Field Studies on Visual and Acoustic Signaling in the "Earless" Panamanian Golden Frog, Atelopus Zeteki
Field studies were conducted on the visual and acoustic behavior of the Panamanian golden frog, Atelopus zeteki, a species lacking a tympanic middle ear. Males displayed three stereotyped behaviors in response to playbacks of male pulsed vocalizations: foot signaling, vocalization, and repositioning orientation. Frequencies of foot signaling and orientation responses were significantly increased by presentation of playback vocalizations. Vocal responses also increased (non-significantly) during the playback period and continued to increase during post-playback silence. These results provide the first experimental evidence that an "earless" anuran species displays behavioral responses to sound, and that vocalization may play an important role in communication. The forefoot waving, and possibly hindfoot raising observed in this species appear to represent visual signals used intraspecifically in male agonistic behavior. male frogs appear to rely preferentially on visual signaling (foot signaling) as compared to acoustic signaling (vocalizing). The existence and preferential use of visual signaling in this species may be correlated with their noisy, montane stream habitat. Orientation by the frogs toward the playback speaker suggests that this "earless" species of anuran is capable of localizing a sound source.
Lindquist, Erik D. and Hetherington, T. E., "Field Studies on Visual and Acoustic Signaling in the "Earless" Panamanian Golden Frog, Atelopus Zeteki" (1996). Biology Educator Scholarship. 32.