Seasonal trade‐off between starvation resistance and cold resistance in temperate wild‐caught Drosophila simulans

Abstract Selection experiments with Drosophila have revealed a possible evolutionary trade‐off between cold resistance and starvation resistance that may be controlled by lipid metabolism. To test this trade‐off in naturally occurring Drosophila simulans populations, flies were simultaneously collected from two temperate locales experiencing contrasting seasons. Flies from a tropical locale served as a control. Cold coma recovery, starvation resistance and lipid proportion were assayed on adult males and females from each locale. Compared with the summer‐collected flies from Canberra, the winter‐collected flies from San Diego recovered from cold coma more quickly, were less starvation resistant and had lower lipid levels. These results support an evolutionary trade‐off between cold resistance and starvation resistance. Combined, these data also suggest that differences in lipid metabolism may be an underlying mechanism for this trade‐off.