How an electric eel produces electricity. Electric fish. How does an eel avoid electrocuting itself?

Tell us about electric fish. How much current do they produce?

Electric catfish.

Electric eel.

Electric Stingray.

V. Kumushkin (Petrozavodsk).

Among electric fish, the lead belongs to the electric eel, which lives in the tributaries of the Amazon and other rivers of South America. Adult eels reach two and a half meters. Electrical organs - 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 is in the back. A living battery produces a voltage of about 350, and in the largest individuals - up to 650 volts. With an instantaneous current of up to 1-2 amperes, such a discharge can knock a person off his feet. With the help of electrical discharges, the eel protects itself from enemies and obtains food for itself.

In the rivers Equatorial Africa another fish lives - the 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 a voltage of 360 volts. There are known cases of electric shock in people who swam in the river and accidentally stepped on such a catfish. If an electric catfish is caught on a fishing rod, then the angler can also receive a very noticeable electric shock that passes through the wet fishing line and rod to his hand.

However, skillfully directed electrical discharges can be used for medicinal purposes. It is known that the electric catfish occupied a place of honor in the arsenal traditional medicine from the ancient Egyptians.

They are also capable of generating very significant electrical energy. electric ramps. There are more than 30 species. These sedentary bottom dwellers, ranging in size from 15 to 180 cm, are distributed mainly in the coastal zone of tropical and subtropical waters of all oceans. Hiding 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 range from 8 to 220 volts. A stingray can cause a significant electric shock to a person who accidentally comes into contact with it.

In addition to high-power electrical charges, fish are also capable of generating low-voltage, weak current. Thanks to rhythmic discharges of weak current with a frequency of 1 to 2000 pulses per second, they are even in muddy water They navigate perfectly and signal each other about emerging danger. Such are the mormirus and gymnarchs, who live in the muddy 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 only be detected with the help of special devices. These ranks play important role in the behavioral reactions of fish, especially those that constantly stay in large schools.

Basic information about the electric eel :

Length: up to 2.4 m.

Weight: 45 kg.

Related species. The eel family includes 16 species, one of them being the European eel.

The color of the eel is olive-orange, the body reaches two meters in length, the head is wide and flat. The eel's electrical organs are located in the tail, the length of which is three-quarters of the entire body length.

Electric eel lifestyle

Habits: Loner.

Food: small fish, frogs, juveniles also eat invertebrates.

Lifespan: It is not known exactly how many years the electric eel lives. The oldest river eel was 88 years old, which is about the same age as the electric eel.

In the murky waters where the eel lives, visibility is poor, so it rarely relies on vision (the eel's vision is very poor). The eel receives accurate information about the surrounding world with the help of its electrical organs.

Young electric eels They catch invertebrates that live on the bottom. The fish finds prey using electrical organs that allow it to detect the prey even if it is motionless.

Sensitive sensors also record small electrical impulses that are caused by the movement of the muscles of other fish, for example, during the latter's breathing.

Once the eel detects its prey, it immediately sends out a series of electrical discharges that paralyze or even kill the victim. The eel eats only one row of small teeth, so scientists assume that it swallows its prey whole.

Electric eel breeding

Almost nothing is known about the reproduction of the electric eel. It is believed that the fry emerge from the eggs. About electrical reproduction

It is possible that, like other fish species capable of producing an electric field, eels use electrical organs to exchange information about their gender, age, and readiness to mate.

At a certain time, the eels suddenly disappear and then return, accompanied by young fish about 10 cm long. It is assumed that the fry emerge from the eggs, but this version has not been proven to this day.

Electric eel - This is the most dangerous of all electric fish. Other electric fish, such as stingrays and catfish, can produce an electrical discharge ranging from five to two hundred volts.

Electric organs. The organs that produce electricity are located in the back of the eel's body. They consist of a bundle of very thin electrical plates (EP), of which there are about 10 thousand. Each of them produces a weak electric field. When the eel activates them, the ECs produce short electrical impulses. At low voltage, electric waves are used as radar. When a fish approaches, the eel increases the intensity of the discharge and paralyzes the prey.

Places of residence. The homeland of the eel is South America. Lives in the rivers of Guyana, in the Orinoco and Amazon deltas.
Preservation. In South America, its meat is eaten, but in other regions it is not used for these purposes. The existence of the eel is only threatened by water pollution.

