Abstract：
Endothermic, flying insects are capable of some of the highest recorded metabolic rates. This high aerobic demand is made possible by the insect\'s tracheal system, which supplies the flight muscles with oxygen. Many studies focus on metabolic responses to acute changes in oxygen to test the limits of the insect flight metabolic system, with some flying insects exhibiting oxygen limitation in flight metabolism. These acute studies do not account for possible changes induced by developmental phenotypic plasticity in response to chronic changes in oxygen levels. The endothermic moth Manduca sexta is a model organism that is easy to raise and exhibits a high thorax temperature during flight (∼40°C). In this study, we examined the effects of developmental oxygen exposure during the larval, pupal and adult stages on the adult moth\'s aerobic performance. We measured flight critical oxygen partial pressure (Pcrit-), thorax temperature and thermoregulating metabolic rate to understand the extent of developmental plasticity as well as effects of developmental oxygen levels on endothermic capacity. We found that developing in hypoxia (10% oxygen) decreased thermoregulating thorax temperature when compared with moths raised in normoxia or hyperoxia (30% oxygen), when moths were warming up in atmospheres with 21-30% oxygen. In addition, moths raised in hypoxia had lower critical oxygen levels when flying. These results suggest that chronic developmental exposure to hypoxia affects the adult metabolic phenotype and potentially has implications for thermoregulatory and flight behavior.
摘要：
吸热,飞行昆虫能够达到一些最高记录的代谢率。昆虫的气管系统为飞行肌肉提供氧气，使这种高有氧需求成为可能。许多研究集中在对氧气急性变化的代谢反应上，以测试昆虫飞行代谢系统的极限，其中一些飞行昆虫在飞行代谢中表现出氧限制。这些急性研究没有说明由于氧气水平的慢性变化而由发育表型可塑性引起的可能变化。吸热蛾Manducasexta是一种模型生物，易于升高，并在飞行过程中表现出较高的胸腔温度（〜40°C）。在这项研究中，我们检查了幼虫发育氧暴露的影响，蛹,和成虫阶段对成年蛾有氧表现的影响。我们测量了飞行Pcrit-，胸部温度,和热调节代谢率，以了解发育可塑性的程度以及对吸热能力的影响。我们发现，当飞蛾在氧气含量为21-30％的大气中升温时，与在常氧或高氧（30％）中升高的飞蛾相比，在低氧（10％）中的发展降低了热调节胸腔温度。此外,在缺氧条件下生长的飞蛾在飞行时的临界氧水平较低。这些结果表明，慢性发育暴露于缺氧会影响成人的代谢表型，并可能对体温调节和飞行行为产生影响。
