1. Department of Ecology and Evolutionary Biology; University of Tennessee; 569 Dabney Hall Knoxville TN 37996 USA
2. Rocky Mountain Biological Laboratory; P.O. Box 615 Crested Butte CO 81224 USA
3. Rubenstein School of Environment and Natural Resources; University of Vermont; Burlington VT 05405 USA
4. Center for Macroecology; Evolution, and Climate Natural History Museum of Denmark; Copenhagen 2100 Denmark