Comparative phylogeography of three woody species to infer vegetation history of the Patagonian steppe

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Patagonia, the southern-most part of South America, is an area where up to now very few phylogeographic studies of plants have been conducted. Thus, knowledge of vegetation history and hotspots of biodiversity is scarce. Two earlier studies found very similar phylogeographic patterns in four herbaceous species of the Patagonian steppe, the dominant vegetation unit of Patagonia east of the Andes. Within this project the phylogeography of three characteristic woody species of this vegetation unit will be analyzed. We will use sequences of the chloroplast genome and nuclear microsatellite loci as molecular markers to detect geo¬graphic patterns of genetic diversity. In addition we will use environmental niche modeling to characterize niche parameters and infer past species distribution. The main objective of this study is to infer if similar phylogeographic patterns indicate a common Pleistocene history of these species despite their ecological differences, or if the species reacted differently to past changing climate. By integrating the results of this study with that of the few earlier analyses of Patagonian steppe taxa it will be possible to reach a general understanding of the vege¬tation history of this plant community, particularly if steppe vegetation shifted its distribution as a unit or if the composition of the steppe changed repeatedly with Pleistocene climate changes.