Duration: 02/2013 - 01/2016
This study will provide the first detailed assessment of the composition of European freshwater gastropods during the Neogene and Quaternary at species, genus and family levels, with emphasis on lake faunas. Biodiversity and composition of Holocene lake faunas seem to be strongly influenced by the Quaternary Ice Ages. Several short-lived Miocene lakes, however, are strikingly modern in their generic inventory and genus/species relations, suggesting that the modern composition is not necessarily a young pattern, explained only by the glacial bottleneck. In contrast, the modern long-lived lakes of Europe host gastropod assemblages with high endemicity and striking similarities with pre-Pleistocene lake faunas. The origin of these modern faunas, however, is still enigmatic.
In a first step, the γ-diversity of several hundred modern and fossil European lakes will be evaluated. An international expert team of palaeontologists and limnologists, with long-lasting experience with the fossil and modern faunas, European stratigraphy, and a deep knowledge on the exhaustive relevant literature, is available for data acquisition, evaluation and controlling. In the next step the huge accumulation of data will be made available permanently for the public via the FreshGEN-database (Freshwater Gastropods of the European Neogene). This database will be set up to meet current standards for management and storing of electronic biodiversity data and will be compatible with related projects. The most important topics to be tackled based on the data, are to search for factors, which explain the γ-diversities through time and to look for geographic gradients in species richness and/or faunal composition. Diversity data and inter-lake comparison will allow estimating endemism rates and quantitatively defining biodiversity hotspots in present and past lakes. Shells-sizes of all taxa will be evaluated to search for general patterns and to define phases of conspicuous gigantism.
The well resolved climate history of Europe during the last 23 million years will be a frame for linking species- and supraspecific compositions with climatic trends and events. Ideally, the project will shed light on the origin of modern lake faunas by the intense cooperation between zoologists and palaeontologists.
A major aim is to map and define a statistics-based Pan-European biogeography and palaeobiogeography of Neogene to Quaternary freshwater systems. Once established, this database will be open for geographic and/or stratigraphic expansion. Finally, the data are a solid base to estimate the (future) anthropogenic impact on Holocene lake faunas.