1. Natural History Museum of Denmark, University of Copenhagen, Sølvgade 83S, DK-1307 Copenhagen K, Denmark
2. Marine Biological Section, Department of Biology, University of Copenhagen, Øster Farimagsgade 2D, DK-1353 Copenhagen K, Denmark
3. Department of Geography and Geology, University of Copenhagen, Øster Voldgade 10, 1350 Copenhagen K, Denmark
4. Department of Marine Ecology, University of Gothenburg, Box 461, SE 405 30 Göteborg, Sweden
5. Section of Terrestrial Ecology, Department of Biology, University of Copenhagen, Øster Farimagsgade 2D, DK-1353 Copenhagen K, Denmark