Genetic change is a dominant theme in the evolutiona and diversification of organisms, yet surprisingly little is known about which traits and organisms are most likely to undergo major shifts in gene frequency in response to natural selection and environmental change. Empirical study of change in heritable traits depends on having an operational measure of potential change that reflects the ability of a trait to respond to a given external selection pressure under the constraint of stabilizing or opposing selection on correlated characters. The investigators suggest that the additive genetic variance conditioned on correlated traits and scaled by the square of the trait mean, "conditional IA," is a better measure of short-term change than the traditional measure, "heritability." They will use these new measures to test hypotheses about the role of genetic constraints in determining large-scale patterns of variation in the blossoms of Dalechampia, a neotropical vine. They will use a combination of artificial-selection and field experiments to document potential for evolution and patterns of natural selection.
This project will advance our understanding of how organisms evolve in response to natural selection, with possible applications to understanding response of plants to climate change, crop breeding, and the origins of pesticide and drug resistance. The project will train two postdoctoral researchers, one master's student, and several undergraduate students. It will also promote international collaboration between the USA, Norway, the United Kingdom, and several Latin American countries.
