For everyone and everything. The most powerful discharge - electric eel Electric eel how many volts
Physics in the animal world: the electric eel and its "power plant"
Electric eel(Source: youtube)
The electric eel fish (Electrophorus electricus) is the only representative of the genus Electrophorus. It is found in a number of tributaries of the middle and lower reaches of the Amazon. The body size of the fish reaches 2.5 meters in length and weighs 20 kg. The electric eel feeds on fish, amphibians, if you're lucky - birds or small mammals. Scientists have been studying the electric eel for tens (if not hundreds) of years, but only now some features of the structure of its body and a number of organs have begun to become clear.
And the ability to generate electricity isn't the only unusual feature of an electric eel. For example, he breathes atmospheric air. This is possible thanks to a large number special kind fabrics oral cavity riddled with blood vessels... To breathe, eels need to float to the surface every 15 minutes. He cannot take oxygen from the water, since he lives in very turbid and shallow reservoirs, where there is very little oxygen. But, of course, the main one distinctive feature the electric eel is its electrical organs.
They play the role of not only a weapon for stunning or killing its victims, which the eel feeds on. The discharge generated by the electric organs of the fish can be weak, up to 10 V. Such discharges are generated by the eel for electrolocation. The fact is that fish have special "electroreceptors" that allow detecting distortions electric field caused by it own body... Electrolocation helps the gloom find its way into muddy water and find hidden victims. Eel can give a strong discharge of electricity, and at this time a lurking fish or amphibian begins to twitch chaotically due to seizures. The predator easily detects these vibrations and eats the prey. Thus, this fish is both electroreceptive and electrogenic at the same time.
It is interesting that eel generates discharges of various strengths with the help of three types of electrical organs. They occupy about 4/5 of the length of the fish. High voltage is generated by the organs of Hunter and Maine, and small currents for navigation and communication purposes are generated by the Sachs organ. The main organ and Hunter's organ are located in the lower part of the eel's body, Sachs's organ in the tail. Eels communicate with each other using electrical signals at a distance of up to seven meters. With a certain series of electrical discharges, they can attract other individuals of their species to themselves.
How does an electric eel generate an electrical discharge?
Eels of this species, like a number of other "electrified" fish, reproduce electricity in the same way as nerves and muscles in the organisms of other animals, only for this they use electrocytes - specialized cells. The task is performed using the enzyme Na-K-ATPase (by the way, this enzyme is also very important for mollusks of the nautilus genus (lat. Nautilus)). Thanks to the enzyme, an ion pump is formed, pumping sodium ions out of the cell and pumping in potassium ions. Potassium is removed from cells thanks to special proteins that make up the membrane. They form a kind of "potassium channel" through which potassium ions are removed. Inside the cell accumulate positively charged ions, outside - negatively charged. An electrical gradient arises. The potential difference as a result reaches 70 mV. In the membrane of the same cell of the electric organ of the eel, there are sodium channels through which sodium ions can again enter the cell. Under normal conditions, in 1 second, the pump removes about 200 sodium ions from the cell and simultaneously transfers about 130 potassium ions into the cell. A square micrometer of the membrane can accommodate 100-200 such pumps. Usually these channels are closed, but if necessary, they open. If this happens, the chemical potential gradient causes sodium ions to enter the cells again. There is a general voltage change from -70 to +60 mV, and the cell gives a discharge of 130 mV. The duration of the process is only 1 ms. Electrical cells are interconnected by nerve fibers, the connection is serial. Electrocytes make up a kind of columns that are connected in parallel. The total voltage of the generated electrical signal reaches 650 V, the current strength is 1A. According to some reports, the voltage can even reach 1000 V, and the current strength is 2A.
Electrocytes (electrical cells) of eel under a microscope
After the discharge, the ion pump operates again and the electrical organs of the eel are charged. According to some scientists, there are 7 types of ion channels in the membrane of electrocyte cells. The location of these channels and the alternation of channel types affect the rate at which electricity is generated.
Electric battery discharge
According to a study by Kenneth Catania of Vanderbilt University (USA), an eel can use three types of discharge from its electrical organ. The first, as mentioned above, is a series of low-voltage pulses that serve for communication and navigation purposes.The second is a sequence of 2-3 high-voltage pulses with a duration of several milliseconds. This method is used by eels when hunting for hidden and lurking prey. As soon as 2-3 high voltage shocks are given, the muscles of the lurking victim begin to contract and the eel can easily detect potential food.
