1. Department of BioSciences Program in Ecology and Evolutionary Biology Rice University 6100 Main Street, MS‐170 Houston Texas 77005 USA
2. Department of Biological Sciences Louisiana State University Baton Rouge Louisiana 70808 USA
3. Aarhus Institute of Advanced Studies Aarhus University Høegh‐Guldbergs Gade 6B DK‐8000 Aarhus C Denmark
4. Rocky Mountain Biological Laboratory P.O. Box 519 Crested Butte Colorado 81224 USA
5. Department of Biology University of Maryland College Park Maryland 20742 USA
6. Division of Plant Ecology and Systematics Biology Department, University of Leuven Arenbergpark 31 B‐3001 Heverlee Belgium