1. Department of Animal Morphology, Faculty of Biology, Adam Mickiewicz University, Poznan, Poland
2. Laboratory and Museum of Evolutionary Ecology, Department of Ecology, Faculty of Humanities and Natural Sciences, University of Prešov, Prešov, Slovakia
3. Department of Avian Biology and Ecology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
4. Institute of Biology, University of Szczecin, Szczecin, Poland