The third method is a series of high-voltage high-frequency discharges. The third method is used by the eel when hunting, giving out up to 400 impulses per second. This method paralyzes almost any small and medium-sized animal (even a human) at a distance of up to 3 meters.
Who else is capable of generating electric current?
Of the fish, about 250 species are capable of this. For most, electricity is only a means of navigation, as in the case of the Nile elephant (Gnathonemus petersii).But only a few fish are capable of generating a sensitive electrical discharge. These are electric rays (a number of species), electric catfish and some others.
Electric catfish (
Talk about electric fish. How much current do they generate?
Electric catfish.
Electric eel.
Electric Stingray.
V. Kumushkin (Petrozavodsk).
Among electric fish, the dominance belongs to the electric eel, which lives in tributaries of the Amazon and other rivers in South America. Adult eels reach two and a half meters. The electrical organs - the transformed muscles - are located on the sides of the eel, extending along the spine for 80 percent of the entire length of the fish. This is a kind of battery, the plus of which is in the front of the body, and the minus in the back. A living battery generates a voltage of about 350, and in the largest individuals - up to 650 volts. With an instantaneous current strength of up to 1-2 amperes, such a discharge is capable of knocking a person off his feet. With the help of electrical discharges, the eel defends itself from enemies and gets food for itself.
In the rivers Equatorial Africa there is another fish - electric catfish. Its dimensions are smaller - from 60 to 100 cm. Special glands that generate electricity make up about 25 percent of the total weight of the fish. The electric current reaches 360 volts. There are known cases of electric shock in people bathing in the river and accidentally stepping on such a catfish. If an electric catfish falls on a fishing rod, then the angler can receive a very noticeable electric shock, which has passed along the wet fishing line and the rod to his hand.
However, skillfully directed electrical discharges can be used in medicinal purposes... It is known that the electric catfish occupied an honorable place in the arsenal. traditional medicine among the ancient Egyptians.
Electric rays are also capable of generating very significant electrical energy. There are more than 30 types of them. These sedentary bottom dwellers, ranging in size from 15 to 180 cm, are distributed mainly in coastal zone tropical and subtropical waters of all oceans. Hidden at the bottom, sometimes half immersed in sand or silt, they paralyze their prey (other fish) with a discharge of current, the voltage of which is different types stingrays are from 8 to 220 volts. A stingray can also inflict a significant electric shock on a person who accidentally comes into contact with it.
In addition to electric charges of great strength, fish are also capable of producing low-voltage, weak current. Thanks to the rhythmic discharges of a weak current with a frequency of 1 to 2000 pulses per second, they are perfectly oriented even in muddy water and signal to each other about the emerging danger. Such are the mormiruses and gymnarchs who live in the murky waters of rivers, lakes and swamps in Africa.
In general, as experimental studies have shown, almost all fish, both marine and freshwater, are capable of emitting very weak electrical discharges, which can be captured only with the help of special devices. These discharges play important role in the behavioral reactions of fish, especially those that constantly keep in large schools.
I was justly reminded in the comments that despite its name, the electric eel does not belong to the order of eels, it is closer to carp and catfish.
People learned about electric fish for a long time: back in Ancient egypt used to treat epilepsy electric stingray, the anatomy of an electric eel gave Alessandro Volta the idea of his famous batteries, and Michael Faraday, the "father of electricity", used the same eel as scientific equipment. Modern biologists know what to expect from such fish (an almost two-meter eel can generate 600 volts), in addition, it is more or less known what kind of genes form such an unusual trait - this summer a group of geneticists from the University of Wisconsin in Madison (USA) published a work with the full sequence of the electric eel genome. The purpose of "electrical abilities" is also clear: they are needed for hunting, for orientation in space and for protection from other predators. Only one thing remained unknown - how exactly the fish use their electroshock, what kind of strategy they use.
Now we will find out about this ...
First, a little about the main character.
There are many dangers lurking in the mysterious and murky waters of the Amazon. One of them is the electric eel (lat. Electrophorus electricus) - the only representative of the order of electric eels. It is found in the northeast South America and occurs in small tributaries of the middle and lower reaches powerful river Amazon.
