My research focuses on speciation and phylogeny of flowering plants, particularly the legume family. I am currently working on several interrelated projects in the mimosoid legumes. The first is a study of three genera in the Dichrostachys group. This group has radiated widely throughout Madagascar, with all but three of approximately 30 species endemic to the island. The group provides a model system for investigating the evolution of Malagasy plants both because there are a large number of species and because they are widely distributed throughout the dry, seasonally dry, and moist forests of Madagascar. This study integrates morphological, developmental, molecular, pollination, and distribution data from the Dichrostachys group to address fundamental questions about the diversification of this unique island biota. I have also initiated a higher level study, working with Australian and American scientists to put together a phylogeny of all mimosoid legumes, using both morphological and molecular characters. Thus far we have produced a molecular phylogeny based on four chloroplast genes and are currently working on parallel data sets using other genes and morphological data. These data have been pivotal in demonstrating that the tribes do not form natural groups and that the large genus Acacia must be broken up into 3-5 genera. I am also producing monographic treatments of mimosoid genera, with descriptions and keys for identification. My work is an important component of the study of biodiversity and provides baseline data about our rapidly disappearing biota. A phylogenetic context is indispensable to the agricultural evaluation and development of mimosoid legumes. Reliable identification keys to the genera, with comprehensive descriptions, will be widely used by taxonomists, foresters, plant breeders, and ecologists.