This project will elucidate the nature and basis of social interactions in a model organism, the amoeba Dictyostelium discoideum. These normally single-celled amoebas come together to form a multicellular fruiting body. Most individuals in the fruiting body reproduce through formation of spores, but 20% die to form a stalk that helps disperse the spores. There is both cooperation and conflict over which cells get to become spores. This project will advance understanding of what keeps this conflict from destroying cooperation. D. discoideum is uniquely suitable as a model system to study cooperation and conflict at the molecular level. Genome sequences of many individuals will be analyzed to test the hypothesis that conflicts cause strong selection that molds the molecular variation that underlies the diversity of living species.
Many molecular and genetic resources are available for D. discoideum, whose genome includes many genes similar to human genes and is small enough for whole-genome sequencing. The insights gained from this model system will help us understand cooperation and conflict in obvious social animals such as bees, wolves, and humans, and also in single-celled organisms, including many that cause disease. D. discoideum thrives in the lab and has a short generation time, creating diverse excellent opportunities for students at all levels to participate in research-based learning. This project will provide educational opportunities to high school students through direct collaboration with one high school and development of materials for use by others, to grade school teachers, and to university students through provision of web-accessible novel educational materials. Dissemination of results will include articles for the lay public and general scientific readership, as well as publications for teachers.