There are about three thousand snakes on earth. They belong to the scaly order and like to live in places warm climate. Many, walking through the forest in an area where snakes can live, wonder if they see us? Or should we look under our feet so as not to disturb the reptile? The fact is that among the diversity in the animal world, only the eyes of a snake are able to determine shades and colors, but their visual acuity is weak. For a snake, sight is, of course, important, but not in the same way as smell. IN old times people paid attention to the snake's eye, considering it cold and hypnotic.

How is the eye of a snake

Reptiles have very cloudy eyes. This is because they are covered with a film that changes during molting along with the rest of the skin. Because of this, snakes have poor visual acuity. As soon as reptiles shed their skin, their visual acuity immediately improves. During this period, they see the best. This is how they feel for several months.

Most people believe that all snakes are venomous. This is wrong. Large quantity species are completely harmless. Poisonous reptiles use poison only in case of danger and when hunting. It takes place both during the day and at night. Depending on this, the pupil changes its shape. So, during the day it is round, and at night it is extended into a slot. There are whip snakes with a pupil in the form of an inverted keyhole. Each eye is able to form a whole picture of the world.

For snakes, the main organ is the sense of smell. They use it as a thermolocation. So, in complete silence, they feel the warmth of a possible victim and indicate its location. Not poisonous species pounce on the prey and strangle it, some of them begin to swallow directly alive. It all depends on the size of the reptile itself and its prey. On average, the body of a snake is about one meter. There are both small and large species. Directing their gaze to the victim, they focus it. At this time, their tongue catches the slightest smells in space.

They do not have ears, but they react to every rustle. They don't have a nose, but they can sniff with their tongue. They can live for months without food and still feel great.
They are hated and deified, they are worshiped and destroyed, they are prayed to and with all this they are endlessly afraid. The Indians called them holy brothers, the Slavs - ungodly creatures, the Japanese - celestials of unearthly beauty ...
Snakes are not at all the most poisonous creatures on Earth, as most people think. On the contrary, the title of scary killer belongs to small South American leaf-climbing frogs. Moreover, according to statistics, every year more people die from bee stings than from snake stings.
snakes contrary to terrible myths about aggressive reptiles, the first to attack people and pursue them in a blind desire to sting, in fact - terribly shy creatures. Even among giant snakes, an attack on a person is an accidental and extremely rare phenomenon.


