1. Research Group Evolutionary Ecology of Variation; Max Planck Institute for Ornithology; Seewiesen Germany
2. Department of Behavioral Ecology and Evolutionary Genetics; Max Planck Institute for Ornithology; Seewiesen Germany
3. Current Address: Center for Biodiversity Dynamics; Norwegian University of Science and Technology; Trondheim Norway
4. Current Address: Royal Netherlands Institute for Sea Research (NIOZ); Department of Coastal Studies (COS); Utrecht University; Den Burg Texel the Netherlands
5. Current Address: Department of Biology; University of Kentucky; Lexington Kentucky
6. Current Address: Conservation Ecology Group; Groningen Institute for Evolutionary Life Sciences (GELIFES); University of Groningen; Groningen the Netherlands
7. Behavioural Ecology; Department of Biology; Ludwig-Maximilians University of Munich; Planegg-Martinsried Germany