EAGER: Ancestral reconstruction of plasticity along environmental gradients: tracing the pathways to ecological specialization

University Of California-Davis, Davis CA

Investigators

Abstract

Ecological specialization is the engine generating biological diversity. But why do species become specialists on a particular resource or set of conditions rather than expand their niches to become more generalized, incorporating both old and new resources? How does the degree to which species are specialized in their ecological niche predict their geographic range and climatic tolerances? Is the ability to tolerate a large range of environmental and resource conditions (i.e., to be a generalist) a trait that is shared over evolutionary time by species? This project uses cutting edge analytical techniques to map the resilience of multiple plant species onto the pattern of their evolutionary relationships. This will allow researchers to explore how species tolerance to environmental change evolves across related species, whether tolerance to a range of experimental environments predicts the degree to which species are specialized in their current ecological niches, and whether current tolerance can predict species' responses to future changes in the climate. This project also advances education and diversity by training underrepresented groups of students. This project combines contemporary (ecological experiments/observations) with historical (phylogenetic) approaches to disentangle intrinsic and extrinsic forces driving ecological specialization. Ancestral trait reconstruction of multivariate parameters describing norms of reactions will be completed on multiple plant species. Fitness, in addition to leaf physiology and other plant traits, will be measured in 18 Streptanthoid species grown in environmental treatments that represent gradients in water availability and leaf herbivory. Once completed this project will help us understand how the evolution of plasticity and competitive response relates to specialization. In addition, new methodological approaches should contribute to the study of these questions in a variety of systems across the tree of life. Graduate students from underrepresented groups will contribute directly to this research.