Conrad Naber Lecture Hall
International University Bremen Campus Ring 1 28759 Bremen
Fish use the mechanosensory lateral line to detect weak water motions and steep pressure gradients. The lateral line system of fish consists of superficial neuromasts and of neuromasts embedded in lateral line canals. The lateral line system shows a high morphological diversity that most likely reflects an adaptation to the hydrodynamic environment a fish lives in (e.g. still water versus running water) and to the style of fish locomotion (e.g. slow swimmer versus fast swimmer). Fish may have only a few or many thousand neuromasts. Lateral line canals may be straight or highly branched, they may have no or many tubuli. Under natural conditions the fish lateral line is stimulated by water motions caused by conspecifics, predators, or prey. In addition many running water fish are constantly exposed to laminar or turbulent water flow caused by abiotic sources. During the first half of my talk I will speak about the behavioral significance of the lateral line. I will show that fish use lateral line information for the detection, discrimination and localization of stationary and moving objects and for the building of spatial cognitive maps. The second half of my talk will summarize our knowledge about the peripheral and central processing of lateral line information. I will show why fish - even if exposed to hydrodynamic noise - can sense and discriminate meaningful minute water motions. Finally I will point out that the fish lateral line can be used as a model for the building of miniaturized artificial flow sensors.