111.3 Lateral Line Research:
the Importance of Using Natural Stimuli in
Studies of Sensory Systems
Horst Bleckmann, Joachim Mogdans and Guido Dehnhardt
Institut ftir Zoologie, Universitat Bonn, Poppelsdorfer Schlol3, 53115 Bonn,
Germany
Abstract
The mechanosensory lateral line is a hydrodynamic receptor system which allows
fishes and some aquatic amphibians to detect minute water motions generated by
conspecifics, predators, or prey. The sensory units of the lateral line, the neuromasts, can occur free-standing on the surface of the skin or embedded in lateral
line canals. The morphological design of the peripheral lateral line varies across
species and has long been thought to represent an adaptation to the hydrodynamic
conditions that prevail in the habitat of a given species. This chapter argues that in
order to fully comprehend lateral line information processing it is imperative to
take into account the ecology of fishes, meaning that natural stimulus and noise
conditions have to be considered. In all previous studies on lateral line function
sinusoidal water motions were applied to a stationary fish in a low-noise environment, a highly unnatural situation. Thus, these studies have not revealed specialized form-function relationships. However, data from our laboratory indicate that
morphological and physiological spezializations of the lateral line system can be
correlated when experiments are performed in which the natural situation of fishes
is considered, for instance when the lateral line is tested with hydrodynamic
stimuli applied under different background noise conditions.
Key words Lateral line, mechanoreception, fish, ecology, sensory physiology
1 Introduction
Extant fishes constitute about half the total number of all living vertebrates. Most
vertebrates - including fish -have a well-developed olfactory, auditory, and visual
system. Some fish lack a visual system, others, like Gymnotidae and Siluridae,
have an additional electrosensory system. All extant fishes and most aquatic
amphibians possess a hydrodynamic sensory system, the mechanosensory lateral
line. Thus the lateral line is one of the most important sensory systems of aquatic
anamniotes.
the Importance of Using Natural Stimuli in
Studies of Sensory Systems
Horst Bleckmann, Joachim Mogdans and Guido Dehnhardt
Institut ftir Zoologie, Universitat Bonn, Poppelsdorfer Schlol3, 53115 Bonn,
Germany
Abstract
The mechanosensory lateral line is a hydrodynamic receptor system which allows
fishes and some aquatic amphibians to detect minute water motions generated by
conspecifics, predators, or prey. The sensory units of the lateral line, the neuromasts, can occur free-standing on the surface of the skin or embedded in lateral
line canals. The morphological design of the peripheral lateral line varies across
species and has long been thought to represent an adaptation to the hydrodynamic
conditions that prevail in the habitat of a given species. This chapter argues that in
order to fully comprehend lateral line information processing it is imperative to
take into account the ecology of fishes, meaning that natural stimulus and noise
conditions have to be considered. In all previous studies on lateral line function
sinusoidal water motions were applied to a stationary fish in a low-noise environment, a highly unnatural situation. Thus, these studies have not revealed specialized form-function relationships. However, data from our laboratory indicate that
morphological and physiological spezializations of the lateral line system can be
correlated when experiments are performed in which the natural situation of fishes
is considered, for instance when the lateral line is tested with hydrodynamic
stimuli applied under different background noise conditions.
Key words Lateral line, mechanoreception, fish, ecology, sensory physiology
1 Introduction
Extant fishes constitute about half the total number of all living vertebrates. Most
vertebrates - including fish -have a well-developed olfactory, auditory, and visual
system. Some fish lack a visual system, others, like Gymnotidae and Siluridae,
have an additional electrosensory system. All extant fishes and most aquatic
amphibians possess a hydrodynamic sensory system, the mechanosensory lateral
line. Thus the lateral line is one of the most important sensory systems of aquatic
anamniotes.