The Importance of Demographic Niches to Tree Diversity

Authors

Richard Condit, Smithsonian Tropical Research InstituteFollow
Peter Ashton, Harvard University
Sarayudh Bunyavejchewin, Thai National Park Wildlife and Plant Conservation Department
H. S. Dattaraja, Indian Institute of Science, Bangalore
Stuart J. Davies, Harvard UniversityFollow
Shameema Esufali, University of Peradeniya
Corneille Ewango, University of Missouri - St Louis
Robin Foster, Field Museum
I. A.U.N. Gunatilleke, University of Peradeniya
C. V.S. Gunatilleke, University of Peradeniya
Pamela Hall, Florida State University
Kyle E. Harms, Louisiana State University
Terese Hart, Wildlife Conservation Society, Kinshasa, Democratic Republic of the Congo
Consuelo Hernandez, Pontifícia Universidad Católica de Ecuador
Stephen Hubbell, University of Georgia
Akira Ito, Osaka City University
Somboon Kiratiprayoon, Thammasat University
James LaFrankie, Nanyang Technological University, Singapore
Suzanne Loo de Lao, Smithsonian Tropical Research Institute
Jean-Remy Makana, Wildlife Conservation Society, Kinshasa, Democratic Republic of the Congo
Md. Nur Supardi Noor, Forest Research Institute, Malaysia
Abdul Rahman Kassim, Forest Research Institute, Malaysia
Sabrina E. Russo, University of Nebraska - LincolnFollow
Raman Sukumar, Indian Institute of Science, Bangalore
Cristián Samper, Smithsonian Institution
Hebbalulu S. Suresh, Indian Institute of Science, Bangalore
Sylvester Tan, Sarawak Forest Department
Sean Thomas, University of Toronto
Renato Valencia, Pontifícia Universidad Católica de Ecuador
Martha Vallejo, Instituto Alexander von Humboldt
Gorky Villa, Pontifícia Universidad Católica de Ecuador
Tommaso Zillio, Smithsonian Tropical Research Institute

Document Type

Article

Date of this Version

7-7-2006

Citation

Science (July 7, 2006) 313: 98-101.

Comments

Copyright 2006, AAAS. Used by permission. Online supplemental materials may be accessed at: http://www.sciencemag.org/content/313/5783/98/rel-suppl/cec70a7fe7f3f3ab/suppl/DC1

Abstract

Most ecological hypotheses about species coexistence hinge on species differences, but quantifying trait differences across species in diverse communities is often unfeasible. We examined the variation of demographic traits using a global tropical forest data set covering 4,500 species in 10 large-scale tree inventories. With a hierarchical Bayesian approach, we quantified the distribution of mortality and growth rates of all tree species at each site. This allowed us to test the prediction that demographic differences facilitate species richness, as suggested by the theory that a tradeoff between high growth and high survival allows species to coexist. Contrary to the prediction, the most diverse forests had the least demographic variation. Although demographic differences may foster coexistence, they do not explain any of the 16-fold variation in tree species richness observed across the tropics.