1. Department of Evolution and Ecology, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA
2. Institute of Ecology and Evolution, University of Bern, Bern, Switzerland 3012
3. Department of Biological Sciences, Towson University, Towson, MD 21252, USA
4. Department of Infectious Diseases and Pathology, College of Veterinary Medicine, University of Florida, USA