The anuran vocal sac: a tool for multimodal signalling

Area of Science:

• Animal Behavior
• Bioacoustics
• Chemical Ecology

Background:

• Anurans primarily use vocalizations for communication, but other sensory modalities are also employed.
• The anuran vocal sac's role in non-acoustic signaling has been historically overlooked, often viewed as secondary to sound production.
• Diverse vocal sac morphology suggests potential roles beyond acoustics.

Purpose of the Study:

• To explore the multimodal communication roles of the anuran vocal sac, including visual and chemical signaling.
• To investigate the significance of non-acoustic cues from the vocal sac in anuran species recognition and mate choice.
• To highlight anurans as suitable models for studying multimodal communication systems.

Main Methods:

• Review of existing literature on anuran communication and vocal sac functions.
• Analysis of vocal sac diversity in coloration and shape across anuran species.
• Consideration of experimental approaches for studying multimodal signaling in frogs.

Main Results:

• Evidence suggests vocal sac visual properties play a significant role in signaling.
• Airborne chemical signaling, though less studied, is increasingly recognized in terrestrial anurans.
• Some anuran species, particularly secondarily mute ones, rely heavily on vocal sac-derived chemical cues.

Conclusions:

• The anuran vocal sac is a versatile signaling organ involved in acoustic, visual, and chemical communication.
• Integrating multiple sensory cues is crucial for species recognition and mate choice in anurans.
• Anurans offer a valuable model system for advancing the study of multimodal communication.