Naguib M, Todt D
Institut für Verhaltensbiologie, Freie Universität Berlin
Anim Behav. 1997 Dec;54(6):1535-1543. doi: 10.1006/anbe.1997.9997.
During vocal interactions birds can time their song output so that their songs overlap those of a conspecific. Such overlapping is usually interpreted as a directed signal of arousal or as a signal of readiness to escalate contests. Inevitably, these interactions can often be heard by other conspecifics. To investigate if these conspecifics would perceive and use information derived from listening to others' interactions we conducted playback experiments in the field on male territorial nightingales, Luscinia megarhynchos. We tested whether asymmetric interactions, in which one bird overlaps the song of another individual, influences the behaviour of additional, passive conspecific receivers. To test the influence of song overlapping on a third individual, each subject received one playback treatment in which two intruders were simulated by a dual speaker playback design. Songs broadcast from one loudspeaker overlapped those from the other loudspeaker. Subjects responded more intensely at the side of the overlapper than at the side of the loudspeaker from which the song that was overlapped was broadcast. These differences in response persisted in a second test in which songs of only one of the formerly interacting rivals were played. The results suggest that, even if song overlapping is a signal directed towards the singer whose song is overlapped, this information is perceived and used by additional receivers. Such information on rivals' behaviour during an interaction might help an individual decide which strategies to adopt in possible future interactions with these conspecifics.Copyright 1997 The Association for the Study of Animal Behaviour
在发声互动过程中，鸟类能够调整它们歌声的输出时间，以使自己的歌声与同种个体的歌声重叠。这种重叠通常被解释为一种有针对性的唤起信号，或者是准备升级竞争的信号。不可避免的是，这些互动往往会被其他同种个体听到。为了研究这些同种个体是否会感知并利用从倾听其他个体互动中获得的信息，我们在野外对雄性领地夜莺（歌鸲）进行了回放实验。我们测试了不对称互动（即一只鸟的歌声与另一只个体的歌声重叠）是否会影响其他被动的同种接收者的行为。为了测试歌声重叠对第三个个体的影响，每个受试者都接受了一种回放处理，即通过双扬声器回放设计模拟两个入侵者。从一个扬声器播放的歌声与从另一个扬声器播放的歌声重叠。与播放被重叠歌声的扬声器一侧相比，受试者在重叠者一侧的反应更强烈。在第二次测试中，只播放之前互动的对手之一的歌声，这些反应差异仍然存在。结果表明，即使歌声重叠是针对歌声被重叠的歌手的信号，但这些信息仍会被其他接收者感知并利用。关于对手在互动过程中行为的此类信息可能会帮助个体决定在未来与这些同种个体的可能互动中采取哪些策略。版权所有1997年动物行为研究协会
