ABSTRACT
This paper reviews the progress in documenting and understanding species richness for one of the most diverse and economically important groups of plants (the grasses; Poaceae). It discusses the value of modern taxonomic resources and large phylogenetic trees for macro-evolutionary studies. More specifically, it discusses the use of phylogenetic trees for detecting and dating major lineages, investigating biogeographical origins, identifying patterns of diversification and investigating factors leading to species richness. Theoretical and practical issues regarding the production of large phylogenetic trees and supertrees of the grass family (c. 650 genera and 10,000 species) are also discussed. It asks how far we are from complete tribal, generic and species phylogenetic trees of the grasses.
