Biogeographical dynamics of plant taxa and climate-landscape history of the Eurasian steppe belt: Genes documenting history.

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The Eurasian steppe, consisting of the Euro-Siberian part in the west and the Mongol-Chinese part in the east, is the largest steppe region in the Northern Hemisphere. It stretches across 8000 km between the Hungarian basin and the Amur and has some smaller exclaves in Middle Europe and northeastern Asia. Based mainly on macrofossils of vertebrates it is assumed that the formation of the steppe started in the Lower Miocene in Asia and extended westwards in the Middle to Upper Mio¬cene, so that a continuous steppe belt was probably present at the Miocene/Pliocene boundary, latest at the end of the Pliocene. Pristine steppe habitats were widely transformed into agricultural landscapes, while secondary steppe originated in Europe after opening of the dominating forests due to human influence. We propose to apply phylogeographic and biogeographic methods on typical and widespread steppe in-dicator species to understand the geographic origin and the climate-landscape history of the Eurasian steppe belt. Our focal point is the western Eurasian steppe belt, which is the Euro-Siberian steppe. Especially during the Quaternary climate macro-cycles, the steppe faced extensive range shift, range contractions and expansions. We intend to comparatively analyze 15 diverse plant species/species groups with molecular-systematics methods (sequencing of nuclear genes, and genome-wide SNP analysis through GBS) and analyze the data with phylogenetic and phylogeographic methods (dated phylogenies, Bayesian and maximum-likelihood methods on biogeography reconstruction). Thus we want to trace past and ongoing in-situ evolution in expanding and/or subdividing steppe habitats, as well as identify times of intense speciation (or lack thereof) due to climate or geographical changes or stasis, influencing western Eurasia from Miocene till present.