Data from: Assessment of rival males through the use of multiple sensory cues in the fruitfly Drosophila pseudoobscura

Environments vary stochastically, and animals need to behave in ways that best fit the conditions in which they find themselves. The social environment is particularly variable, and responding appropriately to it can be vital for an animal’s success. However, cues of social environment are not always reliable, and animals may need to balance accuracy against the risk of failing to respond if local conditions or interfering signals prevent them detecting a cue. Recent work has shown that many male Drosophila fruit flies respond to the presence of rival males, and that these responses increase their success in acquiring mates and fathering offspring. In Drosophila melanogaster males detect rivals using auditory, tactile and olfactory cues. However, males fail to respond to rivals if any two of these senses are not functioning: a single cue is not enough to produce a response. Here we examined cue use in the detection of rival males in a distantly related Drosophila species, D. pseudoobscura, where auditory, olfactory, tactile and visual cues were manipulated to assess the importance of each sensory cue singly and in combination. In contrast to D. melanogaster, male D. pseudoobscura require intact olfactory and tactile cues to respond to rivals. Visual cues were not important for detecting rival D. pseudoobscura, while results on auditory cues appeared puzzling. This difference in cue use in two species in the same genus suggests that cue use is evolutionarily labile, and may evolve in response to ecological or life history differences between species.

环境存在随机波动，动物需要采取最适配所处环境条件的行为策略。社会环境尤其复杂多变，对其做出恰当响应对动物的生存繁衍至关重要。然而，社会环境的相关线索并非始终可靠，当局部环境出现变化或存在干扰信号导致动物无法侦测到线索时，动物需要在判断准确性与未及时做出响应的风险之间进行权衡。

近期研究表明，诸多雄性果蝇（Drosophila）会对同类雄性竞争者的存在做出响应，此类响应可提升其获取配偶与繁衍后代的成功率。在黑腹果蝇（Drosophila melanogaster）中，雄性个体通过听觉、触觉与嗅觉线索侦测竞争者。但若上述任意两种感官功能受损，雄性便无法对竞争者做出响应——仅单一线索不足以触发响应行为。

本研究针对亲缘关系较远的拟暗果蝇（D. pseudoobscura）展开，探究其侦测雄性竞争者时所依赖的线索类型。研究中我们通过操控听觉、嗅觉、触觉与视觉线索，分别评估单一感官线索及多感官组合线索的重要性。

与黑腹果蝇不同，拟暗果蝇雄性个体需要完整的嗅觉与触觉线索才能对竞争者做出响应。视觉线索对拟暗果蝇的竞争者侦测并无作用，而听觉线索的实验结果则较为费解。同一果蝇属内两个物种在感官线索使用模式上的差异表明，感官线索的依赖策略具有进化可塑性，可能会随物种间生态或生活史特征的差异而发生演化。