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Conservation of populations on the edge of geographical distribution
Pešová, Lucie ; Sedláček, Ondřej (advisor) ; Šípek, Petr (referee)
Populations on the edge of the range are often considered less valuable for conservation with regard to core populations of the species. These populations are often small, isolated and less genetically variable, and are therefore more prone to extinction. On the other hand, there are some studies claiming that some peripheral populations could have genetically unique allels which could help them adapt to changing environmental conditions. They thus have a big speciation potential. Peripheral populations could also occur behind state borders, where the species has conservation status, despite the fact that it is a common species somewhere else in its range. Due to this contradiction, peripheral populations are a delicate topic of discussion in the scientific community. In this paper I summarized the features of populations on the edge and also factors which limit them. Furthermore, population dynamics of these populations and summary of the main genetic processes taking place in small populations are outlined here. Next there are arguments for and against conservation of populations on the edge. In conclusion I give model examples of species on the periphery, demonstrating their features and reasons for their possible conservation. Key words: population, conservation, peripheral, marginal, range...
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Spreading of praying mantis (Mantis religiosa) in Europe
Vitáček, Jakub ; Janšta, Petr (advisor) ; Gvoždík, Václav (referee)
Climate change is one of the most important factor determining species ranges. In Europe there is now evidence for northward areal expansion in many Mediterranean insects including the praying mantis (Mantis religiosa). This species is the only representative of the order Mantodea inhabiting central Europe. The northern edge of the species distribution currently reaches latitude 53ř North. Although, the praying mantis is well known insect there is not enough evidence about its phylogeography. In this work three mitochondrial genes (COI, COII, Cyt b) were selected for phylogenetic study. Results indicate three statistically supported distinct lineages in Europe: Eastern European, Central European and Western European. Presumably these lineages are consistent with isolation during the last glacial and re-colonization from glacial refugia. Reduced haplotype diversity on the northern edge suggests currently established populations at the northern distribution border. To validate mtDNA results it was also considered four microsatellite loci. Due to different type of inheritance mtDNA and nuclear DNA it is possible to compare two independent genetic datasets. Microsatellite analysis confirmed results obtained on mitochondrial data. Three major genetic clusters were found: east, west and central. Spatial...
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