The average length of an adult electric eel is a meter and a half, although sometimes there are three-meter specimens. Such a fish weighs about 40 kg. Her body is elongated and slightly flattened from the sides. Actually, this eel is not very similar to a fish: there are no scales, only the caudal and pectoral fins, and on top of that, it breathes atmospheric air.
Photo 3. 
The fact is that the tributaries, where the electric eel live, are too shallow and muddy, and the water in them is practically devoid of oxygen. Therefore, nature has awarded the animal with unique vascular tissues in the oral cavity, with the help of which the eel assimilates oxygen directly from the outside air. True, for this he has to rise to the surface every 15 minutes. But if an eel suddenly finds itself out of water, it can live for several hours, provided that its body and mouth are not dry.
Electric charcoal is olive brown in color, which allows it to go unnoticed for potential prey. Only the throat and the lower part of the head are bright orange, but this circumstance is unlikely to help the unfortunate victims of the electric eel. As soon as he shudders with all his slippery body, a discharge is formed, with a voltage of up to 650V (mainly 300-350V), which instantly kills all the small fish nearby. The prey falls to the bottom, and the predator picks it up, swallows it whole and smears it nearby to rest a little.
Photo 4. 
Electric eel has special organs, consisting of numerous electrical plates - modified muscle cells, between the membranes of which a potential difference is formed. Organs occupy two thirds of the body weight of this fish.
However, an electric eel can generate discharges with lower voltages - up to 10 volts. Since he has poor eyesight, he uses them as radar, for navigation and search for prey.
Electric eels can be enormous in size, reaching 2.5 meters in length and 20 kilograms in weight. They inhabit the rivers of South America, such as the Amazon and Orinoco. There they feed on fish, amphibians, birds and even small mammals.
Because electric eel metabolizes oxygen directly from atmospheric air, he has to very often rise to the surface of the water. He should do this at least once every fifteen minutes, but this usually happens more often.
To date, few cases of death are known after an encounter with an electric eel. However, multiple electrical shocks can lead to respiratory or heart failure, which can lead to drowning, even in shallow water.
Photo 5. 
His entire body is covered with special organs, which consist of special cells. These cells are connected in series with each other using nerve channels. In the front of the body, "plus", in the back "minus". Weak electricity is generated at the very beginning and, passing sequentially from organ to organ, it gains strength to strike as efficiently as possible.
The electric eel itself believes that it is endowed with reliable protection, so it is in no hurry to surrender even to a larger enemy. There were times when eels did not give way even to crocodiles, and people should avoid meeting them altogether. Of course, the discharge is unlikely to kill an adult, but the sensations from it will be more than unpleasant. In addition, there is a risk of loss of consciousness, and if you are in the water, you can easily drown.
Photo 6. 
The electric eel is very aggressive, it attacks immediately and is not going to warn anyone about its intentions. The safe distance from a meter-long eel is at least three meters - this should be enough to avoid a dangerous current.
In addition to the main organs that generate electricity, the eel has one more, with the help of which it scouts environment... This kind of locator emits low-frequency waves, which, returning, notify their owner about the obstacles ahead or the presence of suitable living creatures.
Photo 7. 
Zoologist Kenneth Catania ( Kenneth catania) from Vanderbilt University (USA), observing electric eels that lived in a specially equipped aquarium, noticed that fish can discharge their battery with three different ways... The first is low-voltage pulses intended for orientation on the ground, the second is a sequence of two-three high-voltage pulses lasting several milliseconds, and finally, the third method is a relatively long salvo of high-voltage and high-frequency discharges.
When an eel attacks, it sends out many volts at a high frequency (method number three) to the prey. Three to four milliseconds of such processing is enough to immobilize the victim - that is, we can say that the eel uses remote electric shock. Moreover, its frequency is much higher than artificial devices: for example, the remote shocker Taizer gives 19 impulses per second, while the eel - as much as 400. Having paralyzed the victim, he must, without wasting time, quickly grab it, otherwise the prey will come to its senses and float away.
Photo 8. 
