Functional morphology of the Alligator mississippiensis larynx with implications for vocal production
Abstract
Sauropsid vocalization is mediated by the syrinx in birds and the larynx in extant reptiles; but whereas avian vocal production has received much attention, the vocal mechanism of basal reptilians is poorly understood. The American alligator (Alligator mississippiensis) displays a large vocal repertoire during mating and in parent-offspring interactions. Although vocal outputs of these behaviors have received some attention, the underlying mechanism of sound production remains speculative. Here, we investigate the laryngeal anatomy of juvenile and adult animals by macroscopic and histological methods. Observations of the cartilaginous framework and associated muscles largely corroborate earlier findings, but one muscle, the cricoarytenoideus, exhibits a heretofore unknown extrinsic insertion that has important implications for effective regulation of vocal fold length and tension. Histological investigation of the larynx revealed a layered vocal fold morphology. The thick lamina propria consists of non-homogenous extracellular matrix containing collagen fibers that are tightly packed below the epithelium but loosely organized deep inside the vocal fold. We found few elastic fibers but comparatively high proportions of hyaluronan. Similar organizational complexity is also seen in mammalian vocal folds and the labia of the avian syrinx: convergent morphologies that suggest analogous mechanisms for sound production. In tensile tests, alligator vocal folds demonstrated a linear s…
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Percussion is a means of acoustic signalling involving sounds created by body-body or body‐object striking, such as jaw pops and headslaps.
“A third means of acoustic signalling is percussion, involving sounds created by body–body or body‐object striking, such as jaw pops and headslaps (Vergne et al. 2009; Riede et al. 2011, 2015).”
From Roars, Rumbles, and Resonance: A Systematic Review and Meta‐Analysis of Crocodylian Acoustic Signals (2026) · cites this paper as Riede et al. 2015
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- Authors
- Riede, T., Li, Z., Tokuda, I. T., & Farmer, C. G.
- Affiliations
- Midwestern University (US)
- The University of Texas at Austin (US)
- Ritsumeikan University (JP)
- University of Utah (US)
- Corresponding author
- Riede, Tobias
- Venue
- Journal of Experimental Biology
- Publisher
- The Company of Biologists
- Published
- 2015-04-01
- Volume
- 218
- Issue
- 7
- Pages
- 991-998
- ISSN
- 0022-0949 (ISSN-L)
- 1477-9145
- OpenAlex
- W2162165024
- Cited by
- 38
- References
- 46
- Citations by year
- 2026: 1 · 2025: 3 · 2024: 1 · 2023: 6 · 2022: 2 · 2021: 1 · 2020: 6 · 2019: 5 · 2018: 4 · 2017: 2 · 2016: 3 · 2015: 4
- FWCI
- 3.78
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Journal of Experimental Biology (publishedVersion)
- PubMed (publishedVersion)
- Funders
- Japan Society for the Promotion of Science (23300071)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Developmental Biology › Animal Vocal Communication and Behavior
- Health Sciences › Medicine › Urology › Comparative Animal Anatomy Studies
- Health Sciences › Medicine › Physiology › Voice and Speech Disorders
- Keywords
- Alligator mississippiensis, larynx, vocal fold histology, lamina propria, hyaluronic acid, extracellular matrix, vocal fold tension, stress-strain behavior, acoustic space, mating calls
- MeSH terms
- Alligators and Crocodiles, Animals, Biomechanical Phenomena, Computer Simulation, Female, Larynx, Male, Mucous Membrane, Vocal Cords, Vocalization, Animal
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