SG: ARTS: Toward a monographic treatment of Calyceraceae: fieldwork, phylogeny, and character evolution

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The foundation of comparative biology rests on the investigation of organismal similarities and differences that are generated through evolutionary processes. One important application of the comparative method in the study of biodiversity is the comparison of sister lineages, groups which are each other's closest relative, that have undergone very different evolutionary histories. By comparing the fates of these lineages, scientists are able to understand why some are successful and others are not. A prominent example is the sunflower family, the Asteraceae, and its less well-known sister family, the Calyceraceae. The Asteraceae has been one of the most successful plant families with over 20,000 species spread throughout the world, including many economically important plants, such as sunflowers, daises, lettuce, artichokes and dandelions. The evolution of the Calyceraceae on the other hand has resulted in only 56 species, all found in southern South America. Despite the large number of species, Asteraceae researchers are developing an understanding of the family?s evolutionary trajectory and traits, however little is known about the Calyceraceae. This research project will develop an understanding of what the common ancestor of these two families was like. This will allow a careful analysis of which changes allowed the Asteraceae to succeed in generating great diversity, including developing economically important traits, and which inhibited Calyceraceae diversification. This project will foster interactions among scientists, graduate, and undergraduate students in two countries, thus enhancing international collaboration and cultural awareness. Field work will be undertaken in collaboration with researchers in Argentina to collect the 56 species of the Calyceraceae. This material will be used to generate a molecular phylogeny and a morphological trait matrix. Comparative DNA sequencing of both chloroplast and nuclear genes will be undertaken to infer phylogenetic relationships in the family. Additionally a morphological trait matrix, of important flower and fruit characteristics, will be generated and analyzed in conjunction with the phylogeny to study the evolution of character states in the Calyceraceae. This data on the Calyceraceae will complement the knowledge already available for the Asteraceae allowing for addressing powerful comparative biology questions. What are the phylogenetic relationships among all species of Calyceraceae? What are the ancestral floral and fruit character traits states in Calyceraceae and how do these relate to those in the Asteraceae? The final products of the research include bilingual taxonomic revision, including dichotomous and polyclave keys, which will be made available in both print and electronic versions. To increase participation by underrepresented groups, students will be recruited via Brigham Young University's Multicultural Student Center. Guest presentations and lab exercises covering state-core competencies will be developed with two area high school instructors. A rotating display will also be developed, using age-appropriate materials, for the BYU Life Science Museum, which is heavily visited by K-12 students.