Isochronous Rhythms Signal Male-Male Competition in an Asian Langur

In polygynous systems, male-male competition constitutes a core component of intra-sexual selection, where dominance contests directly favor traits that augment fighting capacity or resource control, thereby enhancing reproductive success. Vocalizations serve as a critical medium for this competition, with males employing diverse acoustic strategies including combinatorial syllable use and precise modulation of call duration, rate, and fundamental frequency. These signals allow males to advertise competitive ability while minimizing physical confrontation, thereby optimizing reproductive effort. Of particular interest are isochronous rhythms characterized by 1:1 intervals between syllable onsets, a pattern ubiquitous in human music and increasingly identified across mammalian taxa. We believed that our manuscript provides critical empirical evidence advancing the understanding of isochronous rhythms in non-human primates. By demonstrating how white-headed langurs actively modulate temporal structure in loud calls to mediate male-male competition, we establish a foundational framework for investigating isochrony in primate vocal communication. These findings offer novel insights into the adaptive role of rhythmic signaling under social-ecological constraints.<br>Here we provide the data:<br>Playback file: This contains the data required for analyzing playback experiment results<br>(1) Sound: We provide three example acoustic stimuli used in playback experiments<br>(2) Video clip: A video segment of a playback experiment showing white-headed langurs' vocal responses from stimulus reception to response, approximately 3 minutes in duration<br>(3) pbrate2: Isochrony rate of white-headed langurs' responses in playback experiments<br>(4) pdur: Duration of white-headed langurs' responses in playback experiments<br>(5) pb: Record sheet of playback experiments including parameters like experiment distance and response delay for each trial<br>(6)video: vigilance rateof of white-headed langurs' responses in playback experimentsexample：the raw dataone_seq: the data contain "rhythm ratio"<br><br><br>