Diversification in a clade is often associated with increases in distribution range, increases in the species richness, and /or morphological diversification. It is the aim of this project to incorporate these processes in a general model for plant diversification through investigation of the grass subfamily Danthonioideae, which is particularly suited for this, as species of the subfamily are found on all of the southern continents. Furthermore the species-level taxonomy of the subfamily had been largely resolved in a series of earlier investigations. We resolved the phylogeny of the subfamily to species level, including more than 80% of the species in the analysis. This was not a simple task, as we found incongruence between the phylogenetic histories of the chloroplast and the nuclear genome, which is indicative of hybridization. Based on the phylogeny we updated the generic classification of the subfamily, and established the systematics of the group on a very sound footing. We were able to show that loss of the unique triple-awn system resulted in reductions in the diversification rate, so showing indirectly that the awn-structure is probably in part responsible for the species richness of the group. We were also able to show that the unusual leaf structure of the New Zealand species is most likely the result of the absence of mammalian grazers on the archipelago in the pre-human times. We have research results (not yet published) which link ecological diversification to the available habitats on the differentl continents, that use the group to show the patterns of extreme long distance dispersal in the Southern Hemisphere, and that link taxonomic diversification rates to the continent-specific climatic histories. A monograph of the subfamily is under preparation.