1. Unicentre, University of Lausanne; Lausanne Switzerland
2. Laboratory of Evolutionary Botany; University of Neuchâtel; Neuchâtel Switzerland
3. Laboratory of Plant Ecology; University of Basel; Basel Switzerland
4. Laboratoire Interdisciplinaire des Environnements Continentaux LIEC - UMR 7360 CNRS; University of Lorraine; Metz France