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Phenotypic variability and evolutionary relationships among populations of Primula elatior along an altitudinal gradient
Konečná, Veronika ; Kolář, Filip (advisor) ; Mandák, Bohumil (referee)
Primula elatior represents a promising model for addressing the role of phenotypic plasticity vs. genetic basis of traits in populations differentiated along altitudinal gradients. Phenotypic plasticity is mainly exhibited by the extensive variability of the leaves. Genetic structure of P. elatior populations has been poorly studied so far, the first insights suggested potentially large intraspecific genetic variation. Therefore, the first aim of this study was to reveal the genetic structure as well as morphological and cytological variation of P. elatior populations in the central Europe and compare those to another two intraspecific taxa from the southeastern Europe. Further, I selected three target mountain regions to address the role of altitudinal differentiation for structuring genetic diversity. Finally, I evaluated the status of the putative endemic species Primula elatior subsp. corcontica from the Krkonoše Mts. Microsatellite analyses, multivariate morphometrics and flow cytometry were employed to evaluate variation of P. elatior populations. I identified six major genetic groups by genotyping 12 nuclear microsatellite loci in the study area of central and southeastern Europe with the clear separation of subp. intricata. Focused on the central Europe, three well-defined genetic groups...
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Evolutionary and ecological consequences of polyploidization in Arabidopsis arenosa complex in Western Carpathians
Bayerová, Jana ; Kolář, Filip (advisor) ; Slovák, Marek (referee)
Polyploidization is a key mechanism of rapid speciation, with many phenotypic consequences which extent, however, is poorly understood. A deeper understanding of the evolutionary implications of genome duplication is limited due to lack of knowledge of the links between changes in genome, the phenotype of the individual and environmental constraints. Natural lineages closely related to model species represent the ideal systems for addressing such questions. The thesis is thus focuses on highly promising yet overlooked di-polyploid system within Arabidopsis genus. In the western Carpathians morphologically distinct populations of diploid and tetraploid plants of Arabidopsis arenosa grow along a marked altitudinal gradient. Using high-throughput DNA sequencing, measuring morphological characteristics and collecting ecological data of high alpine and foothill populations I try to reveal main trends of genetic and morphological variability of these populations. Additionaly, using morphometrics of natural and experimentally planted populations we want to test the hypothesis whether morphological divergence of alpine and foothill populations has a genetic basis or is driven by phenotypic plasticity. The presented thesis is an important multidisciplinary combination of genetic research on natural related of model...
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Influence of maternal effect on body size evolution in geckos
Kubát, Jan ; Kratochvíl, Lukáš (advisor) ; Frýdlová, Petra (referee)
In this diploma thesis has been tested potential of maternal influences on body growth at two model groups of geckos with large interspecific body size variability. The effect of egg manipulation to hatchling size was proved to be significant for hatchlings at both model species Paroedura picta and Goniurosaurus lichtenfelderi. However, in adult animals, there were no more significant body size differences caused by egg manipulation. It leads to conclusion that both species of geckos have compensatory growth and its adult size is likely to be primarily genetically determined. Key words: maternal effect, egg manipulation, body growth, allometric engeneering, Paroedura picta, Goniurosaurus lichtenfelderi
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Plant adaptation to climate change
Koláříková, Veronika ; Münzbergová, Zuzana (advisor) ; Sklenář, Petr (referee)
Climate change represents important selective force for plants. They have to deal with this change otherwise they are facing the risk of extinction. Understanding the mechanism which plants use to avoid the risk is essential for effective conservation of biodiversity. The climate change can exceed the tolerance of plants to abiotic factors. The plants can react to the changes by migration, phenotypic plasticity, evolutionary adaption or by a combination of these strategies. Phenotypic plasticity and evolutionary adaption are manifested by a change of physiology, morphology and/or phenology of plants. This work summarizes the findings of these ecological and evolutionary strategies and also presents methods used for studying species response to climate change. Powered by TCPDF (www.tcpdf.org)
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The effect of urbanization on life-history strategies in birds
Houšková, Karolína ; Sedláček, Ondřej (advisor) ; Poláková, Simona (referee)
Urbanisation process is recently a wide-spread process that causes high-impact environmental transformation. Habitats affected by urbanization tend to change substantially and ongoing changes influence organisms living in this environment. Urban environment modifies many abiotic conditions (e.g. temperature, artificial light and noise) and biotic factors (e.g. food supply, parasite prevalence, predation pressure) in comparison to natural habitats. In this manner, especially urban bird populations have recently gained broad attention by an increasing number of ecologists. Urban avoiders - typically sensitive and specialized bird species often vanish from urbanized landscapes. However, many bird species were able to colonize urban environment and coexist successfully with man. Populations of birds living in such a new type of environment show many characteristics different from populations living in original habitats. The objective of this work is to review current studies about changes of life strategies in urban bird populations such as modifications of acoustic signals, differences in reproductive and food ecology and physiological or behavioural responses.
