1. Department of Biology Shepherd University Shepherdstown West Virginia USA
2. Department of Biology Colgate University Hamilton New York USA
3. Department of Ecology and Evolutionary Biology University of California Santa Cruz California USA
4. Natural Science Division Pepperdine University Malibu California USA
5. Department of Botany, National Museum of Natural History Smithsonian Institution Washington District of Columbia USA
6. Red de Ecología Funcional Instituto de Ecología A.C. Xalapa Mexico
7. Institute for Systematic Botany and Ecology University of Ulm Ulm Germany