted during interglacial periods. Their ranges either contract to the north of Europe or undergo altitudinal shifts. Species can have refugia also in accordance with the gradient of oceanic-continental climate. In above mentioned types of refugia, complicated demographic processed connected with decreasing population size could take place, often resulting in speciation process.
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Distribution of wildcat (Felis silvestris) in Czech Republic / geomatic modelling and ecological approach
Pospíšková, Jana ; Hulva, Pavel (advisor) ; Anděra, Miloš (referee)
Population of the European wildcat (Felis silvestris) are slowly recovering after a severe decline in the 18th century. The wildcat was a rare species already on the beginning of 19th century on the territory of Czech Republic. During the 20th century the species was considered to be extinct and the scarce records to be individuals dispersed from Carpathian or West-European population. Furthermore there was lack of evidence to this observations. With the expansion of photo monitoring methods, there comes pictures of wildcats from the Beskid Mountains, Bohemian Forest, The upper Palatine Forest and Doupov mountains. After more than 60 years there is finely a proof for the presence of wildcats in Czech Republic. To understand its space requirements and dispersion context, and to know if there is a place for wildcats to live in Czech Republic, we made a habitat model in ArcGIS. This rule-based model works with attributes like land cover type, duration of snow cover, aspect and the vertical heterogeneity of terrain. The model was applied also for Slovakia, because the evaluation data only comes from Slovakia. We found out that the occurence of wildcats in the model territory relate to broad-leaf forests, duration of snow cover (>20cm) not exceeding 50 days and the southern exposure. In Czech Republic there is...
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Bird diversity and diversification: Different processes converging to the same pattern?
Černá, Vladimíra ; Storch, David (advisor) ; Hulva, Pavel (referee)
Latitudinal diversity gradient is one of the oldest known trends in the distribution of life on the Earth. Scientists have been trying to find causes of its formation for more than two hundred years. There are several hypotheses suggested to explain this gradient. Recently, it is one of the main themes of discussion among ecologists and evolutionary biologists. By this Thesis, I will try to contribute to understanding of processes that generate the latitudinal diversity gradient. Particularly, I study if there is a relationship between ambient temperature and diversification rate. Is this relationship different for individual groups of animals? I choose birds as a model group. Specifically, these six families of birds: Accipitridae, Columbidae, Furnariidae, Picidae, Psittacidae and Strigidae. These groups include more than 1500 species. Each of them has the same universal gradient of diversity, with the highest diversity concentrated in the tropics. My objective was to find out, whether the universal gradients of bird's diversity had been shaped by the same historical processes. Or alternatively, whether different evolutionary trajectories had converged to the same gradients. The main outcome of my work is a discovery that some of the selected families diversified faster in warmer climates...
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