And dangerous, it lives in shallow muddy rivers of the northeastern part of the South American continent. It has nothing to do with common eels, being a gymnotic fish. Its main feature is the ability to generate electric charges different strengths and destinations, as well as detect electric fields.

Habitat

Over thousands of years of evolution, electric eels have adapted to survive in extreme conditions. unfavorable conditions overgrown and silted reservoirs. Its usual habitat is stagnant, warm and muddy. fresh water with severe oxygen deficiency.

The eel is breathing atmospheric air, so every quarter of an hour or more often it rises to the surface of the water to capture a portion of air. If you deprive him of this opportunity, he will suffocate. But without any harm, an eel can go without water for several hours if its body and mouth are moisturized.

Description

The electric eel has an elongated body, slightly compressed from the sides and back, and rounded in front. The color of adults is greenish-brown. The throat and lower part of the flattened head are bright orange. Characteristic- lack of scales, skin covered with mucus.

The fish grows on average up to 1.5 m in length and weighs up to 20 kg, but there are also three-meter specimens. The absence of a pelvic and dorsal fin enhances the eel's resemblance to a snake. It moves in wave-like movements using a large anal fin. Can equally easily move up and down, back and forth. Pectoral fins Small in size, they act as stabilizers when moving.

Leads a solitary lifestyle. Most spends time at the bottom of the river, frozen among thickets of algae. Eels wake and hunt at night. They feed mainly on small fish, amphibians, crustaceans, and if they are lucky, birds and small animals. The victim is swallowed whole.

Unique Feature

In fact, the ability to create electricity is not some extraordinary feature. Any living organism can do this to some extent. For example, our brain controls our muscles using electrical signals. The eel produces electricity just like the muscles and nerves in our body. Electrocyte cells accumulate a charge of energy extracted from food. Their synchronous generation of action potentials leads to the formation of short electrical discharges. As a result of the summation of thousands of tiny charges accumulated by each cell, a voltage of up to 650 V is created.

The eel emits electrical charges of various powers and purposes: impulses of protection, fishing, rest and search.

In a calm state, it lies at the bottom and does not generate any electrical signals. When hungry, it begins to swim slowly, emitting pulses of voltage up to 50 V with an approximate duration of 2 ms.

Having detected prey, it sharply increases their frequency and amplitude: the voltage increases to 300-600 V, duration - 0.6-2 ms. A series of pulses consists of 50-400 discharges. The electrical discharges sent paralyze the victim. To stun small fish, which the eel mainly feeds on, it uses high-frequency impulses. Pauses between discharges are used to restore energy.

When the immobilized prey sinks to the bottom, the eel calmly swims up to it and swallows it whole, and then rests for a while, digesting the food.

Defending itself from enemies, the eel emits a series of rare high-voltage pulses ranging from 2 to 7, and 3 small-amplitude search ones.

Electrolocation

The electric organs of eels serve not only for hunting and protection. They use weak discharges with a power of up to 10 V for electrolocation. The vision of these fish is weak, and with old age it deteriorates even more. They receive information about the world around them from electrical sensors located throughout their body. In the photo of an electric eel, its receptors are clearly visible.

An electric field pulsates around a swimming eel. As soon as any object, for example a fish, a plant, a stone, is within the sphere of action of the field, the shape of the field changes.

Catching the distortions of the electric field it creates with special receptors, it finds a path and hiding prey in the muddy water. This hypersensitivity gives the electric eel an advantage over other species of fish and animals that rely on vision, smell, hearing, touch, and taste.

Electric organs of eels

The generation of discharges of various powers is carried out by the organs different types, occupying almost 4/5 of the length of the fish. In the front part of his body there is a positive pole of the “battery”, in the tail area there is a negative one. Men's and Hunter's organs produce high-voltage impulses. Discharges for communication and navigation functions are generated by the Sachs organ located in the tail. The distance at which individuals can communicate with each other is about 7 meters. To do this, they emit a series of discharges of a certain type.

The highest eels recorded in fish kept in aquariums reached 650 V. In fish one meter long, it is no more than 350 V. This power is enough to light five light bulbs.

