Data from: Wind- and rain-induced vibrations impose different selection pressures on multimodal signaling

The world is a noisy place, and animals have evolved a myriad of strategies to communicate in it. Animal communication signals are, however, often multimodal; their components can be processed by multiple sensory systems, and noise can thus affect signal components across different modalities. We studied the effect of environmental noise on multimodal communication in the túngara frog (Physalaemus pustulosus). Males communicate with rivals using airborne sounds combined with call-induced water ripples. We tested males under control as well as noisy conditions in which we mimicked rain- and wind-induced vibrations on the water surface. Males responded more strongly to a multimodal playback in which sound and ripples were combined, compared to a unimodal sound-only playback, but only in the absence of rain and wind. Under windy conditions, males decreased their response to the multimodal playback, suggesting that wind noise interferes with the detection of rival ripples. Under rainy conditions, males increased their response, irrespective of signal playback, suggesting that different noise sources can have different impacts on communication. Our findings show that noise in an additional sensory channel can affect multimodal signal perception and thereby drive signal evolution, but not always in the expected direction.自然环境本就充斥着噪声，动物已演化出无数种策略以在这样的环境中完成信息交流。然而，动物的通讯信号通常为多模态信号：其组成成分可通过多种感官系统进行处理，因此噪声可对不同模态下的信号成分产生影响。本研究以泡蟾（Physalaemus pustulosus）为研究对象，探究了环境噪声对其多模态通讯的影响。雄性泡蟾会通过结合空气传播鸣声与鸣声诱发的水面波纹，与同类竞争者进行通讯。我们分别在对照条件与模拟降雨、风力诱发的水面振动噪声条件下，对雄性泡蟾进行了测试。相较于仅播放单模态鸣声的信号回放，雄性泡蟾对结合了鸣声与水面波纹的多模态信号回放的响应更为强烈，但这一现象仅在无降雨与风力的对照条件下出现。在风力噪声条件下，雄性泡蟾对多模态信号回放的响应有所降低，这表明风力噪声会干扰其对竞争者所产生的水面波纹的识别。而在降雨噪声条件下，无论播放何种信号刺激，雄性泡蟾的响应均有所提升，这说明不同来源的噪声对动物通讯的影响存在差异。本研究结果表明，额外感官通道中的噪声可影响多模态信号的感知过程，进而推动信号演化，但这一影响并不总是符合预期方向。