Data from: Modality interactions alter the shape of acoustic mate preference functions in gray treefrogs

Sexual selection takes place in complex environments where females evaluating male mating signals are confronted with stimuli from multiple sources and modalities. The pattern of expression of female preferences may be influenced by interactions between modalities, changing the shape of female preference functions, and thus ultimately altering the selective landscape acting on male signal evolution. We tested the hypothesis that the responses of female gray treefrogs, Hyla versicolor, to acoustic male advertisement calls are affected by interactions with visual stimuli. We measured preference functions for several call traits under two experimental conditions: unimodal (only acoustic signals presented), and multimodal (acoustic signals presented along with a video-animated calling male). We found that females were more responsive to multimodal stimulus presentations and, compared to unimodal playbacks, had weaker preferences for temporal call characteristics. We compared the preference functions obtained in these two treatments to the distribution of male call characteristics to make inferences on the strength and direction of selection expected to act on male calls. Modality interactions have the potential to influence the course of signal evolution and thus are an important consideration in sexual selection studies.性选择发生于复杂环境中，此时评估雄性择偶信号的雌性个体将面临来自多重来源与多种模态的刺激。雌性择偶偏好的表达模式可能受不同模态间交互作用的影响，进而改变雌性偏好函数的形态，最终改变作用于雄性信号演化的选择景观。本研究检验了如下假说：灰树蛙（Hyla versicolor）的雌性对雄性广告鸣叫声学信号的响应，会受到视觉刺激交互作用的调控。我们在两种实验条件下测定了多种鸣叫性状的偏好函数：单模态（unimodal）条件（仅呈现声学信号）与多模态（multimodal）条件（同步呈现声学信号与视频动画模拟的鸣叫雄性个体）。实验结果显示，相较于单模态回放处理，雌性对多模态刺激的响应更为强烈，且对鸣叫时间特征的偏好更弱。我们将两种处理下得到的偏好函数与雄性鸣叫性状的分布进行比对，以此推断作用于雄性鸣叫的选择强度与方向。模态交互有望影响信号演化的进程，因此在性选择研究中是一项重要的考量因素。