Duengen Diandra, Jadoul Yannick, Ravignani Andrea
Comparative Bioacoustics Research Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.
Zoo Cleves ("Tiergarten Kleve"), Kleve, Germany.
BMC Ecol Evol. 2025 Sep 2;25(1):90. doi: 10.1186/s12862-025-02404-9.
The duration of animal vocalizations varies between and within species. Which mammals can learn to control this duration? Such respiratory production learning is a scarcely studied subcomponent of vocal learning. Here, we test the hypothesis that harbor seals () are capable of respiratory production learning by testing whether a harbor seal can be trained to i) actively control its vocalization’s duration in two directions (short and long), and ii) exceed the pre-experimental vocalization’s duration (min = 0.202 s, max = 2.621 s). The seal learned to produce uninterrupted vocalizations spanning more than two orders of magnitude in duration, from 79 ms to 9.23 s. Our findings demonstrate a remarkable level of respiratory control in a harbor seal: this respiratory production learning encompasses an extensive range of sound durations and arises at a young age. Producing durations that span such a magnitude is hardly reported in the non-human animal literature; this capacity may be orthogonal to other vocal learning modules and should be tested in more species, both vocal production learners and non-learners.
The online version contains supplementary material available at 10.1186/s12862-025-02404-9.
动物发声的持续时间在不同物种之间以及同一物种内部都有所不同。哪些哺乳动物能够学会控制这种持续时间呢？这种呼吸产生学习是发声学习中一个鲜有研究的子成分。在这里，我们通过测试港海豹是否能够被训练来验证港海豹能够进行呼吸产生学习的假设：i）在两个方向（短和长）上主动控制其发声的持续时间，以及ii）超过实验前发声的持续时间（最小值 = 0.202秒，最大值 = 2.621秒）。这只海豹学会了发出持续时间跨越两个数量级以上的不间断发声，从79毫秒到9.23秒。我们的研究结果表明港海豹具有显著水平的呼吸控制能力：这种呼吸产生学习涵盖了广泛的声音持续时间范围，并且在幼年时就出现了。产生跨越如此幅度的持续时间在非人类动物文献中鲜有报道；这种能力可能与其他发声学习模块无关，应该在更多物种中进行测试，包括发声产生学习者和非学习者。
在线版本包含可在10.1186/s12862 - 025 - 02404 - 9获取的补充材料。
