The Lateral Line System of Fish

Abstract

Publisher Summary This chapter reviews the morphology and behavioral relevance of the lateral line system and focuses on the peripheral and central processing of lateral line information. The smallest functional unit of the lateral line system is the neuromast, a sensory structure that occurs freestanding on the skin (superficial neuromasts or SN) or in fluid‐filled canals (canal neuromasts or CN) that usually open to the environment through a series of pores. Lateral line neuromasts are composed of sensory hair cells, supporting cells, and mantle cells, which separate a neuromast from the surrounding tissue. In natural habitats, hydrodynamic stimuli are caused by inanimate and animate sources. Some fish use self‐generated water motions for lateral line perception. Some fish use capillary water surface waves for prey detection. Besides visual, acoustic, and olfactory cues, lateral line information provides the basis for many behavioral decisions. The mottled sculpin, Cottus bairdi , is a nocturnal feeder that uses the lateral line to detect prey. The lateral line is viewed as a system for close range detection. However, some predatory fish can sense and even track the hydrodynamic trail caused by prey fish. One of the most striking differences between primary lateral line afferents and central lateral line neurons are their responses to repetitive stimuli.