Data from: Sexual signal loss: the link between behavior and rapid evolutionary dynamics in a field cricket

1. Sexual signals may be acquired or lost over evolutionary time, and are tempered in their exaggeration by natural selection. 2. In the Pacific field cricket, Teleogryllus oceanicus, a mutation (“flatwing”) causing loss of the sexual signal, the song, spread in < 20 generations in two of three Hawaiian islands where the crickets have been introduced. Flatwing (as well as some normal-wing) males behave as satellites, moving towards and settling near calling males to intercept phonotactic females. 3. From 2005-2012, we surveyed crickets and their responses to conspecific song, noting the morph and number of males and females before and after experimental playbacks. The three Hawaiian islands consistently contained different proportions of flatwing crickets, ranging from about 90% of males on Kauai to 50% on Oahu to rare on the Big Island of Hawaii. 4. Flatwing and normal-wing males do not appear to differ in responsiveness to playback, a behavior that should influence the likelihood of a male encountering a phonotactic female. Instead, male and female crickets from populations in which little to no calling song is perceptible during development tended to seek out callers more readily than crickets that developed in noisier environments. Such increased phonotaxis makes females more likely to find either the caller to which they are responding or to encounter a flatwing (or normal male satellite) that has also been attracted to the song. 5. Our evidence suggests that pre-existing behavioral plasticity (manifest as flexible responses to social – particularly acoustic – information in the environment) is associated with the rapid spread of the flatwing trait. Different social environments select for differential success of flatwing or normal-wing males, which in turn alters the social environment itself.

1. 性信号可在进化历程中获得或丢失，其表达的夸张程度会受到自然选择的约束。2. 在太平洋田野蟋蟀（Teleogryllus oceanicus）中，一种导致其性信号——鸣曲——丢失的“平翅（flatwing）”突变，在该物种被引入的三个夏威夷群岛中的两个，仅用不足20代便快速扩散。平翅型（以及部分正常翅型）雄性会以卫星雄性的身份活动：移动并定居于鸣曲雄性附近，以拦截趋声雌性。3. 2005年至2012年间，我们对蟋蟀及其对同种鸣曲的反应开展了调查，记录了实验回放前后的雄性与雌性的翅型及个体数量。三个夏威夷群岛的平翅蟋蟀比例始终存在稳定差异：考艾岛的雄性平翅比例约为90%，瓦胡岛为50%，而夏威夷大岛的平翅雄性则极为罕见。4. 平翅型与正常翅型雄性对鸣曲回放的响应并无显著差异，这一行为本应影响雄性邂逅趋声雌性的概率。与之相反，在发育过程中几乎无法感知鸣曲的种群中的雌雄个体，相比成长于嘈杂环境中的个体，更易主动定位并寻找鸣曲者。这种增强的趋声行为会使雌性更有可能找到其所响应的鸣曲雄性，或是邂逅同样被鸣曲吸引的平翅型（或正常翅型）卫星雄性。5. 我们的研究证据表明，先天存在的行为可塑性——表现为对环境中社会信息（尤其是声学信息）的灵活响应——与平翅性状的快速扩散密切相关。不同的社会环境会对平翅型或正常翅型雄性的生存优势产生差异化选择，而这反过来又会改变种群自身的社会环境。