Do Male White-Lipped Frogs Use Seismic Signals for Intraspecific Communication?

Abstract

Abstract Modern frogs and toads possess a structurally unique saccule, endowing them with seismic sensitivity greater than that observed so far in any other group of terrestrial vertebrates. In synchrony with their advertisement calls, approximately half of the calling males of one frog species, the Puerto-Rican white-lipped frog (Leptodactylus albilabris), produce impulsive seismic signals (thumps). The spectral distribution of power in these seismic signals matches precisely the spectral sensitivity of the frog's saccule. The signals have sufficient amplitude to be sensed easily by the frog's saccule up to several meters from the source—well beyond the typical spacing when these frogs are calling in a group. This circumstantial evidence suggests that white-lipped frogs may use the seismic channel in intraspecific communication, possibly as an alternative to the airborne channel, which often is cluttered with noise and interference. Using the frog's vocalizations as our assay, we set out to test that pro...