CAREER: The Geography of Biocomplexity: Cultivar Diversity and Agricultural Plasticity in Fungus-Growing Ants

University Of Texas At Austin, Austin TX

Investigators

Abstract

9983879 Mueller Fungus-growing ants comprise a group of about 200 species, all obligately dependent on the cultivation of fungus for food. Fungal cultivation by ants involves complex manuring regimes and use of antibiotic "herbicides" to control alien fungi and garden parasites. Recent genetic analyses indicate that fungus-growing ants domesticated fungal cultivars multiple times during their evolutionary history and frequently exchange these cultivars between ant species. The evolutionary ecology of cultivar exchange between ants will be investigated by testing a series of hypotheses on the ecological factors that govern exchanges. Field experiments will be conducted in Panama and the southwestern US, complemented by genetic analyses of the diversity of ants, their cultivars, and associated pathogens. Model ant-fungus systems will be developed to test specific hypotheses on the evolutionary and ecological relationships between ant farmers, their cultivars, associated garden parasites, and the ecological conditions modulating these relationships. The attine ant-fungus symbiosis represents a unique case of evolutionary and ecological complexity. This complexity derives from the interaction of pathogenic and mutualistic microbes that evolved to form integrated parts of the ecological fabric of a social animal, the ant farmers. The research will yield a synthetic understanding of this 50-million-year antfarmer-cultivar association.