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Voltage of an Electric Eel

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Bibliographic Entry Result
(w/surrounding text)
Kent, George C. Comparative Anatomy of the Vertebrates. USA: Mosby Year Book, 1992. "the potential produced by these organs in eels amounts to 600 volts" 600 V
"Electric Eel." Encyclopedia Britannica. Britannica. 1997: 426. "the shock… can measure up to 650 volts" 650 V
Great Book of Animals. USA: Courage Books. 1997. "and the other of a high voltage, 100 V in specimens of about four inches (10 cm) and 500 V in those over 3 feet (1 m)" 100–500 V
Whitfield, Phillip. "Electric Eel." MacMillan Illustrated Animal Encyclopedia. New York: MacMillan, 1984: 512. "which produces a charge… which may amount to 500 V" 500 V

The electric eel (Electrophorus electricus), which is found in South American tropical regions, has the ability to produce powerful electric charges. The low intensity charges emitted by the eel range from 5 to 10 V. The higher intensity charges vary by the size of the eel. Smaller eels (about 10 cm in length) can produce charges of up to 100 V. Larger eels (over 1 m in length) can produce charges of 450 to 650 volts of electricity. The discharging system of the electric cells was first explained by a Martins-Ferreira, Altamirano and Keynes in 1953.

The electric organs of the eel are located in its tail, which is roughly 4/5 of the animal's body. The electric organs are made up of a large number of electric disks (as many as 200,000 in one tail) piled in vertical or horizontal rows. The nerve endings located at the end of the electroplax discharge the electricity.

The electric organs are used many different ways by the electric eel. The low intensity impulses are used by the eel for sensory perception. This helps it navigate in its habitat (muddy streams) where vision is blocked. The low intensity impulses are also used for communication. The high intensity charges are used for stunning or killing smaller fish. The charge is also used for the eel to defend itself.

The electric eel is one of the few animals on the planet that can make, store, and discharge electricity. The actual amount it discharges is debatable. However, 500 V is the most accepted value to express the electric current produced by an electric eel.

Barry Lajnwand -- 1999

Bibliographic Entry Result
(w/surrounding text)
The New Book of Popular Science 4th ed. China: Grolier, 1978. "Gymnotid eels of the genus Electrophorous can produce charges of over 500 volts" 500 V
"Electric Eel." World Book Encyclopedia. Chicago: World Book, 1997. "Each electroplaque gives off a small charge of electricity…. The charges [sic] of all these electroplaques combine to produce 350–650 V." 350–650 V
Argo, Joseph. Electric Eel. MAD Scientist Network. Washington University Medical School. 28 August 1997. "They generally release a charge [sic] of about 25-75 volts but can get as powerful as 500 volts (some have been reported to be up to 800 volts, but this is an unconfirmed report)" 25–75 V
500 V
800 V
Prappas, Jim. Electric Eel. Pittsburgh Zoo. "Feeding: Eat other fish, killing them with electric shock (up to 600 Volts)." 600 V

The electric eel (Electrophorous electricus) is not considered a true eel. Although it looks like other eels, it is quite different. The electric eel has different habits, and is commonly known for its ability to generate an electric current. It is a spineless, toothless fish that grows up to three feet long and is found in the Amazon and other South American rivers.

The characteristics of the electric eel which makes it unique, is the electric voltage that it produces. The body of the electric eel is mostly made up of an organ that produces electricity. Like a battery the electric eel has two opposite poles (the head and the tail), and when they discharge, the voltage flows from either the head or the tail.

The organ in the electric eel that enables it to produce electricity is made up of 5,000 to 6,000 electroplaques (set up much like the cells in a dry battery). Each electroplaque produces only a small voltage, but when all the electroplaque are all arranged in series (as they are in the body of the electric eel) you get a large jolt. It can produce voltages of up to 500 to 650 volts. This is five times the voltage that comes out a wall socket, and is strong enough to injure or even kill a human.

The question that remains to be answered is, why does the electric eel have this strange ability? The answer is quite simple, the electric eel uses it ability to produce electricity to hunt for food. The charge from the eel kills its prey allowing the electric eel to swallow it. They need to do this because they have no teeth, and can only feed on prey that is not moving. Although the electric eel can produce large voltages it is the current that kills and not the voltage.

Dafe Okodiko -- 1999

Bibliographic Entry Result
(w/surrounding text)
"Electric Fish." Encyclopedia Americana. "The electric eel (Electrophorous electricus) can produce a discharge of over 500 volts (at about one ampere) and the fresh water African catfish (Malapterurus electricus) produces about 350 volts." 500 V
Allen, Missy & Michael Peissel. Dangerous Water Creatures. New York: Chelsea House, 1992: 40. "These organs emit two kinds of discharges, one of the high voltage (550 volts) for stunning prey and one that is much weaker…." 550 V
 Guinness Book of Records. New York: Bantam, 1992: 95. "The most powerful electric fish is the electric eel, which is found in the rivers of Brazil, Columbia, Venezuela, and Peru. An average size specimen can discharge 400 volts at 1 amp, but measurements up to 650 volts have been recorded." 400 V
Electric Fish. The Funk & Wagnalls Encyclopedia. "They are capable of emitting a discharge of 450-600 volts." 450–600 V

Electric eels are not eels. They are fish of the family Gymnotidae. They can produce electric currents. These serpentine fish can produce paralyzing discharges with their powerful electric organs. The powerful electric organs lie on either side of the vertebral column. These electric organs have around 5,000 to 6,000 electroplates which are arranged like cells in a battery. The organ emits 2 kinds of discharges, a high voltage one and a weaker one. The high voltage discharge can go up to around one ampere at 500 volts. It is usually for stunning prey. The weaker discharge is used for direction and as an indicator for locating objects. Electric eels have been known to knock down a horse crossing a stream from 20 feet away not to mention also killing humans. They are also known to still emit discharge eight to nine hours after their death. The shock from an electric eel affects the body by altering physiological functions such as involuntary muscle actions and respiration. Symptoms of being shocked by an electric eel can be respiratory paralysis and cardiac failure. These symptoms may result in death.

Sunny Feng -- 2000

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