Data from: Anthropogenic noise reduces male reproductive investment in an acoustically signaling insect

Rapidly changing environments impose novel selection pressures on organisms, and sometimes adaptive phenotypic plasticity allows organisms to survive and reproduce in the face of environmental change. However, plastic responses can also be maladaptive. In this study, we investigate whether male reproductive investment responds plastically to varied experience with traffic noise. We exposed male crickets chronically to one of three noise treatments from the 2nd-3rdinstar until their natural death: masking traffic noise (including noise that overlaps in frequency with the male crickets' mating calls), non-masking traffic noise (an identical traffic noise track from which we digitally removed the frequencies that mask the crickets' mating call), and silence. We dissected and weighed their testes and spermatophore molds. Controlling for body mass, we found that the spermatophore molds of crickets reared in masking and non-masking noise were 29% and 24% lighter, respectively, than those of crickets reared in silence There were no differences in body mass adjusted testes mass among treatments. If spermatophore mold mass is positively associated with male reproductive output, this reduction in size could have negative fitness consequences for animals exposed to traffic noise. We encourage future work to investigate impacts of noise on reproductive investment in other study systems that are likely sensitive to anthropogenic noise (e.g., birds, frogs, singing insects).

快速变化的环境会对生物体施加新的选择压力，适应性表型可塑性（adaptive phenotypic plasticity）有时可帮助生物体在环境变化中存活并繁衍。不过，可塑性响应也可能存在适应不良的情况。本研究探讨雄性繁殖投入是否会随交通噪音暴露经历的差异而产生可塑性响应。我们将雄性蟋蟀从2-3龄期开始长期暴露于三种噪音处理组中，直至其自然死亡：掩蔽型交通噪音（包含与雄性蟋蟀求偶鸣叫频率重叠的噪音）、非掩蔽型交通噪音（将原交通噪音声轨中可掩蔽蟋蟀求偶叫声的频率通过数字手段移除后的同款噪音片段）以及静音对照组。随后我们解剖其精巢与精荚囊（spermatophore mold）并称重。在控制体重变量的前提下，我们发现暴露于掩蔽型与非掩蔽型噪音环境的蟋蟀，其精荚囊重量分别比静音对照组轻29%与24%；而各组间校正体重后的精巢重量并无显著差异。若精荚囊重量与雄性繁殖产出呈正相关，则该重量缩减可能会对暴露于交通噪音的个体造成负面的适合度后果。我们呼吁未来开展相关研究，探究人为噪音（anthropogenic noise）对其他易受其影响的研究体系（如鸟类、蛙类、鸣虫）的繁殖投入的影响。