In an article in Science Kenneth Catania writes that the "live stun gun" acts in the same way as an artificial analogue, causing a strong involuntary muscle contraction. The mechanism of action was determined in a kind of experiment, when a fish with a destroyed spinal cord was placed in an aquarium with an eel; they were separated from each other by an electrically permeable barrier. The fish could not control the muscles, but they contracted themselves in response to electrical impulses from the outside. (The eel was provoked to discharge by throwing worms to it as food.) If the nerve poison curare was also injected into a fish with a destroyed spinal cord, then the electricity from the eel had no effect on it. That is, the target of electrical discharges was precisely the motor neurons that control the muscles.
Photo 9. 
However, all this happens when the eel has already determined its prey. And if the prey is hidden? You won't find it by the movement of the water. In addition, the eel itself hunts at night, and at the same time cannot boast good eyesight... To find prey, he uses discharges of the second kind: short trains of two to three high-voltage pulses. Such a discharge mimics the signal of motor neurons, prompting all the muscles of a potential victim to contract. The eel, as it were, orders it to reveal itself: a muscle spasm passes through the body of the victim, it begins to twitch, and the eel catches the vibrations of the water - and understands where the prey is hidden. In a similar experiment with a fish with a destroyed spinal cord, it was separated from the eel by an electrically impermeable barrier, but the eel could feel the waves of water from it. Simultaneously, the fish was connected to a stimulant, so that its muscles contracted at the will of the experimenter. It turned out that if an eel emitted short "detection pulses" and at the same time the fish was forced to twitch, then the eel attacked it. If the fish did not respond in any way, then the eel, of course, did not react to it in any way - it simply did not know where it was.
In general, the electric eel demonstrates a rather sophisticated hunting strategy. From time to time, sending in external environment"Pseudomuscular" discharges, it forces the hidden victims to reveal themselves, then swims up to where the waves propagate in the water, and delivers another discharge, paralyzing the prey. In other words, the acne simply gains control over the muscles of the victim, ordering them to move or freeze when he needs it.
Photo 11. 
Photo 12. 
Photo 13. 
Many readers of the site about animals, the site know that there are fish that have the ability to be electrocuted (in the literal sense), but not everyone knows how this is done. We propose to consider two of the most famous marine representatives that generate current: electric stingray and electric eel. You will learn:
- is the current of these electric fish dangerous for humans;
- how the organs that generate electricity in stingray and eel are arranged;
- how stingrays and eels hunt and catch prey;
- how live fish are associated with the New Years holiday.
Electric stingray - living rechargeable battery
Electric rays are mostly small - from 50 to 60 cm, however, there are some individuals that reach a length of 2 m. Small representatives of these fish create an insignificant electric charge, and in turn large rays carry out discharges of 300 volts. The organs of an individual that produce current account for 1/6 of the body and are very developed. They are located on both sides - they take place between the fin of the chest and the head part, and can be viewed from the dorsal and abdominal parts.
The internal organs of fish, which generate electricity, have the following structure. A certain number of columns that make up the electrical plates and the bottom of the plate, like the entire organ, carries a negative charge, and the top is positively charged.
During the hunt, the stingray strikes the prey, grabbing it with fins, where the organs that produce electricity are located. During this process, an electrical charge is generated, and the prey is killed by the shock of electricity. The stingray bears similarities to a rechargeable battery... If he uses the charge in its entirety, then he will need several but then to "charge" again.
A ramp is safe without a charge, however, if it has a charge, then a person could be seriously injured by a strong electrical discharge... No fatal accidents have been identified, although the person who touched the slope may have low blood pressure, heart rhythm disturbances, and spasms, and swelling of local tissues may appear in the affected area. The stingray is inactive and mainly lives at the bottom, therefore, in order not to meet it in aquatic environment, you need to take care when in shallow water.
In the days of Ancient Rome, on the contrary, electrical discharges were recognized (and are now recognized in medicine) as health... It was believed that an electrical discharge could remove headache and relieve gout. Even today, on the shores of the Mediterranean, elderly people purposefully walk barefoot in shallow water to relieve rheumatism and gout with electric shocks.
Electric eel lit garlands on the Christmas tree
And now a note, although about fish, concerns such a holiday as New Year! It would seem like it is combined live fish and Christmas tree? That's how. Read on.
