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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Fylogeografie rodu Squalius v Albanii / Phylogeography of the genus Squalius in Albania

Lerch, Zdeněk January 2012 (has links)
The thesis is focused on the issue of the Squalius genus phylogeography in Albania in the Balkan region. Phylogenetic analyses of sequence variation at mitochondrial genes (cytochrome b) were used to examine these issues for the freshwater fish genus Squalius from various river systems in the Adriatic Sea region. There were identified 3 genetic lineages of vague taxonomic position where the genetic variation amount to 1.6-2.1 %. The first lineage is distributed in north of Albania and in the whole Periadriatic region, the second lineage is especially spread to northern part of Albania and the third lineage covers especially the zone of the European ancient lake systems on the Balkan Peninsula (Lake Ohrid and Prespa), from where expands to the southern part of Albania. There sympatrically coincide the both lineage in the hydrological river-lake system of Drin and Skadar. The phylogenetic and taxonomic position of the Squalius genus in the region seems to be interesting topic for subsequent and more detailed study. Keywords: Squalius, Albania, cytochrome b, phylogeography
2

Kolonizace Střední Evropy bentickým sladkovodním korýšem Asellus aquaticus (Isopoda, Crustacea) / Colonisation of Central Europe by benthic frehwater crustacean Asellus aquaticus (Isopoda, Crustacea)

Střížek, Antonín January 2012 (has links)
Longterm climate changes are an inseparable part of the evolution of Earth. In the last few milions of years the changing of glacials and interglacials was as ordinary and regular phenomenon as changing from day to night or from spring to summer. These cycles also have similar influance on evolution of nature on Earth. Eventhough the state of nature appears to us stable for the few last human generations, the reality from the long term point of view is differnt. During these cycles, the location of climatic zones, size of glaciers, deserts, savannahs, steppes or rainforests have changed. Organisms changed locations of their areas of distribution, many nowadays widespread species were pushed into isolated local populations. This Master's thesis reveals the impact of glacial cycles on a freshwater crustacean aquatic Isopod (Asellus aquaticus). Very variable mitochondrial COI gene was sequenced within 139 individuals of this species from 62 different localities in Europe. This data were included into an extensive scope of an already known phylogeographic structure of the continent. An Aquatic Sowbug shows a quite high rate of a genetic heterogenity (maximum Nucleotide Divergence discovered is 0,132 and average is 0,016) in the area of the Czech Republic. Where there are found representatives of two...
3

Fylogeografie temperátních rostlinných druhů se zaměřením na střední Evropu / Phylogeography of temperate plant species with the focus on Central Europe

Daneck, Hana January 2012 (has links)
Phylogeography of temperate plant species with the focus on Central Europe Ph.D. Thesis Hana Daneck Charles University Prague Faculty of Science Department of Botany Supervisor: Prof. RNDr. Karol Marhold, CSc. Consultant: Mgr. Tomáš Fér, Ph.D. Praha 2012 2 Summary This thesis presents contribution to clarification of postglacial history of temperate plant taxa in Europe with the focus on especially interesting region of Central Europe, for which diverse roles in postglacial plant histories were suggested. The first part of the thesis summarises general phylogeographical views and methodological approaches with the respect to species history after the last ice age in Europe. Further, the most important aspects of phylogeography of European temperate plant taxa are discussed. The second part contains a set of papers dealing with selected European temperate plant species, for which phylogeographical patterns throughout their present distribution area were inferred, including assumptions on the origin of their contemporary Central European populations and comparisons with another previously studied species. Paper 1: Phylogeographic pattern of the European forest grass species Hordelymus europaeus: cpDNA evidence. This paper presents phylogeographical pattern based on chloroplast haplotype variation covering the...
4

Fylogeografie a ekologie štěnic rodu Cimex (Heteroptera: Cimicidae) v Evropě; evoluce taxonů a hostitelské specializace / Phylogeography and ecology of the Cimex species (Heteroptera: Cimicidae) in Europe; the evolution of taxa and specialization of hosts

