Data from: Social plasticity in choosiness in green tree frogs, Hyla cinerea

Mate choice is an important driver of the evolution of sexual traits and can promote divergence and speciation. Understanding the underlying variation in mate choice decisions is crucial to understand variation in the strength and direction of sexual selection. We explored whether variation in the social environment influences mate choice decisions and focus on the aspect of mate choice termed choosiness (i.e. the effort invested in mate assessment and acquisition). Using call playbacks, we manipulated the social environment female green tree frogs would experience as they entered a chorus, and then we conducted two-choice playback trials to assess whether females exhibited social plasticity in choosiness. We explored social plasticity at 2 levels: in one experiment, we manipulated the presence or absence of preferred (attractive) and less preferred (unattractive) conspecific males (i.e. intraspecific context), and in the other experiment, we manipulated the presence or absence of preferred (conspecific) and less preferred closely related heterospecific males (i.e. interspecific context). We found that in the intraspecific context, the presence of attractive males increased choosiness, while absence of attractive males reduced choosiness. In the interspecific context, choosiness remained stable in most treatments, but was lowered when females experienced a mixture of conspecific and heterospecific calls. We discuss the effect of social plasticity in choosiness on mate choice decisions and highlight its evolutionary consequences.

配偶选择是性征演化的重要驱动力，可推动种群分化与物种形成。明晰配偶选择决策背后的变异规律，对于理解性选择的强度与方向变异至关重要。本研究探究社会环境变异是否会影响配偶选择决策，并聚焦于被称为择偶挑剔度（choosiness）的配偶选择维度——即个体在配偶评估与获取过程中投入的精力。我们通过鸣声回放（call playbacks）实验，调控绿树蛙雌性进入鸣声集群时所处的社会环境，随后开展二选一鸣声回放试验（two-choice playback trials），以评估雌性在择偶挑剔度上是否存在社会可塑性。我们从两个层面探究社会可塑性：在一项实验中，我们调控具有吸引力（偏好性）与缺乏吸引力（低偏好性）的同种雄性个体的存在与否（即种内情境）；在另一项实验中，我们调控具有吸引力（同种）与低偏好性的近缘异种雄性个体的存在与否（即种间情境）。研究结果显示，在种内情境中，吸引力雄性的存在会提升雌性的择偶挑剔度，而吸引力雄性的缺失则会降低其择偶挑剔度；在种间情境中，多数处理组下雌性的择偶挑剔度保持稳定，但当雌性接触到同种与异种鸣声的混合信号时，其择偶挑剔度会出现下降。我们讨论了择偶挑剔度的社会可塑性对配偶选择决策的影响，并强调了其演化后果。