1. Institute of Environmental Sciences, Jagiellonian University, ul. Gronostajowa 7, 30-387 Krakow, Poland
2. Department of Arctic Biology, The University Centre in Svalbard, Box 156, 9171 Longyearbyen, Norway
3. Institute of Environmental Biology, Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznan, Poland
4. Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
5. Department of Biology, Brooklyn College and The Graduate Center, City University of New York, 2900 Bedford Avenue, Brooklyn, NY 11210, USA