1. Department of Biology, California State University, Northridge, CA 91330‐8303, USA;
2. Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, 318 West 12th Avenue, Columbus, OH 43210, USA;
3. School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, UK;
4. Institute of Arctic Biology, University of Alaska, Fairbanks, Alaska 99775‐7000, USA;
5. Department of Biology, Norwegian University of Science and Technology, N‐7491 Trondheim, Norway;
6. Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario M5S 3G5, Canada; Rocky Mountain Biological Laboratory, Crested Butte, CO 81224‐0519, USA