Because of the correlation expected between the phylogenetic relatedness of two taxa and
their net ecological similarity, a measure of the overall phylogenetic relatedness of a
community of interacting organisms can be used to investigate the contemporary ecological
processes that structure community composition. I describe two indices that use the number
of nodes that separate taxa on a phylogeny as a measure of their phylogenetic relatedness.
As an example of the use of these indices in community analysis, I compared the mean …