Effects of flight and food stress on energetics, reproduction, and lifespan in the butterfly Melitaea cinxia

Environmental change can have drastic effects on natural populations. To successfully predict such effects, we need to understand how species that follow different life-history strategies respond to stressful conditions. Here I focus on two stressors, increased flight and dietary restriction, and their effects on bioenergetics and life-history. Using the Glanville fritillary butterfly (Melitaea cinxia), I subjected mated females to three treatments: (1) control conditions, (2) repeated forced flight with unlimited food, and (3) repeated forced flight coupled with food restriction. Interestingly, flight increased fecundity: females in both flight treatments initiated oviposition earlier, laid more egg clutches, and had higher total fecundity than control females. However, food-restriction by 50% reduced clutch size and resulted in an approximately 25% decrease in total fecundity compared to flown females with unlimited food. There were no differences in egg wet mass, water content or ha...环境变化可对自然种群产生剧烈影响。为精准预测此类生态效应，我们需要明晰采取不同生活史策略（life-history strategies）的物种如何应对胁迫环境。本研究聚焦两种胁迫因子：飞行负荷增加与饮食限制，及其对生物能学（bioenergetics）与生活史的影响。实验以格纹蛱蝶（Melitaea cinxia）为研究对象，将已交配的雌蝶分为三组进行处理：(1) 对照组环境；(2) 持续强制飞行且食物充足组；(3) 持续强制飞行伴饮食限制组。值得注意的是，飞行可提升雌蝶繁殖力（fecundity）：两组飞行处理的雌蝶均较对照组雌蝶更早启动产卵（oviposition）、产下更多卵块，且总繁殖力显著高于对照组。然而，与食物充足的飞行组雌蝶相比，施加50%饮食限制会降低单卵块的卵粒数量，并使总繁殖力下降约25%。各组雌蝶所产卵的湿重、含水量及[原文未完整表述的指标]均无显著差异。