1. Center for Macroecology, Evolution, and Climate, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen, Denmark.
2. Department of Biology, Lund University, Ecology Building, SE-22362 Lund, Sweden.
3. Montagu’s Harrier Foundation and Animal Ecology Group, Centre for Ecological and Evolutionary Studies, Post Office Box 11103, Groningen University, NL-9700 CC Groningen, Netherlands.
4. Natural History Museum, Center for Macroecology, Evolution and Climate, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen, Denmark.