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预测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）中扮演着核心角色。然而目前仍不清楚：当雌性在异种（heterospecific）与同种（conspecific）雄性信号间进行选择时，其利用此前获得的社会信息的方式与程度，是否与其仅在同种配偶间进行辨别时一致。我们以两种田野蟋蟀姐妹种（Teleogryllus oceanicus 与 T. commodus）为实验对象开展了相关检验，针对雄性鸣唱声在交配前生殖隔离中的作用，以及声学经验对繁殖性状发育的影响，学界已有大量研究积累。我们对两个物种的重复种群进行了声学经验操控，结果意外发现：若虫期接触雄性鸣唱声的经历，并未改变雌性在回放实验中选择同种雄性鸣唱声而非异种鸣唱声时的判别准确性。不过，相较于未经历过声学刺激的雌性（naïve females），具有声学经验的雌性对雄性鸣唱声的响应程度显著更低。我们的研究结果表明，声学环境的差异会影响两个物种的配偶选择行为，但对交配前生殖隔离的影响或较为有限。种间配偶辨别时的社会灵活性，似乎与同种配偶辨别时的社会灵活性并不相同，这一发现凸显了考量动物行使社会灵活性交配行为所处情境的重要性。我们针对社会灵活性为何可能具有情境依赖性提出了一种解释，并探讨了此类灵活性对生殖隔离进化的潜在影响。