Facultative polyandry protects females from compromised male fertility caused by heatwave conditions

Females are able to recover fertility through polyandry when male fertility is compromised by heatwaves. Facultative polyandry enables females to recover from losses to fitness which can have consequences both at the individual level as well as at the population level. Across the animal kingdom females of many species mate multiply and the costs of mating multiply can be mitigated by polyandry. Under global climate change heatwaves are getting more intense and persistent with male-specific sterily becoming commonplace in many species (especially ectotherms). Here we show how polyandry could be a key proximate mechanism in improving female fitness between mating episodes.当雄性生育能力因热浪受损时，雌性可通过一妻多夫制（polyandry）恢复生育能力。兼性一妻多夫制（facultative polyandry）可帮助雌性弥补适合度损失，这类损失会对个体层面与种群层面均产生影响。在整个动物界中，诸多物种的雌性均会进行多次交配，而一妻多夫制可缓解多次交配所带来的代价。在全球气候变化背景下，热浪的强度与持续时长均有所增加，雄性特异性不育在诸多物种（尤其是变温动物）中愈发常见。本研究阐明了一妻多夫制为何可作为改善雌性各次交配间隔期内适合度的核心近因机制。