How eels protect themselves from electric shock

The voltage generated during hunting by an electric eel reaches 300-600 V. It is fatal to small inhabitants such as crabs, fish and frogs. And large animals, such as caimans, tapirs and adult anacondas, prefer to stay away from dangerous places. Why don't electric eels shock themselves?

The vital organs (including the heart) are located close to the head and are protected by fatty tissue, which acts as an insulator. Its skin has the same insulating properties. It has been observed that when the skin is damaged, the vulnerability of fish to electric shocks increases.

One more recorded interesting fact. During mating, eels generate very powerful discharges, but they do not cause damage to the partner. A discharge of such power, produced under normal conditions, and not during the mating period, can kill another individual. This suggests that eels have the ability to turn the electric shock defense system on and off.

Reproduction

Eels spawn with the onset of the dry season. Males and females find each other by sending impulses in the water. The male builds a well-hidden nest from saliva, where the female lays up to 1,700 eggs. Both parents take care of the offspring.

The skin of the fry is a light ocher shade, sometimes with marble stains. The first hatched fry begin to eat the rest of the eggs. They feed on small invertebrates.

Electrical organs in fry begin to develop after birth, when their body length reaches 4 cm. Small larvae are capable of generating an electric current of several tens of millivolts. If you hold a fry that is only a few days old, you can feel a tingling sensation from electrical discharges.

Having grown to 10-12 cm in length, the juveniles begin to lead an independent lifestyle.

Electric eels do well in captivity. The lifespan of males is 10-15 years, females - up to 22. How long do they live in natural environment- not known for certain.

The aquarium for keeping these fish must be at least 3 m long and 1.5-2 m deep. It is not recommended to change the water in it often. This leads to the appearance of ulcers on the body of the fish and their death. The mucus that coats the skin of acne contains an antibiotic that prevents ulcers, and frequent changes of water appear to reduce its concentration.

In relation to representatives of its species, the eel, in the absence of sexual desire, shows aggression, so only one individual can be kept in the aquarium. The water temperature is maintained at 25 degrees and above, hardness - 11-13 degrees, acidity - 7-8 pH.

Is eel dangerous for humans?

Which electric eel is especially dangerous to humans? It should be noted that meeting him is not fatal for a person, but can lead to loss of consciousness. The electrical discharge from the eel causes muscles to contract and become painfully numb. The unpleasant sensation may last for several hours. In larger individuals, the current strength is greater, and the consequences of a shock will be more dire.

This predatory fish attacks even a larger opponent without warning. If any object comes within the range of its electric field, it does not swim away or hide, preferring to attack first. Therefore, under no circumstances should you approach a meter-long eel closer than 3 meters.

Although the fish is a delicacy, catching it is deadly. Locals invented original way catching electric eels. To do this, they use cows, which can withstand electric shocks well. Fishermen drive a herd of animals into the water and wait for the cows to stop mooing and rushing about in fear. After this, they are driven onto land and begin to catch harmless eels with nets. Electric eels cannot generate current indefinitely, and the discharges gradually become weaker and stop altogether.

The family contains only one genus with a single species - the electric eel (Electrophorus electricus). Electric eels inhabit shallow rivers in the northeastern part South America and tributaries of the middle and lower Amazon.

In these low-flow, heavily overgrown, silted reservoirs, a sharp lack of oxygen often occurs. Probably, it was this circumstance that caused the electric eel to develop special areas of vascular tissue in the oral cavity, which allows it to absorb oxygen directly from the atmospheric air. To capture a new portion of air, the eel must rise to the surface of the water at least once every 15 minutes, but usually it does this somewhat more often. If an electric eel is deprived of this opportunity, it will die and, paradoxical as it may sound in relation to a fish, will drown. The electric eel's ability to use atmospheric oxygen to breathe allows it to remain out of water for several hours without any harm, but only if its body and oral cavity remain moist. This feature not only ensures the survival of eels in extremely unfavorable living conditions, but also makes them extremely convenient laboratory animals for experiments.

Electric eels are large fish average length adult individuals are 1-1.5 m, and the largest known specimen reached almost three meters in length. The electric eel has bare skin without scales; the body is strongly elongated, rounded in the anterior part and somewhat laterally compressed in the posterior part. The electric eel does not have dorsal or pelvic fins, and the pectoral fins are very small and, when the fish moves, apparently play only the role of stabilizers. The main organ of movement of the eel is the huge anal fin, numbering up to 350 rays and stretching from the anus to the end of the tail. With the help of wave-like movements of the fin, the eel can move forward and backward, up and down with equal ease.

