Eleutherodactylus coqui

The common coqui, Eleutherodactylus coqui, produces harmonics up to approximately 12.5 kHz (Figure 2). These signals are not in the ultrasound range (>20 kHz, the human ear tends to hear sounds in the range of 20 Hz, low pitches, to 20 kHz, high pitches) but they are quite high considering that E. coqui males produce vocalizations between 1.8 kHz‒3.5 kHz to communicate with females and to defend their territory. [1]

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