Electrical
attack and defense
Although
most electric fishes generate only mild electric fields for communication and
sensory purposes, others can generate currents strong enough to stun prey or
ward off predators. The electric organs of an electric ray Torpedo(Torpedinidae)
have about 45 columns of electrocytes (700 per column). The columns are oriented
dorsoventrally and the current is released dorsally because the dorsal surface
of the organ and the overlying skin have lower resistance than the surrounding
tissues. Torpedo can generate a discharge of 20–50 volts and several
amps in sea water (Feng 1991),and stun prey 15 cm away (see Subclass Elasmobranchii).The Electric Eel Electrophorus
(Electrophoridae),not a true eel but a close relative of the South
American knife fishes, can generate pulses of 400 volts, or 1 amp (see Feng
1991) with its several electric organs, the largest of which consists of about
1000 electrocytes. These organs are embedded in the fish’s lateral musculature.
The two electric organs of the electric catfishes (Malapteruridae) are located
on either side of the body and each contains several millionelectrocytes. These
organs generate a current of about 300 volts. Other fishes that emit strong
electric currents includethe stargazers (Astroscopus, Uranoscopidae), in
which electroplaquesare derived from ocular muscles.
Related Topics
Privacy Policy, Terms and Conditions, DMCA Policy and Compliant
Copyright © 2018-2024 BrainKart.com; All Rights Reserved. Developed by Therithal info, Chennai.