Minimal Community Structure: An Explanation of Species Abundance Patterns

Publisher Website
Google Scholar
Abstract
Recent proposals that the canonical lognormal distribution and the resulting species-area constant, z .simeq. 1/4, are artifacts of the general lognormal curve and regression techniques, are inadequate. An alternative hypothesis is suggested which accounts for these regularities in terms of a hierarchical community structure represented by sequentially divided niche space. This hierarchical pattern, which can be considered to be a minimal form of community structure, derives from evolutionary and ecological considerations for generating species diversity and accounts for the observed abundance structures of small ensembles and large natural communities. Niche apportionment between species may involve the random division of more than 1 resource, and an interesting invariance in the pattern of apportionment is observed for assemblages with 3 spp. The possibility that the canonical lognormal distribution is a conceptual artifact resulting from arbitrary systems of classification is considered to be false. Aside from its intutitive appeal, the model presented should be of interest because of offers explanations of 2 ubiquitous patterns in nature: the canonical lognormal and the resulting species-area constant.