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Homosexuality in the Age of Oscar Wilde
KOLÁŘ, Filip
The introductory part of this bachelor 's attempts to outline the historical context of the times that preceded the Victorian era. Homosexuality in ancient Greece and in Czech lands is explored in the first chapter. This chapter also deals with the evolution of definition of sexual scandal in different times. In the following chapter, the attention is paid to an English educational system, which shaped society to a large extent. It highlights the fact that homosexual activities were performed by young students, who were to become a future elite of British society. Three important scholars are also mentioned in this chapter, John A. Symonds, Edward Carpenter, and Havelock Ellis. The last two chapters deal with homosexuality in Victoria England and its empire, with Oscar Wilde trials and places certain elements in context of more liberal France, where Oscar Wilde fled.
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Evolutionary role of triploids in diploid-tetraploid populations of Arabidopsis arenosa and Cardamine amara
Voltrová, Alena ; Kolář, Filip (advisor) ; Chrtek, Jindřich (referee)
This thesis addresses the evolutionary potential of interploidy gene flow mediated by triploid individuals of two mixed-ploidy species, Arabidopsis arenosa and Cardamine amara, both from Brassicaceae family. In natural secondary contact zones formed by diploid and autotetraploid cytotypes, triploids of both species are rarely occurring, being represented only by 0.2 % and 2.5 % of individuals in A. arenosa and C. amara, respectively. Yet their role in gene flow between parental diploid-tetraploid populations remain unclear although genetic data confirmed significant traces of interploidy introgression. By crossing experiments of both species of triploids with their parental ploidies, I addressed the potential of triploids as mediators of gene flow. Specifically, the fertility of triploids and their ability to backcross with their diploid and tetraploid parents. Successful crosses involving triploids both as mothers and fathers demonstrated triploid's ability to form viable male and female gametes. A significant fraction of seeds produced out of these crossings was able to germinate and survive. The progeny was largely aneuploid, but both basic euploids were observed, demonstrating a clear pathway how triploids can backcross back towards diploid and tetraploid ploidies. In C. amara, field...
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Role of metal hyperaccumulation in serpentine adaptation
Havlíková, Karolína ; Kolář, Filip (advisor) ; Stiblíková, Pavlína (referee)
Throughout our planet's history, plant and organism communities have faced many severe environmental challenges. Changing environment forces leads to the adaptation of plants to specific conditions, such as serpentine soils, specific by their natural toxicity. There are several possible adaptation mechanisms to serpentine challenges and one of them is probably hyperaccumulation. Hyperaccumulation is the ability of a plant to accumulate large amounts of heavy metals without signs of toxicity, and most such plants live on serpentine soil. However, it is far from known how many plants have such an ability. Some plant species inhabit normal soils as well as serpentine soils. These so-called facultative hyperaccumulators represent ideal study systems for addressing the role of hyperaccumulation the adaptation towards toxic soils. These species are most often found in the Brassicaceae family and also in the genus Alyssum s.l.. So far understudied species Alyssum gmelinii may be one of these promising new model species as it grows on a normal substrate, as well as on a serpentine. My bachelor thesis tries addresses the role of hyperaccumulation in substrate adaptation both theoretically and in a practical experiment with replicated natural populations of A. gmelinii. Two serpentine and two non-serpentine...
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Processes governing sympatric coexistence of di- and tetraploid cytotypes in primary contact zone of Knautia arvensis agg.
