Meeting Abstract
Schooling fish use multiple sensory systems to maintain position and speed within a school, and disabling their flow sensing lateral line system is known to alter schooling behavior. The lateral line contains two parts: an anterior portion that is affected mostly by oncoming flow as the fish swims forward, and a posterior portion that is more affected by the side-to-side swimming movement. Therefore, the two portions may have different roles in maintaining behaviors, including schooling, navigating around complex obstacles, foraging, mating, and predator detection. In this study, we examined schooling behavior in fish immediately after we ablated only their anterior lateral line, only the posterior, or the complete lateral line systems, and we tracked the behavior at weekly intervals after the system regenerated. We filmed schools of five giant danios, Devario aequipinnatus, with two high-speed cameras and reconstructed the 3D positions of each fish within a school. We found that fish with any of the three ablation treatments were able to maintain a normal position within the school immediately after treatment. However, fish with their anterior or entire lateral line system ablated could not school normally one and two weeks after treatment, even though the hair cells regenerated, but those with the posterior lateral line ablated were able to school normally. Within the school, control fish generally synchronize tail beats. Immediately after treatment, all fish have difficulty maintaining tail beat synchrony. The effect persists for much longer for fish with the posterior lateral line ablation, compared with those that have the anterior ablation. By four weeks post-treatment, all treated fish could again school normally. These results indicate that the anterior and posterior lateral line serve different functional purposes during schooling.
