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The effect of climatic changes on genetic build-up of populations and their role in promoting adaptive radiations
Štefková Kašparová, Eva ; Janko, Karel (advisor) ; Šabacká, Marie (referee) ; Hulva, Pavel (referee)
The Southern Ocean and its enormously cold, remote and yet the wildest continent, the Antarctic, have experienced numerous rapid climatic changes. It used to be viewed as a barren wasteland with limited knowledge of species diversity or phylogeography. Recently, all aforementioned premises are being increasingly questioned, and this thesis aims to shed light on them. Firstly, multi-locus genetic markers were used to evaluate if it is the lifestyle, benthic or pelagic, including the duration of the pelagic larval period that determines the population connectivity of particular notothenioid species. It was the adult's fish lifestyle along with the oceanographic factors that are responsible for the gene flow between localities. Secondly, is lifestyle a factor determining the extent to which Pleistocene growing grounded ice sheet affected species past population dynamics? The attention was paid to Notothenioidea fish, then to Echinoidea sea urchins, and lastly to NCBI database available antarctic marine shelf and deep-sea fauna. Our findings suggest that the last glacial maximum affected more profoundly the population size of benthic shelf species. At the same time, those living in the water column or inhabiting deep slopes had more ancient population size changes. The Antarctic terrestrial evolution...
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