Hearing and Sound Production in the Aquatic Salamander, Amphiuma means

Abstract

Abstract: In contrast to anurans, acoustic communication and hearing within Order Urodela is poorly understood. Several studies have documented sound production in a few salamander species; however, these studies did not examine auditory ranges of these salamanders simultaneously. Two-Toed Amphiumas (Amphiuma means) were used as a model to examine the ecological significance of sound production in salamanders. We conducted a series of behavioral trials to validate sound production in this species, and auditory-evoked potentials (AEPs) were measured to assess hearing abilities. Amphiuma means produced three unique broadband acoustic signals: low-, mid-, and high-frequency clicks. All acoustic signals were produced when A. means were placed in groups, but not when housed individually. The audiogram was relatively flat at 100–700 Hz; above this range, sensitivity declined with increasing frequency. No auditory responses were detected between 1.5 and 10 kHz. The dominant frequencies of the acoustic signals (...