9318279 Jansen The phylogeny or genealogical tree for a group of organisms provides the framework for investigating all other aspects of their biology: direction and degree of change in morphological features, physiological adaptations, historical biogeography, modes of speciation, and coevolution with ecologically associated organisms. Dr. Robert Jansen of the University of Texas is studying the phylogeny of the sunflower family of plants, the Asteraceae, and in particular the basal lineages of Mutisioid taxa with emphasis on acquiring new molecular data from chloroplast and nuclear DNA. Between 80 and 120 genera, mostly from the southern hemisphere, are to be sampled, and the molecular data will be complemented with traditional morphological data as well as new characters from the study of pollen and anthers. Chloroplast DNA data, much of it from Dr. Jansen's laboratory over the last several years, have revolutionized the study of phylogeny in the Asteraceae, and the addition of nuclear DNA data and their integration with morphological characters should lead to a rigorous phylogeny for this large and ecologically important family of flowering plants. The Asteraceae, the largest family of dicots in the world, are phylogenetically well studied, due in large part to efforts by Dr. Robert Jansen to apply modern molecular methods of DNA analysis to these plants. Additional research will add data from nuclear genes and also integrate these data with accumulating knowledge of morphology, both traditional taxonomic features and new characters from pollen and anther studies.
