9505941 Becerra This award is under the North American Research Fellows Program, which enables U.S. scientists and engineers from the United States, Canada and Mexico, to visit research establishments in one or both of the other two countries for periods of three to twelve months. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twelve month postdoctoral research visit by Dr. Judith X. Becerra to work with Dr. Daniel Pinero at Ciudad Universitaria (UNAM) in Mexico. A second year of support will be provided by the Postdoctoral and Junior Investigator Research Fellows Program, to work with Dr. Michael Hammer at the University of Arizona. This research will involve comparison of DNA phylogeny of the chrysomelid genus Blepharida with the evolution of chemical and morphological traits of its host, the genus Bursera. The PI will also determine whether adaptive traits in plants and insects have evolved under each other's evolution by testing whether the ages of the associated clades of plants and insects are equivalent. The U.S. portion of the award will be spent estimating the probable dates of origin of species of Bursera and Blepharida by calculating the rates of nucleotide substitution in the ITS (Internal Transcribed Spacer) sequences obtained, following the molecular clock hypothesis. This research will provide the first evaluation of the significance of plant defensive chemical compounds, defensive plant morphology, and counterdefensive insect morphology and behavior, for the evolution of host exploitation by phytophagous insects. ***