Balvín, Ondřej January 2013 (has links)
The life strategies of parasites and evolutionary mechanisms forming their diversity are particularly various and become frequent objects of study. The Ph.D. thesis deals with one of the obligate ectoparasitic haematophagous groups of insects, the species of the genus Cimex (Heteroptera: Cimicidae). Unlike in most other ectoparasites, the strategy of cimicids consists of remaining hidden in the shelter of their host. They use the host body only to feed and disperse. The advantage of the lower competition with other ectoparasites is counterbalanced by the need for particularly stable blood source, for which the cimicids choose social hosts living in colonies. The most frequent and the original hosts of cimicids are bats. The host range of particular species of Cimicidae is often rather broad. The morphological analysis of the Cimex pipistrelli species group showed, however, differentiation according to host bat species. This suggests a need for adaptation to particular host species within the usual range. The differentiation was not found reflected in the mitochondrial DNA. It is thus possible that cimicids can exhibit phenotype plasticity. The host associated morphological variability likely caused as many as three species of C. pipistrelli group to be described from Europe, from which two were...
5

Postglacilání šíření olše lepkavé (Alnus glutinosa) a olše šedé (Alnus incana) v Evropě / Postglacial colonization of black alder (Alnus glutinosa) and grey alder (Alnus incana) in Europe

Havrdová, Alena January 2015 (has links)
Current species distribution in Europe was mainly influenced by massive climatic and environmental changes during the Quaternary period. Different theories concerning survival of tree species during the last ice age in Europe were proposed and up to date the position of glacial refugia and directions of migration routes are under active debate. My dissertation thesis aimed to combine information from fossil records and genetic analysis to improve knowledge on postglacial history of Alnus glutinosa and Alnus incana. The synthesis of palaeoecological data supports the idea that not only southern but also northern populations were important sources of postglacial Alnus expansion. The delayed Alnus expansion apparent in some regions was likely a result of environmental limitations. Our findings from molecular study showed differences in postglacial histories between temperate A. glutinosa and boreal A. incana. In the case of A. incana, we found an effective refugium in Central Europe located outside classical southern refugia confirming the existence of northern refugia for boreal trees in Europe. Fennoscandian populations are derived from Central-European ones that originated from populations in the Alps. For A. glutinosa, multiple southern refugia were revealed and three main directions of postglacial expansion were proposed: 1) from the northern part of the Iberian Peninsula to Western and Central Europe and subsequently to the British Isles, 2) from the Apennine Peninsula to the Alps, and 3) from the eastern part of the Balkan Peninsula to the Carpathians followed by expansion towards the Northern European plains. It has been shown that colonizing lineages have met several times and formed secondary contact zones with unexpectedly high population genetic diversity in Central Europe and Scandinavia. For the first time, we discovered tetraploid populations of A. glutinosa situated in the putative main glacial refugia on the Iberian and Balkan Peninsulas. Neither of them was probably involved in the colonization of Central and Northern Europe after glacial withdrawal. In conclusion, thanks to extensive population sampling, testing of hypothesis postulated based on fossil data by molecular data and using two molecular markers, i.e. chloroplast DNA and microsatellites, with different mode of inheritance and polymorphisms, this project revealed not only the position of glacial refugia of European tree species and discriminate between effective and non-effective ones, but also help infer the main migration routes. This approach enabled us to change some long-lasting paradigms and brought new pieces of knowledge about postglacial colonization of European tree species.
6

Fylogeografie kudlanky nábožné (Mantis religiosa) ve střední Evropě / Phylogeography of the praying mantis (Mantis religiosa) in central Europe

Urbánková, Hana January 2012 (has links)
The praying mantis (Mantis religiosa) is the only representative of the order Mantodea in central Europe. Within Czech Republic, this species is distributed mostly on xerothermic localities in southern Moravia. However, M. religiosa has been spreading more to the north not only in Czech Republic, but also in other Europian countries recently. The aim of this study was to reconstruct phylogeography based on genetic markers. It seems that studied species was distributed at least in three lineages in Europe, which could be connected with glacial refugias. First lineage was spread to the north probably from Pyrenean peninsula, second lineage from Crimea peninsula and third lineage from Balkan area. Nine microsatellite loci were tested and will be used for consequent sctudy of phylogeography and distribution of M. religiosa within Europe. Keywords: Mantis religiosa, mtDNA, microsatellite, expansion, phylogeography, phylogeny.
7

Factors influencing butterfly diversity of the species-rich Submediterranean region

