Watson, Stuart KyleZali, MaraFalk, NikolaWidmer, PaulManser, Marta B.2025-06-122025-06-122024-12Watson, S.K., Zali, M., Falk, N., Widmer, P. & Manser, M.B. 2024 Inter-call intervals, but not call durations, adhere to Menzerath’s Law in the submissive vocal bouts of meerkats. Royal Society Open Science 11: 241351. https://doi.org/10.1098/rsos.241351.2054-570310.1098/rsos.241351http://hdl.handle.net/2263/102794Diverse information encoding systems, including human language, the vocal and gestural systems of non-human animals and the structure of DNA and proteins, have been found to conform to ‘Menzerath’s Law’—a negative relationship between the number of units composing a sequence, and the size of those units. Here, we test for the presence of Menzerath’s Law in the vocal bouts produced in a submissive context by meerkats (Suricata suricatta). Using a suite of Bayesian mixed effects models, we examined 1676 vocal bouts produced by 89 wild meerkats, ranging from 1 to 590 calls in length, to determine whether the number of calls composing each bout had a negative relationship with the duration of those calls or their inter-call intervals. In contradiction to Menzerath’s Law, we found that the duration of vocalizations had a positive relationship with the number of calls in a bout. However, the duration of intervals between calls did have a negative relationship with bout size. Moreover, both calls and intervals had longer durations the closer they were positioned to the end of the bout. These findings highlight the multi-faceted ways in which efficiency trade-offs can occur in the vocal repertoires of non-human animals, shaping variability in the production of signal forms.en© 2024 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License.Animal communicationVocal behaviourMenzerath’s lawQuantitative linguisticsArticle