Evolution of grassland ecosystems during the Late Miocene in the Eastern Mediterranean

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The reconstruction of palaeovegetation is essentially based on palaeobotanical records and our understanding of the Neogene changes of vegetation in Eurasia dominantly rest upon organic floral remains, which has limited preservation due to diagenesis. As a result, many important aspects of landscape and vegetation history, especially in the Eastern Mediterranean, are still poorly understood. In contrast, primarily siliceous plant fossils (phytoliths) show a high advantage to close our gaps of documentation and knowledge in Neogene vegetation history, because of their diagenetical durability especially under carbonate rich, alkaline and oxygenized conditions. Therefore, phytoliths often provide evidence for the presence of plants growing preferentially under xeric conditions and are not or only rarely documented in the macrobotanical or palynological record (e.g. grasses). Furthermore, phytoliths allow identifying plants to lower taxonomic levels than many pollen would (e.g. distinction of C3 and C4 grasses), thereby helping to resolve a more complete picture of floral and vegetation change, especially issues of grassland histories, in a certain region especially during the Neogene.In our project we perform high-resolution and multi-proxy studies on grassland ecosystem evolution during the Late Miocene (9-6 Ma) in the Eastern Mediterranean, using phytoliths in combinations with palynology, charcoal, carbon isotopy and sedimentology/pedology. Our preliminary results already show that C4-grasses play a major role in SE-European vegetation at least during the latest Tortonian (Pikermian Biome). Our project intend to disentangle the complex evolutionary history of grasslands and woodlands (including the role of fire) in this region, and will further provide unique contributions to the reconstruction of landscapes (vegetation) inhabited by the last Miocene hominids in Europe.