Hanzl, Martin ; Kolář, Filip (advisor) ; Duchoslav, Martin (referee)
Intensive cytotype screening in the primary contact zone of relict serpentine Knautia arvensis agg. revealed a striking predominance of the derivative tetraploid (81 % of subpopulations) over the diploid maternal race. Eleven mixed-ploidy subpopulations with the close spatial proximity of both cytotypes were identified. Flow cytometric analyses of almost 5 000 individuals led to discovery of two extremely rare minority cytotypes (3x, 6x). Vegetation analyses were made at two different spatial scales and in both cases confirmed the absence of distinctions in habitat preferences of cytotypes. Slight microhabitat segregation of cytotypes was however apparent at the finest spatial scales. Cytotype distribution within mixed-ploidy sites was not random. Striking patterns of cytotype clumping into cytotype uniform patches and negative spatial correlations between diploid and tetraploid individuals were apparent at all sites. Distribution of life cycle stages of diploids and tetraploids within the mixed-ploidy subpopulations were significantly different. The clonality was the most common mode of reproduction in the subpopulations of both cytotypes. Seedlings accounted for only 7 % of new plants. Significant distinctions in the plant vigour between the cytotypes were showed during the in situ comparison in...
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Microevolutionary processes in mixed-ploidy populations of plants
Čertner, Martin ; Kolář, Filip (advisor) ; Ramsey, Justin (referee) ; Duchoslav, Martin (referee)
Polyploidization (whole-genome duplication) is widely considered one of the most important evolutionary forces driving the diversification of flowering plants. Polyploids tend to originate recurrently and many plant species retain individuals of two or more different ploidy levels in certain parts of their distributional range of even within their populations. The main aim of this thesis was to address the understudied aspects of polyploid speciation by employing new, convenient methods and/or studying plant model systems with unique features. Difference in monoploid genome size of Tripleurospermum inodorum (Asteraceae) cytotypes provided a unique opportunity for addressing the rate of spontaneous polyploidization in natural populations by enabling the easy distinction of neopolyploid mutants from long-established polyploids in routine flow-cytometric analyses. Repeated ploidy screening in mixed-ploidy populations of annual T. inodorum have been, to our knowledge, the very first attempt to document temporal changes in cytotype composition in situ. In spite of considerable between- year oscillations in cytotype frequencies, both diploids and tetraploids usually persisted locally for several consecutive years. The common incidence of such ploidy mixtures along with a partial fertility of triploid...
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Genome size evolution in the Zingiberaceae
Pospíšilová, Monika ; Fér, Tomáš (advisor) ; Kolář, Filip (referee)
The purpose of this study is to evaluate the existing knowledge on the evolution of genome size and also to focus on genome in the phylogenetic context. Among angiosperms we find a wide range of C-values (1C = 0.63 pg ? 1C = 127.4 pg), but the modal value is 0.6 pg. We still do not know much about the nature and mechanisms of plant genome size evolution, but we are learning more and more every year. There are already dozens of studies dealing with the dynamics of genome size of smaller taxonomic groups and on four of these they demonstrate possible approaches. Researching within higher taxonomic groups such as families is difficult and so more valuable. New research on the evolution of genome size in the family Zingiberaceae has started and my master thesis dealing with the Globbeae tribe should be part of it.
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Ecological and evolutionary processes in primary contact zone of cytotypes of Knautia arvensis agg.
Hanzl, Martin ; Kolář, Filip (advisor) ; Urfus, Tomáš (referee)
Genome duplication events have played a crucial role in plant evolution. According to recent estimates, nearly all the angiosperms are ancient polyploids. However, establishment of new polyploid lineages within diploid populations seemed to be very unlikely, based on theoretical analyses. Reproductive interactions between the cytotypes (so-called "minority cytotype exclusion") and resource competition might eventually lead to polyploid extinction. On the other hand, the whole variety of factors may compensate both processes under natural conditions (e.g. autogamy, assorative mating, spatial separation of cytotypes). Polyploid establishment in sympatry with diploid progenitor might thus not be as restricted, as previously thought. Subsequent cytotype coexistence may represent a stable equilibrium, or just a transition leading to extinction of one chromosomal race. It is usually almost impossible to discriminate between these alternatives. Polyploid range expansions are usually accompanied by competitive exclusion of diploid cytotype or colonization of new areas and habitats. When two cytological races meet, zones of contact are often formed. Contact zones could be divided into primary and secondary ones. Primary contact zones arise as a consequence of new polyploid emergence within the progenitor's...
