Electric fishes
Electric fishes produce shocks of electricity to stun their prey and to defend themselves from attacks. The shocks are produced by special muscles that may take up a large part of the fish's body. Instead of producing movement, like ordinary muscles, these muscles produce electric impulses. The impulses are strong enough to paralyze prey such as fishes, frogs and crustaceans, and to keep enemies at bay.
The electric eel is the most powerful electric fish. It lives in rivers in South America, and grows to a length of over seven feet. It cannot see very well and sends out weak electric impulses to help locate objects. When attacking its prey, it produces shocks of 200 to 300 volts at a current of a half to one ampere - enough to stun a man, though not to kill him.
Other electric fishes are not quite so powerful. The gymnotus is an eel-like fish also of South American rivers. The electric catfish lives in African rivers and the electric ray in the eastern Atlantic Ocean and the Mediterranean Sea.

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