Data from: Male serrate-legged treefrogs adjust competition strategies according to visual or chemical cues from females

There is increasing evidence that many anurans use multimodal cues to detect, discriminate and/or locate conspecifics and thus modify their behaviors. To date, however, most studies have focused on the roles of multimodal cues in female choice or male–male interactions. In the present study, we conducted an experiment to investigate whether male serrate-legged small treefrogs (Kurixalus odontotarsus) used visual or chemical cues to detect females and thus altered their competition strategies in different calling contexts. Three acoustic stimuli (advertisement calls, aggressive calls and compound calls) were broadcast in a randomized order after a spontaneous period to focal males in one of four treatment groups: combined visual and chemical cues of a female, only chemical cues, only visual cues and a control (with no females). We recorded the vocal responses of the focal males during each 3 min period. Our results demonstrate that males reduce the total number of calls in response to the presence of females, regardless of how they perceived the females. In response to advertisement calls and compound calls, males that perceived females through chemical cues produced relatively fewer advertisement calls but more aggressive calls. In addition, they produced relatively more aggressive calls during the playback of aggressive calls. Taken together, our study suggests that male K. odontotarsus adjust their competition strategies according to the visual or chemical cues of potential mates and highlights the important role of multisensory cues in male frogs' perception of females.

越来越多的证据表明，诸多无尾两栖类（anurans）会借助多模态信号（multimodal cues）来探测、识别乃至定位同种个体（conspecifics），并以此调整自身行为。然而迄今为止，绝大多数相关研究均聚焦于多模态信号在雌性配偶选择或是雄性间竞争互动（male–male interactions）中的作用。
在本研究中，我们开展了一项实验，以探究雄性锯齿腿小树蛙（Kurixalus odontotarsus）是否会借助视觉或化学信号探测雌性个体，并据此在不同鸣叫情境下调整其竞争策略。我们将三种声学刺激信号（acoustic stimuli）——求偶鸣叫（advertisement calls）、攻击性鸣叫（aggressive calls）与复合鸣叫（compound calls）——在目标雄性个体进入自发鸣叫期（spontaneous period）后，以随机顺序播放给隶属于四种处理组（treatment groups）之一的目标雄性个体；四种处理组分别为：雌性个体视觉与化学信号联合组、仅化学信号组、仅视觉信号组，以及无雌性相关信号的对照组。我们记录了每段3分钟测试时段内目标雄性个体的鸣叫反应。
研究结果显示，无论雄性个体通过何种途径感知到雌性的存在，其总鸣叫次数均会出现下降。当播放求偶鸣叫与复合鸣叫时，借助化学信号感知到雌性的雄性个体所发出的求偶鸣叫次数相对更少，但攻击性鸣叫次数相对更多。此外，在攻击性鸣叫回放播放期间，这类个体所发出的攻击性鸣叫次数同样相对更多。
综上，本研究表明雄性锯齿腿小树蛙会依据潜在配偶的视觉或化学信号调整其竞争策略，并凸显了多感官信号在雄性蛙类感知雌性个体过程中的重要作用。