1. Museum of Vertebrate Zoology, University of California, Berkeley, CA 94720–3160, USA
2. Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
3. Department of Integrative Biology, University of California, Berkeley, CA 94720–3160, USA
4. Biological Sciences Department, California Polytechnic State University, San Luis Obispo, CA 93407–0401, USA
5. Department of Environmental Science, Policy and Management, University of California, Berkeley, CA 94720–3114, USA
6. Research School of Biology and Centre for Biodiversity Analysis, The Australian National University, Canberra, ACT 0200, Australia
7. The Commonwealth Scientific and Industrial Research Organization Ecosystem Sciences Division, Canberra, ACT 2601, Australia