1. Department of Biology, Lund Vision Group, Lund University, 223 62 Lund, Sweden
2. Department of Biology, Animal Physiology, Norwegian University of Science and Technology, 7491 Trondheim, Norway
3. Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, 1000 Ljubljana, Slovenia
4. School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Wits 2050, South Africa
5. Department of Zoology, Division of Functional Morphology, Stockholm University, 106 91 Stockholm, Sweden