Twin vocal folds as a novel evolutionary adaptation for vocal communications in lemurs.
Sci Rep
; 14(1): 3631, 2024 02 13.
Article
en En
| MEDLINE
| ID: mdl-38351102
ABSTRACT
Primates have varied vocal repertoires to communicate with conspecifics and sometimes other species. The larynx has a central role in vocal source generation, where a pair of vocal folds vibrates to modify the air flow. Here, we show that Madagascan lemurs have a unique additional pair of folds in the vestibular region, parallel to the vocal folds. The additional fold has a rigid body of a vocal muscle branch and it is covered by a stratified squamous epithelium, equal to those of the vocal fold. Such anatomical features support the hypothesis that it also vibrates in a manner like the vibrations that occur in the vocal folds. To examine the acoustic function of the two pairs of folds, we made a silicone compound model to demonstrate that they can simultaneously vibrate to lower the fundamental frequency and increase vocal efficiency. Similar acoustic effects are achieved using different features of the larynx for the other primates, e.g., by vibrating multiple sets of ventricular folds in several species and further by an evolutionary modification of enlarged larynx in howler monkeys. Our multidisciplinary approaches found that these functions were acquired through a unique evolutionary adaptation of the twin vocal folds in Madagascan lemurs.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Pliegues Vocales
/
Lemur
Límite:
Animals
Idioma:
En
Año:
2024
Tipo del documento:
Article