96th ESA Annual Meeting (August 7 -- 12, 2011)

COS 75-7 - Theoretical models of forest communities: Neutral theory plus

Wednesday, August 10, 2011: 3:40 PM
9AB, Austin Convention Center
Ryan A. Chisholm, Department of Biological Sciences, National University of Singapore, Singapore, Singapore
Background/Question/Methods

Patterns of biodiversity are shaped by four fundamental processes:
selection, drift, speciation and dispersal.  The classic spatially
implicit neutral model includes only drift, speciation and some
aspects of dispersal, but nevertheless makes accurate predictions on
some spatial and temporal scales.  A key research goal is to build
upon this simple model by fully incorporating dispersal and selection.
 We present some ongoing work towards this end, with applications to
data from tropical forest tree communities.

Results/Conclusions

Firstly, we investigate how a rigorous treatment of dispersal, using spatially
explicit techniques from statistical field theory, changes the form of
the species abundance distribution.  Secondly, we investigate how the
introduction of selective processes (niche structure) into the model
can improve predictions of dynamic patterns, such as fluctuations in
tree species abundances in tropical forest plots.  This work moves us
towards a model of biodiversity that is more comprehensive than the
spatially implicit neutral model, in terms of the mechanisms it
includes, but yet retains the neutral model’s parsimony and analytical
tractability.  Such a model will be a boon for our scientific
understanding of biodiversity and our attempts to conserve it.