Speaker:

Prof. Stephen P. Hubbell

Affiliation:

The University of Georgia

Title:

The Neutral Theory of Biodiversity and Biogeography

Abstract:

The central goal of ecology is to understand the ecological assembly rules of natural communities on local to global scales. Remarkable progress towards this goal has been achieved over the last several decades through primarily reductionistic approaches on small observational and experimental scales. However, significant unanswered theoretical and empirical questions still abound, particularly on large spatial and temporal scales. Classical theory asserts that ecological nature is fundamentally asymmetric by emphasizing the inherent uniqueness of all species in ecological communities (i.e., niche assembly theory). According to this largely deterministic perspective, competing species coexist in closed, stable assemblages by partitioning limiting resources through niche differentiation. However, symmetric neutral theory, in which all species broadly overlap in the use of resources and obey the same ecological interaction rules on a per capita basis, has recently been shown to be qualitatively and quantitatively consistent with a number of major macroecological pattern regularities, many of which have remained unexplained or largely so, by contemporary niche assembly theory. These including patterns of relative species abundance (RSA), species-area relationships, and even phylogeny. According to this largely statistical-mechanical perspective, ecological communities consist of open, nonequilibrium assemblages of species whose presence, absence, and relative abundance are governed by random speciation, dispersal, ecological drift, and extinction. One of the major theoretical challenges to theoretical ecology is to reconcile niche assembly theory and neutral theory. This talk will outline some of the recent results of neutral theory and steps towards a theoretical reconciliation of these two very different perspectives in ecology.


The Seminar Page The Center for Simulational Physics Dep. of Physics and Astronomy The University of Georgia

©Andreas Voigt