1. Department of Integrative Biology, Museum of Vertebrate Zoology, University of California, Berkeley, CA 94720, USA
2. The Rocky Mountain Biological Laboratory, Crested Butte, CO 81224, USA
3. Department of Biology, Indiana University Purdue University Fort Wayne, Fort Wayne, IN 46805, USA
4. Department of Ecology and Evolutionary Biology, University of California, 6121 Young Drive South, Los Angeles, CA 90095-1606, USA