Nixon, Kevin C

Cornell Faculty Member
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I have diverse research interests in the theory and practice of plant systematics. My taxonomic interests include higher level analysis of seed plant and angiosperm relationships, and relationships of Hamamamelid and Rosid ordinal and family relationships. I work at the generic and species level within Fagaceae, and in particular in Quercus. I anticipate completion of the taxonomic treatment for Quercus for Flora Mesoamaricana this summer (2003). I am also very much involved in paleobotanical studies of Tertiary Fagaceae and a wide assortment of Late Cretaceous angiosperm floral remains in collaboration with Dr. W.L. Crepet. We are attempting to place a diverse Cretaceous flora into phylogenetic context and anticipate a rather extensive body of research in this area over the next few years. I also recently have developed a collaboration with Dr. David Dilcher (University of Florida) on early Cretaceous angiosperms of China, resulting in a publication in Science in 2002 describing what appears to be one of the first flowering plants. My theoretical interests center on methods of phylogenetic analysis, computer programs for analysis and display of phylogenetic trees, molecular and morphological information, supertree construction, molecular sequence alignment. I am also working on theory of diagnostic analysis, molecular diagnostics, and development of interactive morphological keys. My recent work has focused on developing algorithms for rapid parsimony analysis (although these can also be applied to maximum likelihood). I am currently working on new methods for faster DNA sequence alignment that should solve some existing problems that are limited by computation time. I have written several software packages, including CLADOS, DADA, Winclada, and Encino, that are used to analyze character distributions and augment other phylogenetic software such as NONA and Hennig86. I am coauthor of a new software package, TNT, with Pablo Goloboff and James S. Farris, that provides tools for rapid phylogenetic analysis of very large data matrices. In the area of biodiversity, I have developed a simple method for measuring phylogenetic diversity and thus maximizing sample diversity based on phylogenetic information. This method will be expanded and directly implemented in upcoming software that will provide priority lists for sampling while undertaking biological prospecting. I am also actively involved in both theoretical and practical approaches to bioprospecting. Finally, I have developed an extensive website system (, that serves images of plants and animals, provides diagnostic interactive keys, and links all of these with specimen data, phylogenetic trees and classifications. The diagnostic programs I have developed run on desktops, handhelds, and through the web interface and are based on new algorithms for maximizing information retrieval.

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