Sound detection by the American lobster (Homarus americanus) [RESEARCH ARTICLE]

Youenn Jezequel, Ian T. Jones, Julien Bonnel, Laurent Chauvaud, Jelle Atema, and T. Aran Mooney
Although many crustaceans produce sounds, their hearing abilities and mechanisms are poorly understood, leaving uncertainties regarding whether or how these animals use sound for acoustic communication. Marine invertebrates lack gas-filled organs required for sound pressure detection, but some of them are known to be sensitive to particle motion. Here, we examined whether the American lobster (Homarus americanus) could detect sound and subsequently sought to discern the auditory mechanisms. Acoustic stimuli responses were measured using auditory evoked potential (AEP) methods. Neurophysiological responses were obtained from the brain using tone pips between 80 and 250 Hz, with best sensitivity at 80–120 Hz. There were no significant differences between the auditory thresholds of males and females. Repeated controls (recordings from deceased lobsters, moving electrodes away from the brain and reducing seawater temperature) indicated the evoked potentials' neuronal origin. In addition, AEP responses were similar before and after antennules (including statocysts) were ablated, demonstrating that the statocysts, a long-proposed auditory structure in crustaceans, are not the sensory organs responsible for lobster sound detection. However, AEPs could be eliminated (or highly reduced) after immobilizing hairfans, which cover much of lobster bodies. These results suggest t...

Source: Journal of Experimental Biology - March 25, 2021 Category: Biology Authors: Jezequel, Y., Jones, I. T., Bonnel, J., Chauvaud, L., Atema, J., Mooney, T. A. Tags: RESEARCH ARTICLE Source Type: research