Published: March 14, 2016

Nancy Emery, Assistant professor in EBIO has just been awarded her NSF career grant. Congratulations Nancy!

Below is the synopsis of the grant award:


Dispersal influences species distribution patterns by determining the range of environments that are colonized and the patterns of gene flow that connect populations. The traits that influence the tendency for an organism to disperse, and the distance it will travel, are often variable within species, heritable, and responsive to selection. Nonetheless, the dominant framework for the evolution of local adaptation, habitat specialization, and species' distribution patterns treats dispersal as a fixed parameter that does not vary among individuals or evolve through time. Moreover, there are few empirical measures of selection on dispersal in response to habitat characteristics, making it impossible to predict the coupled evolutionary dynamics between dispersal traits and species' distribution patterns. The objective of this proposal is to determine how dispersal evolves in response to spatial and temporal variation in an organism's habitat, using experimental and modeling approaches, and grounded in a natural model system that offers a unique opportunity to link theoretical predictions and empirical results. Furthermore, this research will be integrated with education and outreach activities to provide students of diverse backgrounds with authentic research experiences. Collectively, the proposed work will address the following aims:

                1) Identify the functional traits that determine seed dispersal patterns in species that occupy different habitat types. The plant and fruit traits that determine seed dispersal patterns will be characterized in wind tunnels, and compared among species and populations that occupy environments with different habitat characteristics.

                2) Evaluate the evolution of dispersal phenotypes in response to habitat characteristics. Field and greenhouse experiments will evaluate the effects of habitat characteristics on the fitness consequences of dispersal and expression of dispersal phenotypes. Spatially explicit models will be developed to provide a general analysis of how spatial and temporal variation in habitat availability influences the evolution of dispersal propensity and distance.

                3) Provide authentic research experiences for students of diverse ages and backgrounds. Academic-year and summer programs will be developed to provide numerous students with opportunities to directly contribute to the proposed research.



This research will test outstanding hypotheses about the ecological and evolutionary drivers of dispersal traits in an empirically tractable system with properties that mirror the scenarios in many theoretical models, providing a unique opportunity to form a tight link between theoretical predictions and empirical results. The proposed studies will advance knowledge along many fronts in dispersal biology, ecology, and evolutionary biology, by providing (i) a novel analysis of dispersal functional traits in wind-dispersed plants using wind tunnels; (ii) direct measures of the fitness consequences of dispersal in the field; (iii) insights into how multiple environmental drivers interact to influence the expression of dispersal trait plasticity, and (iv) a general model that investigates the effects of how spatial and temporal variation in habitat on the evolution of dispersal. Collectively, the proposed aims are transformative because they will establish a new framework for characterizing gene flow as a parameter that varies among individuals and evolves in concert with habitat specialization and species distribution patterns.



The proposed research will be integrated into course-based research experiences for undergraduate and high school students using approaches that are known to increase student interest, confidence, and persistence in STEM disciplines. This work will also provide support and training for numerous graduate, undergraduate, and high school students with diverse backgrounds and interests, and promote interdisciplinary collaborations between evolutionary biologists and biomechanical engineers. This work will also contribute to the development of a bilingual, field-based education program for elementary schools. Results will be communicated to the general public through guided tours that take place at the primary field site, and shared with agencies and organizations involved in the conservation, management and creation of vernal pool habitat.