Biodiversity loss is of major concern to human societies and is a complex scientific problem. Many studies have concentrated on the dynamics of species richness (number of species), but fewer have explored the dynamics of species evenness, which takes into account the numerical dominance of different species. This is despite the fact that evenness and dominance relate more directly to ecosystem function and are more sensitive to human impacts.
We have just published a study in the Journal of Theoretical Biology in which we develop new mathematical formulae that succinctly describe the dominance and evenness of ecological communities for typical species-abundance distributions (SADs). We use the formulae to (i) infer that dominance is expected to be typically high in natural communities, (ii) show how a lower bound of dominance can be estimated for the Amazonian tree community, and (iii) predict that dominance increases with increased environmental variance, which could arise in future, for example, due to human impacts.
Analytical formulae for computing dominance from species-abundance distributions
Tak Fung, Laura Villain, Ryan A. Chisholm