Seeing a person, the same vipers will first of all try to hide, hide, and they will definitely warn about their aggression, which is manifested, by hissing and false throws. By the way, the terrifying sweeps of the snake's tongue are not a threatening gesture at all. So the snake... sniffs the air! The most amazing way learn information about surrounding objects. In a couple of strokes, the tongue conveys the collected information to the sensitive serpentine palate, where it is recognized. And also a snake - and this coincides with Chinese myths- very prudent: she will never waste her poison in vain. She needs him herself - for real hunting and for defense. Therefore, most often the first bite is not poisonous. Even the king cobra often makes a blank bite.
It is the Indians who consider her a goddess endowed with great intelligence and wisdom.
By the way, it is cowardice that makes snakes and even spitting cobras feign death! In the face of a threat, these tricksters twist and fall on their backs, their mouths wide open and emitting unpleasant odors. All these subtle manipulations make the snake unattractive as a snack - and predators, disdainful of "carrion", go away. The Calabar boa acts even wiser: its blunt tail is very similar to the head. Therefore, sensing danger, the boa curls up into a ball, exposing its tail instead of a vulnerable head in front of the predator.
In fact, snakes that love to pretend to be dead are extremely tenacious creatures. There is a known case when an exhibit of a desert snake came to life in the British Museum! A copy that did not show signs of life was glued to a stand, and after a couple of years something was suspected. Peeled off, placed in warm water: the snake began to move, and then eat with pleasure and lived for another two happy years.
No matter how attractive the legends about the bewitching snake look, in fact, these reptiles do not know how to hypnotize. The look of the snake is unblinking and fixed because it has no eyelids. Instead, there is a transparent film - something like glass on a watch - protecting the eyes of snakes from bruises, injections, litter, water. And no self-respecting rabbit will succumb to the "bewitching" look and dutifully wander into the mouth of a boa constrictor: features visual system the snakes are such that they only allow her to see the outline of moving objects. Only the rattlesnake was lucky: it has three sense organs on its head that help to find prey.
The rest of the members of the creeping family have extremely poor eyesight: frozen, potential victims immediately lose sight of the hunter. By the way, most animals - and those very notorious rabbits - perfectly use this, knowing the tactics of snake hunting. From the outside - a duel of views, but in fact, the snakes have to work hard before they manage to catch someone for dinner. Is it possible to hypnotize the snakes themselves? After all, everyone knows the picture of a cobra dancing in front of the caster.
I don't want to be disappointed, but this is also a myth. The snakes are deaf and do not hear the mournful music of the pipes. But very sensitively capture the slightest fluctuations in the surface of the earth next to them. The cunning spellcaster first lightly taps the basket with the snake or stomps, and the animal immediately reacts. Then, playing a motive, he continuously moves, sways, and the snake, constantly watching him, repeats his movements so that the person is always in front of his eyes. A spectacular sight, but the hypnotist from the caster, alas, is useless.
By the way, king cobras are well versed in music. Quiet melodious sounds soothe them, and the snakes, rising, slowly sway to the beat. The abrupt, sharp sounds of jazz, especially loud, unnerve the cobra, and it uneasily inflates its "hood". Heavy and even more “metal” rock leads the “music lover” into indignation: she stands on the tail and makes quick threatening movements in the direction of the music source. Recent studies by Russian herpetologists have shown that to the classical works of Mozart, Handel and Ravel, cobras dance with obvious pleasure, closing their eyes; but pop music causes lethargy, apathy and nausea.
By the way, about snake movements: it is interesting to observe how the body of a snake moves - there are no legs, nothing pushes, does not pull, but it slides and flows, as if without bones. In fact, the fact is that snakes are simply filled with bones - in some species, up to 145 pairs of ribs can be attached to a flexible spine! The peculiarity of the snake "gait" is given by the articulated spine, to which the ribs are attached. The vertebrae are attached to each other by a kind of hinges, and each vertebra has its own pair of ribs attached, which gives a unique freedom of movement.
Some Asian snakes can fly! They can famously climb to the tops of trees and from there soar down, spreading their ribs to the sides and turning into a kind of flat ribbon. If the heavenly tree snake wants to move from one tree to another, it literally flies to it without going down. In flight they take S-shape in order to stay in the air longer and get exactly where they need to be. As strange as it may sound, the tree snake is an even better glider than flying squirrels! Some flyers can cover distances up to 100 meters in this way.
By the way, all lovers of hot rumba should be grateful to snakes. There is a curious step in the dance: the gentlemen throw their legs far to the side and, as it were, crush someone. This dance move comes from not so ancient times, when a rattlesnake in Mexican dancing was quite common. The imperturbable machos, in order to impress the ladies, crushed the uninvited guests with the heel of their boots. Then this movement became the highlight of the rumba.
Do not count the beliefs about magic power snake heart, giving strength and immortality. In fact, hunters for such a treasure would have to sweat a lot in search of this very heart: after all, it can slide along the body of a snake! This miracle is bestowed by nature in order to make it easier for the snake to pass food through the gastrointestinal tract.
Despite the reverent fear of snakes, mankind, as is known, has been using their "gifts" for healing since ancient times. But there are also more curious cases of how people - and not only - use the features of these amazing creatures. For example, owls sometimes place small snakes in their nests. They deal with small insects competing with owlets for prey brought by their mother. Thanks to the amazing neighborhood, the chicks grow faster and get sick less.
In Mexico, along with kittens and puppies, local “domestic” snakes are considered the favorites of children. They are herbivores and are covered with thick, shaggy hair. Brazilians prefer royal boas: in the houses of the suburbs of Rio de Janeiro and in the cottages of the mountain resort of Petropolis, these huge reptiles enjoy great love and respect. The fact is that in the country there are a great many poisonous snakes. But not a single poisonous individual will crawl into a garden where a boa constrictor is found, even if everything around is teeming with them. Moreover, boas are tenderly attached to children. As soon as the child leaves the house, the "nanny" begins to follow his every step. The boa constrictor invariably accompanies children on walks and during games, protecting the kids from snake attacks. Unusual governesses saved thousands of lives with their devotion, especially in countryside, where it is extremely problematic to deliver the saving serum. Kids respond to their guards with warm reciprocity: boas are very neat, always have a dry, pleasant to the touch and very clear skin, and it’s worth mentioning especially about unpretentiousness in everyday life: a boa constrictor eats once every two, or even four months, being content with an annual ration of no more than five rabbits.
And on Greek island Kefalonia snakes are not tamed, not used as a rodent exterminator or secuudica. It was on this day to miraculous icon, before which the nuns were once asked for intercession, small poisonous snakes with black crosses on their heads crawl into the temple from all around. What is amazing: they are drawn to the miraculous icon, as if spellbound, not afraid of people and not trying to bite them. People just as calmly react to unusual "parishioners" who crawl over the icons and without fear get over on their hands when they are extended to them. Even kids play with snakes. But soon after the end of the festive service, the snakes crawl off the icon of the Mother of God they love and leave the church. As soon as they crawl across the road and end up in the mountains, they again become the same: it’s better not to approach them - they will immediately hiss and bite! Yes, one can talk endlessly about these amazing creatures of nature: they stand apart in the animal world so much. And yet, in vain, for the most part, we do not like snakes so much. After all, the Chinese say that a person uses snakes with everything except hissing, and in return they receive nothing but hostility. Well, is that fair?

