Kikuchi Sota, Kondo Noriko, Koda Hiroki
Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Tokyo, Japan.
PLoS One. 2025 Jul 23;20(7):e0327024. doi: 10.1371/journal.pone.0327024. eCollection 2025.
In human turn-taking, speakers alternate at very short intervals while avoiding overlaps. If speakers do not receive a vocal response from another party, they often repeat their utterance after the expected response time has elapsed to elicit a reply. Intra-individual intervals tend to be longer than inter-individual intervals. Such temporal regularity in vocal exchanges has also been observed in social mammals, such as non-human primates. In contrast, vocal exchanges in birds have been studied primarily in the context of songs, with limited research on call-based vocal exchanges. Studies specifically examining intra-individual call intervals are even scarcer. In this study, we investigated vocal exchanges and their temporal patterns in Java sparrows placed face-to-face. The results revealed that they vocalized at very short intervals following the calls of the other individual. However, no significant differences were observed between the inter- and intra-individual intervals. This contrasts with the temporal characteristics of vocal exchanges observed in social mammals that have been studied to date. We propose that a possible explanation for this difference lies in the variation in social group structures between birds and mammals.
在人类对话中，说话者以非常短的间隔交替发言，同时避免话语重叠。如果说话者没有收到另一方的口头回应，他们通常会在预期的回应时间过去后重复自己的话语以引出回应。个体内部的间隔往往比个体之间的间隔更长。这种发声交流中的时间规律性在社会哺乳动物中也有观察到，比如非人类灵长类动物。相比之下，鸟类的发声交流主要是在歌曲的背景下进行研究的，对基于叫声的发声交流研究有限。专门研究个体内部叫声间隔的研究甚至更少。在这项研究中，我们调查了面对面放置的爪哇雀的发声交流及其时间模式。结果显示，它们在听到另一只鸟的叫声后会以非常短的间隔发声。然而，个体间和个体内部的间隔没有观察到显著差异。这与迄今为止研究的社会哺乳动物中观察到的发声交流的时间特征形成对比。我们提出，这种差异的一个可能解释在于鸟类和哺乳动物社会群体结构的差异。
