We propose to use the Daltoniaceae (Bryopsida: Hookeriales) as a vehicle for training in systematics, for investigating an important component of tropical and Southern Hemisphere bryophyte biodiversity, and for addressing general questions about diversification processes in these organisms.  Previous and ongoing research at Duke (see above), on the pleurocarpous mosses in general and on the Hookeriales in particular, provides a critical phylogenetic context for the current project.  We have demonstrated that the Daltoniaceae comprise a monophyletic group, and we have reconstructed the evolution of selected morphological characters across the broader Hookeriales.  These data provide a solid foundation for more intensive research on the Daltoniaceae.  Moreover, the collaboration between Shaw and Buck is especially strong for providing a well-rounded training experience for participants.  Duke has a thriving program in plant systematics that includes five facult and over 30 students and post-docs.  Buck has an active research program focusing on floristic analyses, and has extensive experience with the Hookeriales and other pleurocarpous mosses.  Both of us have experience doing taxonomic monographs. Herbarium facilities for monographic research and training at the New York Botanical Garden are unsurpassed.  Both Duke and NY have outstanding moss collections and both are actively engaged in databasing our specimens. Our collaboration is well-established and several papers that integrate morphological and molecular approaches to systematics have resulted from our previous work (Buck et al. 2000, 2002, 2004; Shaw et al. 2003; Cox et al. 2004).  We submit that this collaboration permits us to offer participants a unique experience that combines molecular phylogenetic, evolutionary, and taxonomic training that cannot be attained elsewhere, no matter how strong a particular program is in one of these aspects of modern systematics.  Undergraduates will also be involved in the project such that the holistic university environment will prepare our graduate and post-doctoral trainees for academic careers in both the classroom and laboratory.