UC Davis

Aim: To determine how taxonomic level and spatial scale affect the phylogenetic structure of species assemblages across four classes of terrestrial vertebrates. Location: Mainland China. Methods: Using species distribution data from Mammalia, Aves, Reptilia and Amphibia, including 2153 species from 2105 counties and 1632 species from 295 nature reserves across mainland China, we analysed the phylogenetic structure of co-occurring species at multiple taxonomic levels (class, order, family and genus) and spatial scales. Results: We found that phylogenetic clustering and unstructured patterns were more frequent than phylogenetic overdispersion in all groups. There was a higher frequency of phylogenetic clustering within classes and orders than within families and genera, while spatial scale had little effect on the frequency of phylogenetic clustering. Birds and mammals showed less frequent clustering patterns than amphibians and reptiles. Main conclusions: Phylogenetic clustering in terrestrial vertebrates was predominant over overdispersion at regional scales and higher taxonomic levels. Our results suggest that regional ecological and evolutionary factors, such as environmental filtering and speciation relative to extinction or colonization rates, are important in determining species assemblages of animals.