9600108. HAIRSTON Organisms have a wide range of adaptations to life in a changing environment. Among fish, jaw morphology is often related to diet, which varies between seasons and populations. Linking environmental variation with morphological variation can provide insights into the causes of character variation observed in nature. In research funded by this award, killifish (Cyprinodon variegatus) populations on mangrove islands in Florida Bay will be studied to assess the ways in which temporal and spatial variation in diet produce and maintain differences in jaw shape and size. Environmental variation in food resources and food utilization by populations of killifish inhabiting two distinct habitats (bay and island pools) will be documented. Variation in feeding morphology among these populations will then be assayed to elucidate the environmental and genetic contributions to morphological variation. In a related study, the developmental basis of diet-specific feeding efficiency will be assessed. The research will shed light on a longstanding issue in population biology, how morphological variation is produced and maintained in a changing environment. Because such variation provides the fuel for species to cope with environmental change, the research has implications for conservation biology and habitat management.
