ArticleProceedings. Biological sciences2023
Vocal tract shape variation contributes to individual vocal identity in African penguins.
Article in Proceedings. Biological sciences, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.
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3 citing papers in PubMed, 5 citations in OpenAlex.
- Sound Guides Object Size Choices in African Penguins Through Pitch-Size Association.Annals of the New York Academy of Sciences · 2026Article
- Nonlinear vocal phenomena in African penguin begging calls: occurrence, significance and potential applications.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2025Article
- Vocal tract shape variation contributes to individual vocal identity in African penguins.Proceedings. Biological sciences · 2023Article
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Authors and funding
12 authors at 3 institutions in 4 countries.
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No grant is acknowledged in the PubMed record.
Abstract
Variation in formant frequencies has been shown to affect social interactions and sexual competition in a range of avian species. Yet, the anatomical bases of this variation are poorly understood. Here, we investigated the morphological correlates of formants production in the vocal apparatus of African penguins. We modelled the geometry of the supra-syringeal vocal tract of 20 specimens to generate a population of virtual vocal tracts with varying dimensions. We then estimated the acoustic response of these virtual vocal tracts and extracted the centre frequency of the first four predicted formants. We demonstrate that: (i) variation in length and cross-sectional area of vocal tracts strongly affects the formant pattern, (ii) the tracheal region determines most of this variation, and (iii) the skeletal size of penguins does not correlate with the trachea length and consequently has relatively little effect on formants. We conclude that in African penguins, while the variation in vocal tract geometry generates variation in resonant frequencies supporting the discrimination of conspecifics, such variation does not provide information on the emitter's body size. Overall, our findings advance our understanding of the role of formant frequencies in bird vocal communication.
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