Meeting Abstract
Fish use their lateral line system to maintain position and speed within a school. They also use vision for schooling because fish without a functional lateral line system can still school, as long as they can see. However, this conclusion was based on an experiment in which only the posterior lateral line system was disabled, leaving the anterior lateral line system intact. In this study, we examined schooling behavior in fish immediately after their lateral line systems were completely ablated and at weekly intervals while this system regenerated. We filmed groups of giant danios (Devario aequipinnatus, 5 fish/group) with two high-speed cameras and reconstructed the 3D positions of each fish within a group. One fish in the school was treated with gentamycin, an aminoglycoside antibiotic that is toxic to hair cells located in neuromasts. Fluorescent staining of the lateral line system showed complete ablation of both the canal and superficial neuromasts from the antibiotic treatment, and full regeneration of the hair cells after one week. As the treated fish swam within the school, we quantified the overall structure of the school by calculating the nearest neighbor distance, bearing, elevation, and angular velocity correlations between each pair of nearest neighboring fish. We found that the treated fish were able to maintain a normal position within the school immediately after the lateral line ablation, but these fish could not school normally one week after treatment while the hair cells in the neuromasts were regenerating. By eight weeks post-treatment, the treated fish could again school normally. These results suggest that fish may need more time than previously thought to relearn how to process signals from newly regenerated hair cells of the lateral line system.
