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Phylogeographic patterns and microevolutionary mechanisms in oceanic dolphins
Křišťanová, Žaneta ; Hulva, Pavel (advisor) ; Vokurková, Jana (referee)
This bachelor thesis discusses the current findings regarding the phylogeography of the Delphinidae family. It is mainly focused on phylogenetic structure and speciation of Delphinidae, as well as on the ways of differentiation of trophic niches and the evolution of ecotypes. In the past, the Pleistocene climate oscillation had a major influence on the development of individual species and populations. Currently, it is anthropogenic activities that cause fundamental changes in habitats and thereby change the living conditions for cetaceans. In several species of Delphinidae, the emergence of ecotypes has been recorded, where different populations of the same species use different ecological niches. This thesis is mainly dedicated to the ecotypes of the bottlenose dolphin (Tursiops truncatus). Variability in coloration, body length and spine morphology was noted for individual ecotypes. The spine is an important adaptation to the environment in Delphinidae. In this research, phylogenetic relationships between family of Delphinidae, life strategies and food niche of selected species of the genera Tursiops, Stenella and Delphinus are also described.
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