Thermolocators of a different design have recently been studied in snakes. This discovery deserves more details.

In the east of the USSR, from the Caspian Trans-Volga region and the Central Asian steppes to Transbaikalia and the Ussuri taiga, there are medium-sized poisonous snakes called muzzles: their heads are covered not with small scales, but with large shields.

People who have looked at muzzles up close claim that these snakes seem to have four nostrils. In any case, on the sides of the head (between the real nostril and the eye), two large (larger nostrils) and deep fossae are clearly visible in muzzles.

Cottonmouths are close relatives rattlesnakes America, which locals sometimes called kvartonaritsy, that is, four-nosed. This means that rattlesnakes also have strange pits on their faces.

All snakes with four "nostrils" are combined by zoologists into one family of so-called crotalids, or pit-headed ones. Pit snakes are found in America (North and South) and in Asia. In their structure, they are similar to vipers, but differ from them in the mentioned pits on the head.

For more than 200 years, scientists have been solving a puzzle given by nature, trying to determine what role these pits play in the life of snakes. What assumptions were made!

They thought that these were organs of smell, touch, hearing enhancers, glands that secrete lubricant for the cornea of ​​​​the eyes, traps of subtle air vibrations (like the lateral line of fish) and, finally, even air blowers that deliver oxygen to the oral cavity, allegedly necessary for the formation of poison.

Careful studies carried out by anatomists thirty years ago showed that the facial pits of rattlesnakes are not connected with either the ears, or the eyes, or

by any other known authority. They are depressions in the upper jaw. Each hole at a certain depth from the inlet is divided by a transverse partition (membrane) into two chambers - internal and external.

The outer chamber lies in front and opens outwards with a wide funnel-shaped opening, between the eye and the nostrils (in the area of ​​\u200b\u200bthe auditory scales). The rear (inner) chamber is completely closed. Only later was it possible to notice that it communicates with the external environment by a narrow and long canal, which opens on the surface of the head near the anterior corner of the eye with an almost microscopic pore. However, the size of the pore, when necessary, can apparently increase significantly: the opening is provided with an annular closing muscle.

The partition (membrane) separating both chambers is very thin (about 0.025 mm thick). Dense weaves of nerve endings permeate it in all directions.

Undoubtedly, the facial pits are the organs of some senses. But what?

In 1937, two American scientists - D. Noble and A. Schmidt published great job, in which they reported the results of their many years of experience. They managed to prove, the authors argued, that the facial pits are thermolocators! They capture heat rays and determine the location of the heated body emitting these rays by their direction.

D. Noble and A. Schmidt experimented with rattlesnakes artificially devoid of all known to science sense organs. Electric bulbs wrapped in black paper were brought to the snakes. As long as the lamps were cold, the snakes paid no attention to them. But then the light bulb warmed up - the snake immediately felt it. She raised her head, worried. The light bulb is still closer. The snake made a lightning throw and bit the warm "victim". I didn’t see her, but she bit exactly, without a miss.

Experimenters have found that snakes detect heated objects, the temperature of which is at least 0.2 degrees Celsius above the surrounding air (if they are brought closer to the muzzle itself). Warmer objects are recognized at a distance of up to 35 centimeters.

In a cold room, thermolocators work more accurately. They are obviously adapted for night hunting. With their help, the snake searches for small warm-blooded animals and birds. Not smell, but body heat betrays the victim! After all, snakes have poor eyesight and smell, and completely unimportant hearing. A new, very special feeling came to their aid - thermal location.

