The Influences of Species Richness and Climate on the Phylogenetic Structure of African Haplorhine and Strepsirrhine Primate Communities

Abstract

Many factors contribute to the structure of primate communities, including historical processes, interspecific competition, and climate. Here, we quantify the phylogenetic structure of individual primate communities to evaluate these factors relative to a null model. Then, we examine the effects of species richness and local climate on variation in community phylogenetic structure. We analyze 71 haplorhine and 29 strepsirrhine communities in Africa and quantify their net relatedness (NRI) and nearest taxon (NTI) indices. Significantly low, i.e., phylogenetically even, NRI and NTI values are indicative of interspecific competition in the past, resulting in closely related species not being found in the same community. In contrast, significantly high, i.e., phylogenetically clustered, NRI and NTI values suggest that closely related species have similar ecological requirements, resulting in closely related species occupying the same community. In a second set of analyses, we used simultaneous autoregressive models to examine if species richness, rainfall, and temperature predict variation in community phylogenetic structure. Most individual communities exhibited phyloge- netically random species assemblages. However, significantly structured haplorhine