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Evolutionary history of tetraploid representatives Galium pusillum group (sect. Leptogalium) in central Europe. Allopatric differentiation of Czech endemic species G. sudeticum
Knotek, Adam ; Kolář, Filip (advisor) ; Chrtek, Jindřich (referee)
The presented study tries to reveal the evolutionary history of polyploid complex Galium pusillum aiming on a rare czech endemic species G. sudeticum, an ideal model to study allopatric speciation in the context of Central European (post)glacial development. The species G. sudeticum grows in Krkonose Mts. and on serpentines in western Bohemia (Slavkovský les) more than 200 kilometers away. Our morphological and molecular data suggest a clearly different history of its two isolated areas. The populations in Krkonose Mts. are probable relics of mountainous species G. anisophyllon which was there on its northern border of occurence and hybridized with lowland species G. valdepilosum during postglacial vegetations shifts. This fact is well supported by intermediate position of Krkonose Mts. populations in both morphological and molecular AFLP analyses and by sharing the same chloroplast haplotype with geographically close lowland populations. On the other hand the serpentine lowland populations in western Bohemia are both morphologicaly and genetically indistinguishable from G. valdepilosum. Distinct genetic lineage of few populations belonging to G. valdepilosum (incl. one traditionaly referred as G. sudeticum) was found in western Bohemia and Bavaria, located on relic stands (calcareous and serpentine...
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Evolutionary drivers and consequences of parallel evolution in plants
Konečná, Veronika ; Kolář, Filip (advisor) ; Papadopulos, Alexander (referee) ; Lenhard, Michael (referee)
Parallel adaptation to similar environmental pressures provides ideal model systems to study the repeatability of evolution in nature. Such replicated natural experiments can also provide important insights into the genomic basis of adaptations. However, well-documented examples are rare, particularly in plants. Here, I brought new evidence of parallel evolution from three plant systems facing one of the most challenging selective environments - alpine stands and toxic serpentine soils. Further, I leveraged the cases of naturally replicated parallel adaptation in Arabidopsis arenosa to study the extent of phenotypic and genomic parallelism and to address the evolutionary sources of the parallel genetic underpinnings. By combining population genetic and experimental approaches I documented the complex interplay of adaptive, historical, and ecological processes in parallel evolution. The island-like distribution of high-elevation and serpentine habitats promoted their independent colonizations by distinct genetic lineages of A. arenosa and Primula elatior separately in each geographic region. Further, I showed how challenging environments structure genetic diversity within a species. For instance, I found higher genetic differentiation among (sub)alpine populations than among foothill populations....
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The role of triploid hybrids in mixed-ploidy populations of Tripleurospermum inodorum (Asteraceae)
Jirsáková, Hana ; Čertner, Martin (advisor) ; Kolář, Filip (referee)
The doubling of the nuclear genome is considered to be one of the main ways in which new sympatry plant species can arise. Polyploidy is also generally a significant source of new evolutionarily advantageous abilities. However, it is not always that way, polyploids with an odd number of chromosome sets have often limited viability and fertility. In cytotype mixed populations of diploids and tetraploids, or in diploid populations alone with the contribution of high rate of unreduced gametes formation may produce triploid hybrids. In some cases, their vitality is even comparable with parental cytotypes but they produce only a small number of offsprings and in addition of different ploidy levels. Although it has been recently thought that they have no evolutionary significance, now based on many experimental works it is known with confidence that they can significantly participate in the new polyploid formation. If triploids occur in the population with sufficient frequency, they may play a role in stabilizing of the common coexistence of diploid and tetraploid cytotypes. Triploid hybrids may despite their limited fertility contribute to the bi-directional gene flow between their parents, and thus overcome the barrier of their different ploidy levels. A suitable model to study the role which can the triploid...
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