Quaking aspen (Populus tremuloides) has the largest natural distribution of any tree native to North America, ranging from Alaska through the breadth of Canada and south to mid-Mexico. The Laurentide ice sheet occupied most of the current range of P. tremuloides until the late Pleistocene epoch, so this species has undergone a significant, geologically recent range expansion. Surprisingly, range-wide patterns of genetic variation in P. tremuloides have never been described. Using a sample set representing the full longitudinal and latitudinal extent of the species distribution, I have conducted a phylogeographic analysis for P. tremuloides. Preliminary results comparing both nuclear and chloroplast DNA sequences revealed surprisingly low levels of divergence across the range. Because of this remarkably shallow genetic divergence among aspen populations, I used a set of rapidly-evolving molecular markers (microsatellites) to describe patterns of gene flow and diversity and to correlate those patterns with landscape features and histories. I analyzed eight microsatellite loci in 794 individuals from 30 sampling sites. From this multilocus data set, I identified pronounced genetic structuring across the range. Strikingly, sampling sites representing the southwestern portion of the range, the western United States and Mexico, form a distinct cluster. Sites within this southwestern cluster display dramatically reduced within-site genetic diversity but elevated regional genetic diversity, which suggests that populations in the southwestern portion of the range make up a stable edge persisting through multiple climate oscillations. Based on the uniqueness of the southwestern cluster and the climatic differences between the southwest and northern portions of the range, I propose that the southwestern cluster may represent a distinct ecotype. I also identified hotspots of diversity that correspond with potential refugia during the last glacial maximum but additional work is needed to refine these patterns. Further, my findings provide a solid foundation for a range of future studies on adaptive genetic and trait variation in this species.

During the climate oscillations of the Pleistocene an ice sheet formed covering Fennoscandia. Traditionally, Scots pine and many other species were believed to have persisted in glacial refugia in the south, only returning to northern latitudes as the ice retreated. Recent studies have demonstrated the existence of glacial refugia in higher latitudes, in fact, cryptic refugia as far north as Lofoten have been suggested. I investigated the potential existence of such a refugium for Scots pine using mtDNA markers Nad 1-B/C, Nad 7-1 and NODE_new_663. Results show an east/west distribution of the mtDNA polymorphisms at Nad 1 and Nad 7 across Fennoscandia, where multi-locus mitotype bb is more common in the east and ba is more common in the west, in accordance with the hypothesis of a glacial refugium in northeast Europe. Further, the bb mitotype was discovered to be more widespread in Fennoscandia than previously documented. No unique mitotype was discovered in northwestern Fennoscandian populations to support the hypothesis of a glacial refugium along the northwest coast of Norway. Genetic diversity was high and even across Fennoscandia and differences in diversity were not significantly correlated with distance between populations, possibly due to high mutation-rates for the NODE_new_663 minisatellite locus or as a result from admixture between multiple glacial refugia in the area. No conclusive evidence regarding the existence of a glacial refugium in Fennoscandia was discovered and needs to be studied further.

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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The concept of biodiversity – the phenotypic and genotypic variation among organisms – is central to conservation biology. There is growing recognition that biodiversity does not exist in isolation, but rather is intrinsically and evolutionarily linked to cultural diversity and indigenous knowledge systems. In Canada, caribou (Rangifer tarandus) occupy a central place in the livelihoods and identities of indigenous people and display substantial variation across their distribution. However, quantifying caribou intraspecific variation has proven challenging. Interdisciplinary approaches are necessary to produce effective species characterizations and conservation strategies that acknowledge the interdependent relationships between people and nature in complex social-ecological systems. In this dissertation I use multiple disciplinary traditions to develop comprehensive and united representations of caribou variation through an exploration of population genetics, phylogenetics, traditional knowledge, language, and visual approaches in the Sahtú region of the Northwest Territories, Canada. First, I examine caribou variation through analysis of population genetics and the relationships Dene and Métis people establish with animals within bioculturally diverse systems. Next, I focus on how the Pleistocene glacial-interglacial cycles have shaped the current patterns of caribou phylogeographic lineage diversification. Finally, I explore how art can be used to facilitate cross-cultural collaboration and externalize the unique heterogeneity of biocultural diversity. The results demonstrate a broad scale understanding of the distribution, spatial organization, and the degree of differentiation of caribou populations in the region. I found evidence for caribou population differentiation that corresponds to the caribou types recognized by Dene people: tǫdzı “boreal woodland caribou,” ɂekwę́ “barren-ground caribou,” and shúhta ɂepę́ “mountain caribou.” Phylogenetic results reveal that in their northern margin the boreal ecotype of woodland caribou evolved independently from the northern Beringian lineage in contrast with southern boreal caribou which belong to the sub-Laurentide refugia lineage. In addition, I demonstrate how art can be used improve communication, participation, and knowledge production among interdisciplinary research collaborations and across language and knowledge systems. A collaborative process of research that facilitates łeghágots'enetę “learning together” has the potential to produce sustainable conservation solutions, develop efficient and effective wildlife management policies, and ensure caribou remain an important part of the landscape. / February 2017

Adaptive population shifts in response to climate change Ing. Michaela Horníková, Doctoral thesis Abstract Understanding of species' reactions to past climate and environmental changes is a hot topic in many fields of biology as it is relevant also for addressing species' future under the contemporary climate change. Using an emerging model species, the bank vole, I combine genomic phylogeographic data with information on known intraspecific functional variability and environmental niche modelling and aim to elucidate the particular role of intraspecific variation and ultimately selection in shaping the species' response to the climatic and environmental changes after the end of the last glaciation. Based on the mtDNA markers, bank voles exhibit a complex phylogeographic pattern suggesting population replacement events during the postglacial recolonization of Europe and thus possible involvement of selection in the process. An extensive dataset of more than 6000 SNPs was used to search for signs of population replacement in the bank vole genomic DNA and to investigate the species' postglacial recolonization history throughout its European distribution range. The genomic data revealed even more complex population history than previously detected with mtDNA markers, including not only admixture but also...