1. Mammal Research Institute, Polish Academy of Sciences, 17-230 Białowieża, Poland.
2. Institute of Integrative and Comparative Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK.
3. Université Paris-Sud, Laboratoire Ecologie, Systématique et Evolution, UMR 8079, Orsay CEDEX, F-91405; CNRS, UMR 8079, Orsay CEDEX, F-91405.