1. Smithsonian Tropical Research Institute, Apartado 0843–03092, Balboa, Panama
2. Department of Biology, University of Florida, Gainesville, Florida 32611 USA
3. Department of Integrative Biology, University of California, Berkeley, California 94720 USA
4. Department of Forest Resources, University of Minnesota, St. Paul, Minnesota 55108 USA
5. Department of Biological Sciences, Macquarie University, Sydney, New South Wales 2109 Australia
6. Department of Biological Sciences, New Jersey Institute of Technology, Newark, New Jersey 07102 USA
7. Department of Plant Biology, University of Illinois, Champaign-Urbana, Illinois 61801 USA
8. Instituto Multidisciplinario de Biología Vegetal, Consejo Nacional de Investigaciones Científicas y Técnicas and Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba, Casilla de Correo 495, 5000 Córdoba, Argentina
9. Department of Plant Ecology, University of Bayreuth, 95440 Bayreuth, Germany
10. Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803 USA
11. Department of Ecology and Evolutionary Biology, University of California, Los Angeles, California 90095 USA
12. Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, Minnesota 55108 USA
13. Department of Biology, McGill University, 1205 Dr. Penfield Avenue, Montreal, Quebec H3A 1B1 Canada
14. Santa Fe Botanical Garden, P.O. Box 23343, Santa Fe, New Mexico 87502-3343 USA
15. Department of Biology, One University Boulevard, University of Missouri, St. Louis, Missouri 63121 USA