ArticlePLoS biology2019
The evolution of the syrinx: An acoustic theory.
Article in PLoS biology, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 24 papers.
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24 citing papers in PubMed.
- Syrinx anatomy and vocalizations in New World vultures (Aves: Cathartidae): Implications for avian vocal evolution.Journal of anatomy · 2026Article
- Exploring nonlinear phenomena in animal vocalizations through oscillator theory.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2025Review
- Gharial acoustic signaling: Novel underwater pops are temporally based, context-dependent, seasonally stable, male-specific, and individually distinctive.Journal of anatomy · 2025Article
- The lungs of the finch: three-dimensional pulmonary anatomy of the zebra finch (Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2025Article
- A new neornithischian dinosaur from the Upper Jurassic Tiaojishan Formation of northern China.PeerJ · 2025Article
- Evolution of the syrinx of Apodiformes, including the vocal-learning Trochilidae (Aves: Strisores).Zoological journal of the Linnean Society · 2024Article
- Synthetic, self-oscillating vocal fold models for voice production researcha).The Journal of the Acoustical Society of America · 2024Review
- Ostrich (Struthio camelus) syrinx morphology and vocal repertoire across postnatal ontogeny and sex: Implications for understanding vocal evolution in birds.Journal of anatomy · 2024Article
- Simulation of Multiple Source Vocalization in the Larynx: How True Folds, False Folds, and Aryepiglottic Folds May Interact.Journal of speech, language, and hearing research : JSLHR · 2024Article
- Central Autonomic Mechanisms Involved in the Control of Laryngeal Activity and Vocalization.Biology · 2024Review
- Bilateral Functional Electrical Stimulation for the Treatment of Presbyphonia in a Sheep Model.The Laryngoscope · 2024Article
- An ankylosaur larynx provides insights for bird-like vocalization in non-avian dinosaurs.Communications biology · 2023Article
- Realistic three-dimensional avian vocal tract model demonstrates how shape affects sound filtering (Journal of the Royal Society, Interface · 2023Article
- Tonality over a broad frequency range is linked to vocal learning in birds.Proceedings. Biological sciences · 2022Article
- A mechanism for punctuating equilibria during mammalian vocal development.PLoS computational biology · 2022Article
- Gap junction-mediated glycinergic inhibition ensures precise temporal patterning in vocal behavior.eLife · 2021Article
- Vocalization with semi-occluded airways is favorable for optimizing sound production.PLoS computational biology · 2021Article
- 3D-FV-FE Aeroacoustic Larynx Model for Investigation of Functional Based Voice Disorders.Frontiers in physiology · 2021Article
- Categorical Rhythms Are Shared between Songbirds and Humans.Current biology : CB · 2020Article
- The vocal organ of hummingbirds shows convergence with songbirds.Scientific reports · 2020Article
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4 authors.
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No grant is acknowledged in the PubMed record.
Abstract
The unique avian vocal organ, the syrinx, is located at the caudal end of the trachea. Although a larynx is also present at the opposite end, birds phonate only with the syrinx. Why only birds evolved a novel sound source at this location remains unknown, and hypotheses about its origin are largely untested. Here, we test the hypothesis that the syrinx constitutes a biomechanical advantage for sound production over the larynx with combined theoretical and experimental approaches. We investigated whether the position of a sound source within the respiratory tract affects acoustic features of the vocal output, including fundamental frequency and efficiency of conversion from aerodynamic energy to sound. Theoretical data and measurements in three bird species suggest that sound frequency is influenced by the interaction between sound source and vocal tract. A physical model and a computational simulation also indicate that a sound source in a syringeal position produces sound with greater efficiency. Interestingly, the interactions between sound source and vocal tract differed between species, suggesting that the syringeal sound source is optimized for its position in the respiratory tract. These results provide compelling evidence that strong selective pressures for high vocal efficiency may have been a major driving force in the evolution of the syrinx. The longer trachea of birds compared to other tetrapods made them likely predisposed for the evolution of a syrinx. A long vocal tract downstream from the sound source improves efficiency by facilitating the tuning between fundamental frequency and the first vocal tract resonance.
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