Subterranean Fishes of the World

4302

2019

AIM 2019

54

Acoustic communication is an essential feature to exchange information related to social cohesion and coordination. We recently found that Astyanax mexicanus is a highly sonic species, in the laboratory and in the wild, and cave and surface morphotypes share a repertoire of at least six sounds. Based on major differences concerning eye loss and reduced aggressiveness in cavefish we hypothesised that one sound of the repertoire, the “Sharp click”, would be differentially used and have a different meaning in the two Astyanax morphs. We demonstrated that Sharp click is a visually-triggered sound produced during agonistic behaviour in surface fish and a chemosensory-triggered sound produced by cavefish during foraging behaviour. Residentintruder assays were performed in the two morphotypes to investigate relationships between Sharp clicks production and agonistic events. In addition, groups of surface fish and cavefish submitted to starvation, overfeeding or normal diets for several months were recorded during chemosensory-triggered foraging stimulation. Finally, the functional value of Sharp clicks was assessed on social groups by playing back either surface fish or cavefish Sharp clicks, or white noise.The results demonstrate that acoustic communication does exist and has evolved in blind cavefish, accompanying the evolution of its behaviours. Thus, A. mexicanus appears like a powerful model to address the question of the role of acoustic communication in evolution, and possibly speciation.

1

Astyanax Interrnational Meeting