Generator fish, or “living” electricity

In wildlife, there are many processes associated with electrical phenomena. Let's consider some of them.

Many flowers and leaves have the ability to close and open depending on the time and day. This is due to electrical signals representing an action potential. You can make the leaves close with external electrical stimuli. In addition, damage to currents occurs in many plants. Slices of leaves, stems are always negatively charged in relation to normal tissue.

If you take a lemon or an apple and cut it, and then attach two electrodes to the peel, they will not reveal the potential difference. If one electrode is applied to the peel, and the other to the inside of the pulp, then a potential difference will appear, and the galvanometer will notice the appearance of amperage.

The change in the potential of some plant tissues at the time of their destruction was investigated by the Indian scientist Bos. In particular, he connected the external and internal parts of the pea with a galvanometer. He heated a pea to a temperature of up to 60 ° C, while an electric potential of 0.5 V was recorded. The same scientist investigated the mimosa pad, which he irritated with short current pulses.

With irritation, an action potential arose. The mimosa reaction was not instantaneous, but with a delay of 0.1 s. In addition, another type of excitation propagated in the pathways of the mimosa, the so-called slow wave that occurs during damage. This wave passes by the little hearts, reaching the stem, causing the appearance of an action potential that is transmitted along the stem and leading to the lowering of nearby leaves. Mimosa reacts with the movement of the sheet to irritation of the pads with a current of 0.5 μA. The sensitivity of a person’s tongue is 10 times lower.

No less interesting phenomena associated with electricity can be found in fish. The ancient Greeks were wary of meeting fish with water, which made animals and people numb. This fish was an electric ramp and but the force is the name torpedo.

In the life of different fish, the role of electricity is different. Some of them with the help of special organs create powerful electric discharges in water. So, for example, freshwater eel creates a tension of such strength that it can repel an enemy attack or paralyze the victim. The electrical organs of the fish are made up of muscles that have lost the ability to contract. Muscle tissue serves as a conductor, and connective tissue serves as an insulator. The nerves from the spinal cord go to the organ. But in general, it is a small-plate structure of alternating elements. The eel has from 6,000 to 10,000 connected in series elements forming a column, and about 70 columns in each organ located along the body.

For many fish (gymnasium, fish knifes, gnatonemus) the head is charged positively, the tail is negative, but for electric catfish, on the contrary, the tail is positive and the head is negative. The fish use their electrical properties for both attack and defense, as well as to search for a victim, navigate in troubled waters, and identify dangerous opponents.

There are also low-electric fish. They do not have any electrical organs. These are ordinary fish: crucians, carps, minnows, etc. They sense an electric field and emit a weak electric signal.

First, biologists discovered the strange behavior of a small freshwater fish - American catfish. He felt a metal stick approaching him in water at a distance of several millimeters.The English scientist Hans Lissman encased metal objects in a paraffin or glass shell, dipped them in water, but he failed to deceive the Nile catfish and gymnarchus. The fish felt metal. Indeed, it turned out that fish have special organs that perceive a weak electric field.

Checking the sensitivity of electroreceptors in fish, scientists conducted an experiment. They closed the aquarium with a fish with a dark cloth or paper and drove nearby in the air with a small magnet. The fish felt a magnetic field. Then the researchers simply drove near the aquarium with their hands. And she reacted even to the weakest bioelectric field created by the human hand.

Fish are not worse, and sometimes better than the most sensitive devices in the world, register an electric field and notice the slightest change in its intensity. Fish, as it turned out, are not only floating “galvanometers”, but also floating “electric generators”. They radiate an electric current into the water and create an electric field around them, much larger in strength than arising around ordinary living cells.

With the help of electrical signals, fish can even “talk” in a special way. Acne, for example, at the sight of food begins to generate current pulses of a certain frequency, thereby attracting its counterparts. And if two fish are placed in one aquarium, the frequency of their electric discharges immediately increases.

Fish rivals determine the strength of their opponent by the strength of the signals emitted by him. Other animals do not have such feelings. Why are only fish endowed with this property?

Fish live in the water. Sea water is a wonderful conductor. Electric waves propagate in it, without attenuation, for thousands of kilometers. In addition, fish have physiological features of the structure of muscles, which over time have become “living generators”.

The ability of fish to accumulate electrical energy makes them ideal batteries. If we could deal with the details of their work in more detail, there would be a revolution in technology, in terms of creating batteries. The electro-location and underwater communication of fish made it possible to develop a system for wireless communication between a fishing vessel and a trawl.

It would be appropriate to end with a statement that was written next to a regular glass aquarium with an electric slope, presented at the exhibition of the Royal British Society in 1960. Two electrodes were lowered into the aquarium, to which a voltmeter was connected. When the fish was at rest, the voltmeter showed 0 V, while the fish moved - 400 V. The nature of this electrical phenomenon, observed long before the organization of the Royal Society of England, people still can not unravel. The mystery of electrical phenomena in living nature still excites the minds of scientists and requires its solution.