Theoretical and Methodological Issues in Analysis of Density-Dependent Legitimation in Organizational Evolution

Abstract

geometric treatment of the niche. He defined the fundamental niche of a population as the hypervolume formed by the set of points for which the population's growth rate (fitness) is nonnegative. In other words, the fundamental niche consists of the set of all environmental conditions in which the population can grow or at least sustain its numbers. By extension, the fundamental niche of an organizational form consists of the social, economic, and political conditions required to sustain the functioning of organizations that embody the form. The geometric conception of the niche facilitates definition of the intersection of fundamental niches of pairs of populations. If two populations rely on completely different kinds of resources and depend on different kinds of social and political institutions, then their fundamental niches do not intersect. Otherwise, they do intersect, and it makes sense to measure their similarity in terms of the degree of intersection (or overlap, when only one or two environmental dimensions are considered). The concept of intersection of fundamental niches leads naturally to a definition of potential competition: The potential for two populations to compete is proportional to the intersection of their fundamental niches. (This is potential competition because the populations must exist in the same systems to actually compete.) It follows that two populations compete if and only if their fundamental niches intersect. The implied equivalence of niche intersection and competition has played a crucial role in allowing ecologists to relate naturalistic observations on realized niches to dynamic models of population growth and expansion. Hannan and Freeman (1977, 1989) argue that such equivalence can play a similarly central role in empirical analysis and theoretical analysis of organizational dynamics. When populations with intersecting fundamental niches inhabit the same system, potential competition is converted into actual competition. Under such conditions, the expansion of one population changes the conditions of existence of the others. In the case of competition, the presence of the competitor reduces the set (range) of environments in which the other populations can sustain themselves. Hutchinson coined the term realized niche to denote the restricted set of environments in which growth rates are positive in the presence of competitors (a subset of the fundamental niche). Except in the highly unusual case in which a population exists in isolation This content downloaded from 157.55.39.176 on Sat, 09 Apr 2016 06:40:26 UTC All use subject to http://about.jstor.org/terms