Function of lateral line canal morphology

Abstract

Fish perceive water motions and pressure gradients with their lateral line. Lateral line information is used for prey detection, spatial orientation, predator avoidance, schooling behavior, intraspecific communication and station holding. The lateral line of most fishes consists of superficial neuromasts (SNs) and canal neuromasts (CNs). The distribution of SNs and CNs shows a high degree of variation among fishes. Researchers have speculated for decades about the functional significance of this diversity, often without any conclusive answers. Klein et al. (2013) examined how tubules, pore number and pore patterns affect the filter properties of lateral line canals in a marine teleost, the black prickleback (Xiphister atropurpureus). A preliminary mathematical model was formulated and biomimetic sensors were built. For the present study the mathematical model was extended to understand the major underlying principle of how canal dimensions influence the filter properties of the lateral line. Both the extended mathematical model and the sensor experiments show that the number and distribution of pores determine the spatial filter properties of the lateral line. In an environment with little hydrodynamic noise, simple and complex lateral line canals have comparable response properties. However, if exposed to highly turbulent conditions, canals with numerous widely spaced pores increase the signal to noise ratio significantly.

The mechanosensory lateral line is used to assess opponents and mediate aggressive behaviors during territorial interactions in an African cichlid fish

“…While A. burtoni are found in shallow shore pools of Lake Tanganyika, genetic techniques have classified them as a riverine species (Brawand et al, 2014), and the narrow canal morphology is consistent with river-dwelling fish. The more turbulent environment of rivers creates hydrodynamic noise, and the narrow canal morphology and small pore diameter help reduce noise to better detect relevant signals (Klein and Bleckmann, 2015). The distribution of cranial neuromasts in A. burtoni is consistent with all previously examined African cichlids, independent of whether they possess widened or narrow canals Bird and Webb, 2014).…”

Micro-Machined Flow Sensors Mimicking Lateral Line Canal Neuromasts

“…The results of the FEM revealed that the output signals of neighboring sensors can only be used for the calculation of flow velocity for certain canal shapes (see also [70,71,84,85]; see [86] for sensory hairs of cricket cerci). In our proof of principle study, the larger lamellae produced in thick-film technology were located in one wide "end-to-end main canal structure" featuring small pores.…”

Structure and function of the mechanosensory lateral line system in fish and biomimetic

“…The biologists have been speculated the function of the CNM, the co-relationship of the canal morphology and fish habits over decades. Until recently, the mathematic model and the device of artificial lateral line receptor established by Klein and Bleckmann (2015), demonstrate that "it is possible to change the transfer function of an artificial line by changing its canal shape, dimensions and pore pattern". Moreover, their research evident indicate that the lateral line is able to "detect and localize vibrating sources, detect and monitor vortices, localize upstream objects, discriminate between upsteam objects (size and shape), estimate bulk flow velocity in turbulent environment, and measure small amounts of liquid" (Klein, 2016 personal communication).…”