BARTOŇOVÁ, Alena January 2019 (has links)
This thesis focuses on the history, current state, and conservation of butterfly diversity in the Submediterranean grasslands and Palaearctic steppes. The thesis is introduced with the summary of Cenozoic history of the steppe biome in Eurasia. Then it consists of three studies. The first study describes butterfly communities and microhabitat selection of a steppe specialist butterfly Proterebia afra in two relic grassland areas in the Balkans. Based on genetic markers and samples covering the whole distribution ranges, the second and third studies assess the phylogeography of two steppe butterflies, P. afra and Pseudophilotes bavius, distributed in the Irano-Anatolian region, the Balkans, as well as the northern Palaearctic steppes.
8

Fylogeografie perleťovce mokřadního (\kur{Boloria eunomia}) a srovnání s podobně rozšířenými druhy / Phylogeography of \kur{Boloria eunomia} and comparison with similarly distributed species

MAREŠOVÁ, Jana January 2015 (has links)
Phylogeography, phylogeny and population structure were studied in two similarly distributed butterflies, the Bog Fritillary (Boloria eunomia) and the Small Pearl-bordered Fritillary (Boloria selene). Sequences of mitochondrial gen for COI and nuclear Wingless and Arginine Kinase were used for analyses, for reconstruction of evolutionary relationships within both species and for comparison of phylogeography patterns.
9

Diversity, phylogeny and phylogeography of free-living amoebae

TYML, Tomáš January 2016 (has links)
This thesis consists of seven published papers on free-living amoebae (FLA), members of Amoebozoa, Excavata: Heterolobosea, and Cercozoa, and covers three main topics: (i) FLA as potential fish pathogens, (ii) diversity and phylogeography of FLA, and (iii) FLA as hosts of prokaryotic organisms. Diverse methodological approaches were used including culture-dependent techniques for isolation and identification of free-living amoebae, molecular phylogenetics, fluorescent in situ hybridization, and transmission electron microscopy.
10

Populačně genetická struktura pstruha obecného jako základ úspěšného obhospodařování lososových vod ve střední Evropě

KOHOUT, Jan January 2013 (has links)
The genetic structure of 25 wild populations and five hatchery stocks from Czech Republic and Slovakia were analysed using mitochondrial (control region) and nuclear DNA (microsatellites, LDH-C1*) markers to elucidate the impact of stocking on central European populations of brown trout and to outline further management strategies. It seems that stocking practices have caused massive hybridisation between the Atlantic and Danube brown trout populations in the middle Danube basin and have led to a loss of among-population genetic variability in Slovakia and Moravia. Certain effect of stocking was detected also in the upper Danube, Vistula, Oder and Elbe River basins. However, the populations from the Elbe River basin keep certain level of among-population variability and seem to be less affected by stocking in comparison with the Danube River basin populations. There are some indications of late or post-Pleistocene penetration of the Atlantic basin trout to the Danube River basin. However, it is not clear to which extent the natural contact participated to the present distribution of Atlantic haplotypes and alleles in the Danube River basin. Samples from lower parts of the Danube River basin were therefore analysed using the same mitochondrial and microsatellite markers. Samples from Aegean Sea basin were included in order to reveal genetic variability of eastern Balkan populations and to estimate an impact of stocking in this area. Very low levels of introgression from Atlantic and other non-indigenous trout were found in the eastern Balkan populations. The genetic differentiation among the populations is substantially higher in this area compared to the central European populations. The populations in headwaters of the Otava River (Elbe River basin) were analysed using microsatellites in order to reveal origin of these populations and evaluate the current management strategies of brown trout in Šumava National Park and Protected Landscape Area. The analysed populations were substantially differentiated from the remaining Elbe River basin populations and there was also certain level of genetic structure within trout from the headwaters of the Otava River associated with isolation by a migration barrier and geographic distance. However, stocking with hatchery trout also contributed to the pattern of genetic variability. The population of Borová Lada hatchery, which is used for stocking in Šumava exhibited higher genetic variability compared to the wild populations and it seems to be of heterogeneous origin. Comparisons of the analysed populations with populations from other areas and results from other studies indicated that mtDNA haplotypes from the lower Danube River and southern Black Sea basins differ considerably from a subclade of the Danubian lineage consisting of haplotypes found so far in the most of the Danube River basin and in the Caspian and Aral Sea basins. The results thus evidence a complex evolutionary history of brown trout in the southern and western parts of the Black Sea basin.

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