1. Plant Ecology and Conservation Biology, Institute of Biochemistry and Biology, University of Potsdam; Maulbeerallee 2, Potsdam 14469 Germany
2. Equipe Génétique et Environnement, Institut des Sciences de l'Evolution de Montpellier, UMR-CNRS 5554, Université Montpellier II, 34095; Montpellier cedex 5 France
3. The Movement Ecology Laboratory, Department of Evolution, Systematics and Ecology, Alexander Silberman Institute for Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus at Givat Ram; Jerusalem 91904 Israel