Fish Produce the Electric Shock!

 Its an amazing things that can fish or Eel generates the electric Shock!

The electric eel, Electrophorus electricus, is a species of fish. It is capable of generating powerful electric shocks, which it uses for both hunting and self-defense. It is an apex predator in its South American range. Despite its name it is not an eel at all but rather a knifefish.


A typical electric eel has an elongated square body, a flattened head, and an overall dark grayish green color shifting to yellowish on the bottom. They have almost no scales. The mouth is square, placed right at the end of the snout. The anal fin continues down the length of the body to the tip of their tail. It can grow up to 2.5 m (about 8.2 feet) in length and 20 kg (about 44 pounds) in weight, making them the largest Gymnotiform.1 m specimens are more common.

Physical Description

Electric eels are not really eels, they are actually ostariophysians, but have a strong physical resemblance to true eels. The body is long and snake-like, lacking caudal, dorsal and pelvic fins. Body length can be as long as 2.5 m. They also have an extremely elongated anal fin, which is used as a means of locomotion. It is cylindrical in shape with a slightly flattened head and large mouth. The vital organs to the fish are all in the anterior portion of the body and only take up about 20 percent of the fish. The posterior portion of the body contains the electrical organs. They do have gills, though it is not their primary source of oxygen intake. Electric eels are obligatory air breathers. They receive almost 80 percent of their oxygen through their highly vascularized mouth. A thick, slimy skin covers the entire body of E. electricus. The skin is used as a protective layer, often from their own electrical current that is produced. Electric eels range from gray to brownish/black in color with some yellowish coloration on the anterior ventral portion of the body.


Although electric eels have the potential to be fairly aggressive animals, they are not. They really only use their strong electric organ discharges for predation and defensive purposes. Weak electric organ discharges are used for electrolocation as well as identification of foreign objects. This is especially important because of their poor eyesight. They are nocturnal animals that live in muddy dark waters, so they must rely on electricity for sensing. Electric eels tend to stay relatively rigid in order to fully use their electrical capabilities. They have a positive charge near the head, while the tail end is negative. When scanning their environment with electric current, they begin at the tail and finish with the head. In order to do this the fish must be able to swim backward. The polarity of the fish itself helps to create this electric field that dictates much of the animal’s behavior.

The use of electrical organs has been studied in great detail. From many different experimental situations it is clear that the eels are able to detect an electrical circuit in the water and differentiate between a closed and an open system. It has also been determined that electric eels are very sensitive to the changes in water conductivity. It is the electroreception system that allows them to navigate through the muddy dark waters they dwell in.


he electric eel has three abdominal pairs of organs that produce electricity. They are the main organ, the hunter's organ, and the sachs’ organ. These organs take up 4/5 of its body. Only the front 1/5 contains the vital organs. These organs are made of electrocytes lined up in series. The electrocytes are lined up so the current flows through them and produces an electrical charge. When the eel locates its prey, the brain sends a signal through the nervous system to the electric cells. This opens the ion channel, allowing positively-charged sodium to flow through, reversing the charges momentarily. By doing that it creates electricity. The electric eel generates its characteristic electrical pulse in a manner similar to a battery, in which stacked plates produce an electrical charge. In the electric eel, some 5,000 to 6,000 stacked electroplaques are capable of producing a shock at up to 500 volts and 1 ampere of current (500 watts). The organs give the electric eel the ability to generate two types of electric organ discharges (EODs), low voltage and high voltage. The shock could be harmful for an adult human.

The Sachs organ is associated with electrolocation. Inside the organ are many muscle-like cells, called electrocytes. Each cell can only produce 0.15V, though working together the organ transmits a signal of about 10V in amplitude at around 25 Hz. These signals are what is thought to be used for communication as well as orientation; useful not only for finding prey, but also in finding and choosing a mate.

High-voltage EODs are emitted by the main organ and the Hunter's organ that can be emitted at rates of several hundred Hz. These high voltage EODs may reach up to 650 volts. The electric eel is unique among the gymnotiforms in having large electric organs capable of producing lethal discharges that allows them to stun prey. There are reports of animals producing larger voltages, but the typical output is sufficient to stun or deter virtually any other animal. Juveniles produce smaller voltages (about 100 volts). Electric eels are capable of varying the intensity of the electrical discharge, using lower discharges for "hunting" and higher intensities for stunning prey, or defending themselves. When agitated, it is capable of producing these intermittent electrical shocks over a period of at least an hour without signs of tiring. The species is of some interest to researchers, who make use of its acetylcholinesterase and ATP.

The electric eel also possesses high-frequency sensitive tuberous receptors patchily distributed over the body that seem useful for hunting other gymnotiforms.


Electric eel-Wikipedia


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