Systematics of sedges (Cyperaceae)

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Systematics is the science that names, classifies and determines the evolutionary relationships of living things. Whether we are developing environmental policy, making conservation decisions, or studying the ecology or molecular biology of a species, systematics is essential because it defines the units (species, families, etc.) and provides the context (evolutionary relationships) for meaningful comparisons in biology. My research focuses on the systematics of the sedge family (Cyperaceae), a truly remarkable group of plants characterized by their exceptional diversity (ca. 5000 species), varied habitats (deserts to rain forests), unusual cytology (chromosome numbers from 12 to 112) and diverse biogeographical patterns. In the Flora of North America region (Canada & USA), sedges represent nearly 4% of our native flora (10% in Canada); they are common to every floral region, and they dominate vast areas of the continent in terms of diversity and biomass. Moreover, approximately 10% of sedges are of either direct (medicines, crops) or indirect (weeds) economic importance to humanity. Nevertheless, sedges remain a poorly studied group whose classification and relationships are highly unresolved. My long-term research objectives in the sedge family are to discover diversity, to clarify relationships, and to produce predictive classifications that can be used to preserve biodiversity and to advance our knowledge of sedge biology. In order to forward these long-term goals, my research will focus on three short-term research objectives: (1) to define, circumscribe and determine the evolutionary relationships of the major groups within Cyperaceae and (2) tribe Cariceae, and (3) to produce a revised classification of Carex section Lupulinae. The wider impact of this research ranges from preserving biodiversity, to an improved understanding of world biogeography, C3/C4 photosynthesis and the evolution of chromosomal variation in sedges.