Systematic revisions of global taxa are plagued by the difficulties of inspecting material from wide-ranging field sites and museum collections, coordinating efforts across continents and time zones, and rectifying regional and global taxonomic concepts. Yet revisions of global taxa provide essential information for understanding diversification patterns and providing a roadmap for biodiversity preservation . Providing a subgeneric revisionary framework for tackling cosmopolitan taxa demands a global integration of taxonomic training, specimen collection, data acquisition, and data analysis. Using this revisionary framework to enable future studies in the taxon demands creation of a robust collaborative framework that will grow with the data and the collaborative team.
In this project, we are launching an integrated set of global research and education activities that broaden taxonomic expertise across a wide range of skill levels and strengthen the global taxonomic community. We are leveraging decades of fieldwork and collaboration-building to undertake a global sectional revision of the sedge genus Carex and the embedded genera of tribe Cariceae (in Family Cyperaceae). Carex is among the four largest flowering plant genera worldwide [3, 4] and has not been revised globally since 1909 . Sectional classification is the usual gateway into species identification in Carex, and researchers typically circumscribe Carex research projects according to sections. Despite this fact, sectional classification has evolved more or less independently in different regions of the world, with the result that many taxa are assigned to conflicting sections in different taxonomic treatments or to no section at all. A revised sectional classification would greatly facilitate both conservation of and research on the genus. Our specific themes / goals are:
1. Research Community and Tools: Create a virtual research environment for the Cyperaceae community. A key component of this project is enhancement of the functionality of a Virtual Research Environment (VRE; [6, 7]) that we have established for the Cyperaceae research community (http://cyperaceae.e-monocot.org/). In the proposed project, we will collaborate with ViBRANT / Scratchpads developers and eMonocot to expand the functionality of the Cyperaceae Scratchpad, creating new data structures and a framework for online collaboration in assembling DNA sequence data, snapshots of our growing phylogenetic work, and taxon descriptions at the species and sectional level. Our platform for collaborating on the revision of Carex will thus enhance the informatic toolset for the entire community.
2. Molecular Phylogeny: Create a phylogenetic framework for Carex. Our primary goal is to develop a species-level phylogeny for Carex and identify major lineages that we can use as a framework in revising the sectional classification. To date the most comprehensive published analysis of Cariceae taxa has been a single-gene analysis of ca. 550 species , which represents only approximately 25% of the genus. The senior personnel and PIs on this proposal currently have on hand more than 3,400 DNA extractions representing 930 accepted Cariceae taxa. Our sampling plans for this project include five coordinated field-collecting trips and will bring us to an estimated 1,360 species in a hierarchical sampling of 3-10 genes, including two angiosperm DNA barcoding regions already sequenced for hundreds of individuals in the group to provide a globally useful genetic resource.
3. Traits and Diversification: Assemble a database of traits to test diversification patterns and form the basis for predictive classification and monography. There has been very little work to date on the ecological, morphological, and biogeographic dimensions of broad-scale diversification in Carex (e.g., [1, 8-11]). In this study, we will be gathering estimates of climatic niche for all species for which specimen data are available, geographic distributions based on specimen data and published reports, and morphological data measured from herbarium specimens for three focal clades. These will allow us to investigate how rates of morphological and ecological diversification correlate with rates of lineage diversification, convergence and divergence in traits and climatic niche, and the effects of biogeography on lineage and trait diversification. These fundamental questions about the origins of biodiversity also provide insight into ecological and biogeographic relevance of the classification we are developing.
4. Taxonomic Synthesis: Revise the sectional classification of Carex. A robust phylogeny of the genus is only half of the sectional revision; the other half is identifying synapomorphies that define lineages, and assigning valid names to those lineages. We will be conducting two in-person synthesis meetings and several meetings via webconferencing to bring together late-career and junior sedge taxonomists from around the world to critically study the phylogeny and erect a novel classification. In addition, we are utilizing the “Taxon description” data type in the Cyperaceae Scratchpad as a species-level trait database, which we are populateing from floras and monographs to both publish species descriptions and summarize morphological traits of the clades we identify. This stage of the work will result in at least two synthesis papers—one on classification and higher-level nomenclature, one on phylogeny—that we will be publishing under the authorship of “Cariceae Working Group,” as well as disseminating via the Cyperaceae Scratchpad.
In addition, we are increasing taxonomic capacity through our broader impacts: training the next generation of systematists, increasing taxonomic readiness in pre-college and undergraduate students, transferring sedge information to broad audiences, and strengthening informatic and genetic taxonomic resources. This training and research infrastructure at a global scale, in a genus of global significance, will overcome a major hurdle to our understanding of the biodiversity of global taxa: the difficulty of getting the cognizant researchers together with interested students on a regular basis and in a collaborative framework to both translate their lifelong knowledge of the taxonomy and make significant taxonomic strides as a research group.