Doctoral Dissertation Improvement Grant: Fuel Use and Metabolic Architecture in the Hawkmoth Amphion Floridensis

9520626飞虫使用不同的代谢燃料来支持能量昂贵的飞行。苍蝇和蜜蜂通常使用糖来为飞行提供燃料，而飞蛾和蝴蝶通常使用脂肪储存。这项研究将在几个层面上检查飞蛾的代谢生理，这些飞蛾的身体很重，翅膀很窄，飞行速度很快，飞行成本很高。在飞行过程中测量氧气消耗率和二氧化碳产生率将表明糖或脂肪是否被氧化。食用了富含糖分的花蜜的飞蛾将与未食用的飞蛾进行比较，以确定燃料的使用是否因营养状况而异。在飞行肌肉的碳水化合物和脂质燃烧途径中，分解代谢酶的最大反应速率将被测定，以确定进食和飞行性能如何与飞蛾的潜在代谢生物化学相关。稳定同位素分析将用于描述幼虫和成虫获得的资源对卵子供应的贡献。该研究将提高对活动代谢的限制以及代谢能力和燃料可用性在限制性能中的相对重要性的理解。对飞行和繁殖之间能量分配方式的更好理解可能会增加我们对飞行昆虫种群动态的理解。

9520626 Flying insects vary in the metabolic fuels they use to support energetically costly flight. Flies and bees usually use sugars to fuel flight, while moths and butterflies usually use fat stores. This research will examine metabolic physiology at several levels in a hawkmoth whose heavy body, narrow wings and rapid flight impose high flight costs. Measurement of rates of oxygen consumption and carbon dioxide production during flight will indicate whether sugars or fats are being oxidized. Moths that have fed on sugar-rich nectar will be compared with unfed moths to determine whether fuel use varies with nutritional status. Maximum reaction rates of catabolic enzymes in the carbohydrate and lipid burning pathways of flight muscle will be assayed to determine how feeding and flight performance relate to the moth's underlying metabolic biochemistry. Stable isotope analysis will be used to characterize the contribution of larvally-obtained and adult- obtained resources to egg provisioning. The research will improve understanding of the constraints on activity metabolism and the relative importance of metabolic capacity and fuel availability in limiting performance. Improved understanding of the way energy is allocated between flight and reproduction may increase our understanding of the population dynamics of flying insects.