What primary function do lateral lines serve in fish?

Lateral lines are specialized sensory structures found in fish and some amphibians that serve primarily to detect sound and vibrations in the water. This unique system consists of a series of fluid-filled canals lined with sensory hair cells, which are sensitive to changes in water pressure and movement. By sensing these alterations, fish can perceive their surroundings, navigate through the water, and detect potential predators, prey, and environmental changes.

The ability to detect vibrations allows fish to respond quickly to their environment, which is crucial for survival. For example, they can adjust their movements in response to the presence of other animals or obstacles, helping them avoid danger or locate food effectively. Overall, the lateral line system plays a vital role in a fish's ability to thrive in aquatic ecosystems.