Frogs and toads produce a rich variety of sounds, calls, and songs during their courtship and mating rituals.
The callers, usually males, make stereotyped sounds in order to advertise their location, their mating readiness and their willingness to defend their territory; listeners respond to the calls by return calling, by approach, and by going silent.
These responses have been shown to be important for species recognition, mate assessment, and localization.
Beginning with the pioneering experiments of Robert Capranica in the 1930s[1] using playback techniques with normal and synthetic calls, behavioral biologists and neurobiologists have teamed up to use frogs and toads as a model system for understanding the auditory function and evolution.
Acoustic communication is essential for the frog's survival in both territorial defense and in localization and attraction of mates.
Frogs and toads largely ignore sounds that are not conspecific calls or those of predators,[2] with only louder noises startling the animals.
Species that have a narrow mating season due to ponds that dry up have the most vigorous calls.
Narins has found female frog species that use solid surfaces, such as blades of grass and logs, upon which they tap rhythmically to attract mates.
In order for vocalizations to be produced, the respiratory airflow goes from the lungs, passing through the larynx, and into the oral cavity.
Frogs produce sound from the air sac below their mouth that from the outside, is seen to inflate and deflate.
[10] For the Concave-eared torrent frog (Amolops tormotus), they produce sounds in the ultrasonic range.
The medulla-spinal cord junction contains the hypoglossal and vagus nuclei, which are vital to organize the calling and breathing motor patterns.
A recent project on hearing aids is based on how female frogs find their mates.
An additional challenge is that she is localizing his call while listening to the many other frogs in the chorus, and to the noise of the stream and insects.
The breeding pond is a very noisy place, and females must distinguish a male's calls from the other noise.
The timing and frequency of the sound also play a part in frog communication and may be used in Feng's work.