Data from: Socially flexible female choice and premating isolation in field crickets (Teleogryllus spp.)

Social influences on mate choice are predicted to influence evolutionary divergence of closely-related taxa, because of the key role mate choice plays in reproductive isolation. However, it is unclear whether females choosing between heterospecific and conspecific male signals use previously experienced social information in the same manner or to the same extent that they do when discriminating among conspecific mates only. We tested this using two field cricket sister species (Teleogryllus oceanicus and T. commodus) in which considerable information is known about the role of male calling song in premating isolation, in addition to the influence of acoustic experience on the development of reproductive traits. We manipulated the acoustic experience of replicate populations of both species and found, unexpectedly, that experience of male calling song during rearing did not change how accurate females were in choosing a conspecific over a heterospecific male song during playback trials. However, females with acoustic experience were considerably less responsive to male song compared to naïve females. Our results suggest that variation in the acoustic environment affects mate choice in both species, but that it may have a limited impact on premating isolation. The fact that social flexibility during interspecific mate discrimination does not appear to operate identically to that which occurs during conspecific mate discrimination highlights the importance of considering the context in which animals exercise socially flexible mating behaviours. We suggest an explanation for why social flexibility might be context-dependent, and discuss the consequences of such flexibility for the evolution of reproductive isolation.

配偶选择所受的社会影响被认为会影响近缘类群的进化分化，这是因为配偶选择在生殖隔离（reproductive isolation）中发挥着核心作用。然而目前仍不清楚，在异种（heterospecific）与同种（conspecific）雄性信号间进行选择的雌性个体，是否会以仅区分同种配偶时的相同方式、同等程度地利用此前获得的社会信息。本研究以两种近缘田野蟋蟀（Teleogryllus oceanicus与T. commodus）为实验对象开展验证——此前学界已对雄性求偶鸣曲在交配前隔离（premating isolation）中的作用，以及声学经历对生殖性状发育的影响有了较为充分的认知。我们对两个物种的重复种群进行了声学经历操控，却意外发现：饲养过程中接触雄性求偶鸣曲的经历，并未改变雌性在回放实验中选择同种雄性鸣曲而非异种雄性鸣曲时的准确率。但相较于未接触过声学信号的雌性个体，曾有声学经历的雌性对雄性鸣曲的响应程度显著更低。本研究结果表明，声学环境的差异会影响两个物种的配偶选择，但对交配前隔离的影响可能较为有限。异种配偶识别过程中的社会灵活性，似乎与同种配偶识别时的社会灵活性运作模式并不一致，这一现象凸显了探究动物展现社会灵活性交配行为所处情境的重要性。本研究针对社会灵活性为何会依情境而异提出了一种解释，并探讨了此类灵活性对生殖隔离进化的潜在影响。