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Influence of environmental variables on the shape of ultraviolet pattern in Gonepteryx rhamni
Pecháček, Pavel ; Kleisner, Karel (advisor) ; Hořák, David (referee)
Many species are sensitive to a light in ultraviolet spectrum. Some species have surface patterns that reflect ultraviolet light. These markings have been observed in many animal taxa; butterflies (Lepidoptera) are no exception. UV-reflectance in butterflies has been primarily connected to sexual selection and in this respect it has been a subject of many studies. In my work I propose an alternative view to this phenomenon. The aim of my work is to reveal how a particular environmental factors influence the morphospace of UV- reflectant patterns and wing shape of the Gonepteryx rhamni (Pieridae). The effect of various environmental factors (latitude, longitude, altitude, mean annual temperature, mean annual precipitation, normalized difference vegetation index - NDVI or net primary productivity - NPP) on wing morphospace was tested using the methods of Geometric morphometrics. I have also studied shape variability among the males and females, specimens from different locations and differences in morphospace of several G. rhamni subspecies. The dataset used in this analysis includes 118 males and 67 females from the Palearctic ecozone. The effect of almost all environmental (except to NDVI and NPP) predictors on shape of the UV-pattern and wing margin was significant in the case of males. In the...
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Phenotypic plasticity and its role in plant invasions
Hlavička, Matěj ; Herben, Tomáš (advisor) ; Skálová, Hana (referee)
Phenotypic plasticity is the ability of given genotype to produce different phenotypes as a response to environmental cues. Its capability of adaptive response draws an attention of invasion biologists. Although many studies have been performed, the true role of plasticity in an invasion process is still unclear. Comparative experiments suffer from several major constraints - insufficiency in revealing adaptive value of plastic response and uncertain linkage between plasticity and trait value. Further experiments could be focused to reaction norms of fitness instead of trait plasticity. Also, the interspecific interaction of plastic responses is definitely an underestimated mechanism and deserves far more attention than it does today. Possible implications of plant phenotypic plasticity in predicting future invasions require further reaserch.
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Population differentiation of Ochrophytes
Mensová, Anna ; Jurdíková, Katarína (advisor) ; Kulichová, Jana (referee)
This bachelor thesis deals with a differentiation of populations of Ochrophytes (photosynthetic Stramenopiles). Natural populations can differ in many aspects and their differentiation is observed on several levels. Ecophysiological and morphological differences are very often caused by phenotypic plasticity, which is a flexible answer to changing conditions of habitats. Genetic differentiation could express an adaptation to the local environmental conditions. The adaptation and a long-term isolation of populations are considered to be the leading factors in genetic differentiation. The other factors contributing to genetic differentiation are random evolutionary events such as founder effect or genetic drift. Detailed studies of populations lead to uncover the factors that cause the differentiation of populations as well as they contribute to the understanding of speciation mechanisms. The thesis compiled the information about different types of variability among populations within the classes of Ochrophytes.
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Integration of clonal plants in heterogeneous environment
Vinšová, Jana ; Weiser, Martin (advisor) ; Macek, Petr (referee)
Clonal plants may be able to cope with spatial and temporal heterogeneity due to the physiological integration of ramets. To begin with, I discuss basic characteristics of clonal plants and then I provide a review of theoretical and empirical work dealing with the advantages and disadvantages of clonal growth in heterogenous conditions. Three main traits - translocation of resources, division of labour and foraging - are examined in terms of their contribution to the success of clonal plants. Despite a large amount of attention which this topic has received in the past few decades, a number of issues still remain unclear.
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Phenotypic plasticity of Daphnia cucullata in two lowland ponds
Volemanová, Eva ; Petrusek, Adam (advisor) ; Pichlová, Radka (referee)
4 ABSTRACT Characteristic high helmets in Daphnia cucullata, which increase resistance of Daphnia against various invertebrate predators, can be induced by chemical cues released by these invertebrates but also by small-scale turbulence. I evaluated the response of D. cucullata to both factors in several clones originating from two riverine pools differing in their predator regime. In a large pool, the dominant invertebrate predator is the cladoceran Leptodora kindtii, and the Daphnia population there shows a typical cyclomorphosis. In the second (small) pool, Daphnia do not produce helmets, despite the presence of the phantom midge larvae Chaoborus flavicans. I compared phenotypic changes of Daphnia cucullata clones from these pools to Chaoborus kairomones and to a small-scale turbulence in laboratory experiments. Kairomones induced significantly longer helmets in clones from both pools; however, only clones form the large pool reacted also to turbulence. As all daphnids in the experiments responded to chemical cues from Chaoborus, I assume that either the kairomone dose under natural conditions in the small pool is too low to induce helmets or the phenotypic response of the local population is mediated by other factors. On the other hand, the variation of response to small-scale turbulence suggests that...
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