Inferring species interactions in tropical forests
- aDepartment of Physics, 104 Davey Laboratory, Pennsylvania State University, University Park, PA 16802;
- bDepartment of Biology, Muller Laboratory, Pennsylvania State University, University Park, PA 16802;
- cDepartment of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095;
- dThe Smithsonian Tropical Research Institute, P.O. Box 0843-03092, Balboa, Ancón Panama, Republic of Panama;
- eDipartimento di Fisica “G. Galilei,” Università di Padova, Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, Istituto Nazionale di Fisica Nucleare, Via Marzolo 8, 35131 Padua, Italy
Abstract
We present 2 distinct and independent approaches to deduce the effective interaction strengths between species and apply it to the 20 most abundant species in the long-term 50-ha plot on Barro Colorado Island, Panama. The first approach employs the principle of maximum entropy, and the second uses a stochastic birth–death model. Both approaches yield very similar answers and show that the collective effects of the pairwise interspecific interaction strengths are weak compared with the intraspecific interactions. Our approaches can be applied to other ecological communities in steady state to evaluate the extent to which interactions need to be incorporated into theoretical explanations for their structure and dynamics.
Footnotes
- 1 To whom correspondence may be addressed. E-mail: jayanth{at}phys.psu.edu or amos.maritan{at}pd.infn.it
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Edited by James H. Brown, University of New Mexico, Albuquerque, NM, and approved May 29, 2009
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Author contributions: I.V., J.R.B., S.P.H., and A.M. designed research, performed research, contributed new reagents/analytic tools, analyzed data, and wrote the paper.
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The authors declare no conflict of interest.
