Variation-independent Mechanisms

Variation-independent mechanisms are those that function independently of the presence of variation in space in population densities and environmental factors. They may be affected by the presence of variation, but do not require them for their operation, and in general still function in the presence of spatial variation. A classic example is resource partitioning (Chesson 1991). Naturally, variation-independent mechanisms are to be contrasted with variation-dependent mechanisms.  This distinction was first presented in Chesson (2000).  Note that both varation-dependent and variation-independent mechanisms may well operate together in a given ecological system (Chesson 2000).  The related concepts to do with temporal variation are termed fluctuation-dependent, and fluctuation-independent mechanisms


Chesson, P.L., Case, T.J. 1986.  Nonequilibrium community theories: chance, variability, history, and coexistence. Pp 229-239 in J. Diamond and T. Case, eds, "Community Ecology," Harper and Row

Chesson, P. 2000. Mechanisms of maintenance of species diversity. Annual Review of Ecology and Systematics 31, 343-66.