1. Animal Ecology; Vrije Universiteit Amsterdam; Amsterdam 1081 HV the Netherlands
2. Applied Zoology/Animal Ecology; Freie Universität Berlin; Berlin D-12163 Germany
3. Laboratory of Entomology; Wageningen University; Wageningen 6700 AA the Netherlands
4. Department of Ecology and Evolution; University of Lausanne; Lausanne CH-1015 Switzerland
5. CNRS, ECOBIO (Ecosystèmes, Biodiversité, Evolution); UMR 6553, Université de Rennes; Rennes F-35000 France