Most representatives of the electric eel group are 1 to 1.5 m long, but there are species that reach three meters. In such individuals, the impact force reaches 650 volts. People who are struck by electric shocks in water can lose consciousness and drown. Electric eel is one of the most dangerous representatives the Amazon River. The eel floats about every 2 minutes to fill the lungs with air. He is very aggressive. If you approach the eel at a distance of less than three meters, then he prefers not to take cover, but to immediately attack. Therefore, people who have seen the eel up close should quickly swim away as far as possible.
The organs of the eel responsible for the current have a similar structure to the organs of the stingray., but have a different arrangement. They represent two elongated shoots with an oblong appearance and make up 4/5 of the body of the eel as a whole and have a mass that takes up almost 1/3 of the body weight. The front of the eel is positively charged, and the back, respectively, is negative. In eels, vision decreases with old age, it is because of this that they strike their prey, emitting weak electric shocks. The eel does not attack its prey, it has a powerful enough charge to kill all small fish from an electric shock. The eel approaches its prey when it is already dead, grabs it by the head, and then swallows it.
Eels can often be seen in an aquarium, as they quickly get used to artificial conditions... Of course, keeping such fish at home is more difficult than. In order to expose their capabilities, a lamp is attached to the reservoir and the wires are lowered into the water. The light comes on during feeding. An experiment was carried out in Japan in 2010: a Christmas tree was lit using a current from an eel, which was in a special container and emitted current. Even an eel and its electric current can be beneficial if you channel the unique natural abilities of this fish in the right direction.
First, here are a few true facts about electric eels. Electric eel is not exactly an eel. The real eel is a long fish that looks a bit like a snake with fins. The electric eel is a fish of the carp order, which resembles an eel only in shape (much like a balloon resembles a soccer ball). Unlike the harmless real eels, electric eels can be very traumatic for you.
Electric eel is one of 500 electric fish species, which also include electric catfish and electric stingray.
Why do they need electricity? Imagine that you are an electric eel (if you are a large specimen, then your length can reach 3 m, and your weight - 40 kg). The water in which you live is opaque, a huge amount of debris floats in it, so even during the day it is difficult to see anything in it.
How will you find your way through the dark murky water? Different animals have developed their own mechanisms for finding their way in the dark. The bats for example, they orient themselves by sending sound signals and listening to their reflection from objects in their path. Electric eels, on the other hand, find their way in dark water using the electric fields generated by their own bodies, and this compensates for their poor vision.
The eel floats, and an electric field pulsates around it. The shape of the field changes when it stumbles upon some object that conducts current differently from water (for example, another fish, plant or stone), and special cells on the eel's body inform it about the violation of the field. Now it is clear why, even in the dark, the eel senses the objects around it.
This hypersensitivity gives the eel, like other electric fish, an advantage over other animals that have to rely on other senses: touch, taste, hearing, smell, and sight. For example, in one of the experiments, an electric fish without body contact in complete darkness found a thin glass rod 0.2 cm in diameter, which was hidden under a jar standing in water - it felt the fluctuations of its electric field, which penetrated the jar. In an electric eel, a special set of electrical organs is located along the entire length of the tail (the tail is 4/5 of the entire length of the eel, that is, 1-2 m). These organs are modified during muscle development.
Normal muscles, such as your biceps, contract with tiny electrical impulses of current. Originally, the muscles of the eel were intended for swimming in river water. But over the course of evolution, muscle fibers have transformed (now they cannot contract like our muscles) and adapted to generate electricity. They are not elongated in shape, like other muscle cells, but disc-shaped, resembling kitchen plates. These discs are lined with neurons at one end, like battery-powered bumps, and are arranged in rows one after the other. Each individual can have up to 700,000 of them. Even at rest, the eel constantly produces from 1 to 5 electrical low-voltage impulses per second. Irritate the eel - and the pulse rate will rise to 20-50 per second.
Why did electrical organs develop? In addition to performing the function of recognizing invisible objects in turbid water, electric organs also serve as a weapon for the eel. The eel uses powerful discharges to stun or even kill prey, such as fish that have swum within the range of its electric field. In addition, the electric organs are a kind of electric fence, which scares off predatory animals that had the imprudence to covet and taste it. An irritated eel can produce over 500 volts of power at 1 amp, enough to make a person pass out and a room full of light bulbs to briefly light up.