In the experiments of D. Noble and A. Schmidt, an indicator that the snake found a warm light bulb was its throw. But after all, the snake, of course, even before it rushed to the attack, already felt the approach of a warm object. This means that it is necessary to find some other, more accurate signs by which one could judge the subtlety of the thermolocation sense of the snake.

American physiologists T. Bullock and R. Cowles conducted more thorough research in 1952. As a signal announcing that the object was detected by the snake's thermolocator, they chose not the reaction of the snake's head, but a change in biocurrents in the nerve serving the facial fossa.

It is known that all processes of excitation in the body of animals (and humans) are accompanied by reactions arising in muscles and nerves. electric currents. Their voltage is small - usually hundredths of a volt. These are the so-called "biocurrents of excitation". Biocurrents are easy to detect with the help of electrical measuring instruments.

T. Bullock and R. Kauls anesthetized snakes by introducing a certain dose of curare poison. They cleaned one of the nerves branching in the membrane of the facial fossa from muscles and other tissues, brought it out and clamped it between the contacts of a device that measures biocurrents. Then the facial pits were subjected to various influences: they were illuminated with light (without infrared rays), strong-smelling substances were brought close, irritated strong sound, vibration, tweaks. The nerve did not react: there were no biocurrents.

But it was worth bringing a heated object closer to the snake's head, even just human hand(at a distance of 30 centimeters), as excitement arose in the nerve - the device recorded biocurrents.

Illuminated the pits with infrared rays - the nerve was even more excited. The weakest reaction of the nerve was found when it was irradiated with infrared rays with a wavelength of about 0.001 millimeters. The wavelength increased - the nerve was more excited. The greatest reaction was caused by the longest-wavelength infrared rays (0.01 - 0.015 millimeters), that is, those rays that carry the maximum thermal energy emitted by the body of warm-blooded animals.

It also turned out that rattlesnake thermolocators detect not only warmer, but even colder objects than the surrounding air. It is only important that the temperature of this object be at least a few tenths of a degree higher or lower than the surrounding air.

The funnel-shaped openings of the facial pits are directed obliquely forward. Therefore, the range of the thermolocator lies in front of the snake's head. Up from the horizontal, it occupies a sector of 45, and down - at 35 degrees. To the right and to the left of the longitudinal axis of the body of the snake, the field of action of the thermolocator is limited to an angle of 10 degrees.

physical principle, on which the thermolocator device of snakes is based, is completely different from that of squids.

Most likely, in the thermoscopic eyes of squids, the perception of a heat-radiating object is achieved through photochemical reactions. Here, probably, processes of the same type take place as on the retina of an ordinary eye or on a photographic plate at the moment of exposure. The energy absorbed by the organ leads to the recombination of light-sensitive (in squids - heat-sensitive) molecules, which act on the nerve, causing the representation of the observed object in the brain.

Snake thermolocators act differently - according to the principle of a kind of thermoelement. The thinnest membrane separating the two chambers of the facial fossa is exposed to two different temperatures from different sides. The inner chamber communicates with the external environment through a narrow channel, the inlet of which opens in opposite side from the working field of the locator.

Therefore, the ambient temperature is maintained in the inner chamber, (Neutral level indicator!) The outer chamber, with a wide opening - a heat trap, is directed towards the object under study. The heat rays that it emits heat the front wall of the membrane. According to the temperature difference on the inner and outer surfaces of the membrane, simultaneously perceived by the nerves in the brain, there is a feeling of a radiating thermal energy subject.

In addition to pit snakes, thermolocation organs have been found in pythons and boas (in the form of small pits on the lips). The little pits above the nostrils in the African, Persian, and some other species of viper seem to serve the same purpose.

Snakes are one of the most mysterious inhabitants of our planet. Primitive hunters, when meeting with any snake, hurried to flee from it, knowing that just one bite could doom them to death. Fear helped avoid bites, but prevented learning more about these. mysterious creatures. And where there was not enough exact knowledge, the gaps were filled with fantasies and conjectures, which became more and more sophisticated over the centuries. And, despite the fact that many of these reptiles have already been studied quite well, the old, passed down from generation to generation, rumors and legends about snakes still own the minds of people. In order to somehow break this vicious circle, we have collected the 10 most common myths about snakes and refuted them.

snakes drink milk

This myth became known to many of us thanks to the work of Conan Doyle's "Colored Ribbon". In fact, trying to drink milk to a snake can end fatal: they do not absorb lactose in principle.

