Manipulating phylogenetic diversity in seed mixes affects community assembly in a tallgrass prairie

Experimentally manipulating phylogenetic diversity offers the opportunity to disentangle evolutionary and environmental constraints on community assembly. We sowed subordinate species mixtures of equal species richness that were either phylogenetically clustered, random, or over-dispersed in a grassland restoration. Three indices of diversity showed contrasting patterns with taxonomic diversity declining, phylogenetic diversity reflecting the sowing pattern, and variable functional trait diversity. Few functional traits measured had a significant phylogenetic signal. We conclude that phylogenetic diversity may initially drive community assembly, but these effects may be transient.