Using Manipulated Phenotypes to Evaluate the Contribution of Maternal Effects to Life History Evolution in an Herbaceous Plant

University Of Virginia Main Campus, Charlottesville VA

Investigators

Abstract

The contribution of parents to their offspring often extends beyond genes. For example, maternal body size and nutritional condition influences offspring trait expression in many species. Although such maternal effects have been widely documented, the extent to which they influence evolution in natural populations is not known. This research will use the herbaceous plant Campanula americana as a model system to (1) evaluate a mechanistic model of maternal effects in a natural population, and to (2) fit a quantitative genetic model to determine the importance of maternal effects for evolution. Artificial selection and controlled growth environments will be used to create genetic and environmentally based changes in the expression of maternal traits. The consequences of these manipulations for offspring trait expression will be evaluated under natural conditions and associated with offspring success. Theory predicts that maternal effects may cause delayed, negative or cyclical responses to selection. Understanding the importance of these intergenerational effects through empirical studies and fitting genetic models will enable more accurate predictions of evolutionary response to natural and man-made changes in the environment. Such predictive models are necessary for evolutionary biology to contribute to conservation, epidemiological, and agricultural challenges. The project will also provide training opportunities to postdoctoral and undergraduate researchers.