This study investigates the genetics underlying character variation among individuals within a population, and how the genetic structure of species evolves. Because characters are affected by many genes, and because genes affect many characters, variation in different characters (e.g., arm length and leg length) are not independent of each other. The genetic variance-covariance matrix (G-matrix) summarizes these interdependencies. This study will estimate the G-matrix for eight species of Anolis lizards. Because species of these lizards on different islands have adapted to the same environment, this study will allow the comparison of distantly related species that have experienced the same natural selection pressures, as well as closely related species that live on the same island, but have experienced different selective pressures. These comparisons will permit evaluation of the factors that affect how the G-matrix evolves.
The G-matrix is of fundamental importance in describing evolutionary change by translating natural selection in one generation into phenotypic change in the next. Nonetheless, scientists still do not have a good understanding of what factors affect evolution of the G-matrix. By examining many species, this study will be the most extensive study to date and will thus greatly expand understanding of the genetics underlying evolutionary change. This project will support the training of a postdoctoral scholar, a graduate student, and several undergraduates, including students from traditionally underrepresented groups. Anolis lizards have become one of the major models for studying evolutionary diversification and relaying that understanding to a broad audience. Accounts of Anolis evolution have appeared in countless textbooks, television programs and popular publications. This project will continue those efforts.