The color of adult electric eels is olive-brown, the underside of the head and throat is bright orange, the edge of the anal fin is light, and the eyes are emerald green. The color of young fish is lighter, ocher in color, sometimes with a marbled pattern.

Most interesting feature electric eels have huge electrical organs that occupy about 4/5 of the body length. The positive pole of the “battery” lies in the front of the eel’s body, the negative - in the back, i.e., the opposite of what is the case with African electric catfish. The highest discharge voltage, according to observations in aquariums, can reach 650 V, but usually it is less, and in fish one meter long on average it does not exceed 350 V. The current strength, however, is not very high - only 0.5-0.75 Ah, so even a six-hundred-volt discharge cannot cause a fatal shock in a person. True, as the fish grows, the current strength increases significantly (up to 2 A), and it is difficult to say what the result of an electric shock from a three-meter fish may be.

The main electrical organs are used by the eel to protect itself from enemies and to paralyze its prey, which consists mainly of small fish. In addition to powerful high-voltage organs, electric eels have two more types of low-voltage organs. The purpose of one of them is unclear; all that is known is that it operates in connection with the main “battery”. The second type of “auxiliary” electrical organ plays the role of a locator, serving to detect obstacles in the path of movement, and in old fish, to search for food, since with age, the vision of electric eels apparently deteriorates sharply. The frequency of such location discharges when the fish is calm does not exceed 20-30 per second, but when excited it can reach 50.

Almost nothing is known about the reproduction and development of electric eels, like other gymnotoid fish. According to a few observations, by the time of reproduction, electric eels leave their usual habitats and return to them, accompanied by grown juveniles, which begin to lead an independent lifestyle, reaching a length of 10-12 cm.

Electric eels have been successfully kept in captivity and often decorate large public aquariums. It is not recommended to change the water in the aquarium frequently. Otherwise, electric eels develop ulcers on their bodies and die. This phenomenon is apparently due to the fact that the mucus secreted by eels contains some kind of antibiotic, which, when accumulated in the water, protects the fish from ulcerative diseases.

Electric organs are paired formations in a number of fish that are capable of generating electrical discharges; serve for defense, attack, intraspecific signaling and orientation in space. They developed independently in the process of evolution in several unrelated groups of freshwater and sea ​​fish. They were widely represented in fossil fish and jawless animals; known to more than 300 modern species. The location, shape and structure of these organs in various types varied. They can be located symmetrically on the sides of the body in the form of kidney-like formations (electric rays and electric eels) or a thin subcutaneous layer (electric catfish), thread-like cylindrical formations (mormyrids and gymnotids), in the infraorbital space (American stargazer), can be, for example, up to 1/6 (electric rays) and 1/4 (electric eels and catfish) the mass of the fish. Each organ consists of numerous electric plates collected in columns - modified (flattened) muscle, nerve or glandular cells, the membranes of which are electric generators. The number of plates and columns in the organs of different fish species is different: the electric stingray has about 600 columns arranged in the form of a honeycomb of 400 plates each, the electric eel has 70 horizontally placed columns of 6000 each, the electric catfish has electric plates, about 2 million , distributed randomly. The potential difference developed at the ends of organs when the electrical circuit, can reach 1200 V (electric eel), and the discharge power per pulse is up to 1.5 kW. The latter applies, naturally, to a closed circuit when the fish is in the water.

The electric ray Torpedo occidentalis, which lives in the ocean, also has very powerful discharges. Salty water conducts electric current better.

The discharges are emitted in series, the shape, duration and sequence of which depend on the degree of excitation and the type of fish. The repetition rate of the pulses is related to their purpose (for example, an electric stingray emits 10-12 “defense” and from 14 to 562 “hunting” pulses per second, depending on the size of the prey). The voltage in the discharge ranges from 220 (electric stingrays) to 600 V (electric eels). Fish that have electrical organs can safely tolerate voltages that kill fish that do not have them (electric eel - up to 220 V). Electrical discharges large fish dangerous to humans.

