The beaksedges (ca. 375 spp. in tribe Rhynchosporeae; Cyperaceae) are ideal for understanding patterns of diversity and diversification in the three American centers of subtropical/tropical grasslands and savanna because they are one of the most diverse groups in each area. For example, Rhynchospora has the greatest number of taxa (49) endemic to the SE North American Coastal Plain of any plant genus. This study will use 'anchored phylogenomics' (identifying and sequencing 100s or 1000s of highly conserved anchor regions flanked by more variable regions scattered throughout the genome) to produce a robust phylogeny for ca. 100 beaksedge species that will be used to the timing of diversification of the group and the evolution of fruit morphology, habitat specificity, and C3/C4 photosynthesis.
The project will generate a 'toolkit' for anchored phylogenomics in the monocots, a group of 65,000 species that provides the great majority of the human diet (e.g., rice, maize, and wheat). Better knowledge of the relationships among these crop plants and their wild relatives is useful in crop improvement. The project will also enable more precise identifications of beaksedge species, which are often only identified to genus in ecological and conservation studies because of difficulties in identification. This is especially significant because 81 beaksedge species are recognized as wetland indicators in the United States and under-representation of the tribe's diversity reduces the accuracy of conservation assessments and makes the study of some ecological interactions impossible. The project will also train a graduate student in phylogenomics, which is emerging as an increasingly important skill set in systematics, biogeography, ecology, and evolution.
