Fluctuating thermal environments and time-dependent effects on fruit fly egg-hatching performance

Organismal performance in a changing environment is dependent on temporal patterns and duration of exposure to thermal variability. We experimentally assessed the time-dependent effects of thermal variability (i.e. patterns of thermal exposure) on the hatching performance of Drosophila melanogaster. Flies were collected in central Chile and maintained for four generations in laboratory conditions. Fourth generation eggs were acclimated to different thermal fluctuation cycles until hatching occurred. Our results show that the frequency of extreme thermal events has a significant effect on hatching success. Eggs exposed to 24h cycles of thermal fluctuation had a higher proportion of eggs that hatched than those acclimated to shorter (6 and 12h) and longer cycles (48h). Furthermore, eggs subjected to frequent thermal fluctuations hatched earlier than those acclimated to less frequent thermal fluctuations. Overall, we show that, egg-to-adult viability is dependent on the pattern of thermal ...变化环境下的生物体表现，取决于热波动暴露的时间模式与持续时长。本研究通过实验评估了热波动（即热暴露模式）的时间依赖性效应对黑腹果蝇（Drosophila melanogaster）孵化表现的影响。实验所用果蝇采集自智利中部，并在实验室条件下连续饲养至第4代。将第4代果蝇的卵置于不同热波动周期中进行驯化，直至其孵化。研究结果显示，极端热事件的发生频率对孵化成功率具有显著影响：相较于驯化于较短周期（6小时与12小时）及较长周期（48小时）的卵，暴露于24小时热波动周期的卵，其孵化比例更高。此外，经受频繁热波动的卵，其孵化时间早于驯化于较低频热波动的卵。总体而言，本研究证实，卵至成虫的存活率取决于热波动模式……