Ecology of life: Fish of the species electric eel (Electrophorus electricus) is the only representative of the genus of electric eels (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 weight - 20 kg. The electric eel feeds on fish, amphibians, and, if lucky, birds or small mammals.

The fish species electric eel (Electrophorus electricus) is the only representative of the genus of electric eels (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 weight - 20 kg. The electric eel feeds on fish, amphibians, and, 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 structural features of its body and a number of organs have begun to become clear.

Moreover, the ability to generate electricity is not the only unusual feature of the electric eel. For example, he breathes atmospheric air. This is possible thanks to a large number special type tissue of the oral cavity, riddled with blood vessels. To breathe, the eel needs to swim to the surface every 15 minutes. It cannot take oxygen from water, since it lives in very muddy and shallow bodies of water, where there is very little oxygen. But, of course, the main one distinguishing feature electric eel - these are its electrical organs.

Electric eel (Source: youtube)

They play the role of not only a weapon for stunning or killing its victims, on which the eel feeds. The discharge generated by the electrical organs of the fish can be weak, up to 10 V. The eel generates such discharges for electrolocation. The fact is that fish have special “electroreceptors” that allow them to detect distortions in the electric field caused by its own body.

Electrolocation helps the eel find its way through murky water and find hidden victims. The eel can give a strong discharge of electricity, and at this time the hidden fish or amphibian begins to twitch chaotically due to convulsions. The predator easily detects these vibrations and eats the prey. Thus, this fish is both electroreceptive and electrogenic.

Interestingly, the eel generates discharges of varying strengths using three types of electrical organs. They occupy approximately 4/5 of the length of the fish. High voltage is produced by the Hunter and Men organs, and small currents for navigation and communication purposes are generated by the Sachs organ. Main body and Hunter's organ are located in the lower part of the eel's body, Sachs' organ is 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.

How does an electric eel generate electricity?

Eels of this species, like a number of other “electrified” fish, reproduce electricity in the same way as nerves and muscles in the bodies of other animals, only for this they use electrocytes - specialized cells. The task is performed using the enzyme Na-K-ATPase (by the way, the same enzyme is very important for mollusks of the genus Nautilus (lat. Nautilus)).

Thanks to the enzyme, an ion pump is formed that pumps sodium ions out of the cell and pumps 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 excreted. Positively charged ions accumulate inside the cell, and negatively charged ones accumulate outside. An electrical gradient arises.

The resulting potential difference reaches 70 mV. In the membrane of the same cell of the eel's electrical organ there are also 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 approximately 130 potassium ions into the cell. A square micrometer of 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 flow back into the cells. There is a general voltage change from -70 to +60 mV, and the cell gives a discharge of 130 mV. The process duration is only 1 ms. Electric cells interconnect nerve fibers, the connection is serial. Electrocytes form peculiar 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 can reach 2A.

Electrocytes (electric cells) of an eel under a microscope

After the discharge, the ion pump operates again, and the eel's electrical organs are charged. According to some scientists, there are 7 types of ion channels in the membrane of electrocytic cells. The placement of these channels and the alternation of channel types affects the rate of electricity production.

SUBSCRIBE to OUR youtube channel Econet.ru, which allows you to watch online videos about human health and rejuvenation. Love for others and for yourself, as a feeling of high vibrations, is an important factor

Electric battery low

According to research by Kenneth Catania from Vanderbilt University (USA), the 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 lasting a few milliseconds. This method is used by eels when hunting hidden and hidden prey. As soon as 2-3 high voltage shocks are given, the muscles of the hidden victim begin to contract, and the eel can easily detect potential food.

SUBSCRIBE to OUR youtube channel Ekonet.ru, which allows you to watch online, video about human health improvement and rejuvenation. Love for others and for yourself, as a feeling of high vibrations, is an important factor

The third method is a series of high-voltage, high-frequency discharges. The eel uses the third method when hunting, producing up to 400 pulses per second. This method paralyzes almost any small to medium-sized animal (even humans) at a distance of up to 3 meters.

Who else is capable of generating electric current?

About 250 species of fish are capable of this. For most, electricity is just a means of navigation, as, for example, in the case of the Nile elephant (Gnathonemus petersii).

But few fish are capable of generating an electric discharge of sensitive force. These are electric stingrays (a number of species), electric catfish and some others.

Electric catfish (