Attacking, snakes sting

For unknown reasons, many people believe that snakes sting with their sharp, forked tongues. Snakes bite with their teeth, like all other animals. Language serves them for completely different purposes.

Snakes before the throw, threatening, stick out their tongue

As already mentioned, the snake's tongue is not designed to attack. The fact is that snakes do not have a nose, and all the necessary receptors are located on their tongue. Therefore, in order to better smell the prey and determine its location, snakes have to stick out their tongue.

Most snakes are venomous

Of the two and a half thousand species of snakes known to serpentologists, only 400 have poisonous teeth. Of these, only 9 are found in Europe. Most venomous snakes in South America- 72 species. The rest were almost evenly distributed across Australia, Central Africa, South-East Asia, Central and North America.

You can "secure" a snake by pulling out its teeth

For a while, this might actually work. But the teeth will grow back, and the snake during their growth, not being able to express the poison, can become seriously ill. And by the way, it is impossible to train a snake - for them, any person is nothing more than just a warm tree.

Snakes always attack when they see people.

As statistics show, most often snakes bite people in self-defense. If a snake hisses and makes threatening movements at the sight of you, it means that she just wants to be left alone. As soon as you step back a little, the snake immediately disappears from view, in a hurry to save its life.

Snakes can be fed meat

Most snakes feed on rodents, there are species that eat frogs and fish, and even insectivorous reptiles. And king cobras, for example, prefer only snakes of other species to eat. So what exactly to feed the snake depends only on the snake itself.

Snakes are cold to the touch

Snakes are typical representatives of cold-blooded animals. And so the body temperature of the snake will be the same as the temperature external environment. Therefore, not being able to support optimum temperature bodies (a little above 30 ° C), snakes love to bask in the sun so much.

snakes covered in slime

Another bike that has nothing to do with snakes. The skin of these reptiles contains practically no glands and is covered with dense smooth scales. It is from this pleasant to the touch snake skin that shoes, handbags and even clothes are made.

Snakes wrap around the branches and trunks of trees

Quite often you can see the image of the snake-tempter, wrapping around the trunk of the tree of knowledge. However, this has nothing to do with their actual behavior. Snakes climb onto tree branches and lie on them, but they don’t need to wrap their body around them.

reptile eyes testify to their way of life. At different types we observe a peculiar structure of the organs of vision. To protect their eyes, some "cry", others have eyelids, and still others "wear glasses".
reptile vision , like the variety of species, is very different. The way the eyes are located on the reptile's head largely determines how much the animal sees. When the eyes are set on both sides of the head, the visual fields of the eyes do not overlap. Such animals see well everything that happens on both sides of them, but their spatial vision is very limited (they cannot see the same object with both eyes). When the eyes of a reptile are set in front of the head, the animal can see the same object with both eyes. This position of the eyes helps reptiles more accurately determine the location of prey and the distance to it. IN land turtles and many lizards have eyes set on both sides of the head, so they can see everything that surrounds them well. The Cayman tortoise has excellent spatial vision because its eyes are set in front of its head. The eyes of chameleons, like cannons in defense towers, can rotate independently 180° horizontally and 90° vertically - they see behind them.

How do snakes show a source of heat?.
The most important sense organ of the snake is the tongue in combination with Jacobson's organ. However, reptiles have other adaptations necessary for successful hunting. In order to identify prey, snakes need more than just eyes. Some snakes can perceive heat radiated from the animal's body.
The pit-headed snakes, which include the real grimuchnik, got their name due to the fact that they have a paired sense organ, in the form of facial pits located between the nostrils and the eye. With the help of this organ, snakes can feel warm-blooded animals by the temperature difference between its body and the external environment with an accuracy of 0.2 ° C. The size of this organ is only a few millimeters, but it can capture infrared rays emitted by potential prey and transmit the information received through nerve endings in the brain. The brain perceives this information, analyzes it, so the snake has a clear idea of ​​what kind of prey it met on the way and where exactly it is located. Different kinds reptiles are very differently seen and perceived the world. The field of view, its expressiveness and ability to distinguish colors depend on how the animal's eyes are set, on the shape of the pupils, as well as on the number and type of light-sensitive cells. In reptiles, vision is also associated with a way of life.
color vision
Many of the lizards can perfectly distinguish colors, which for them is an important means of communication. Some of them on a black background recognize scarlet poisonous insects. In the retina of the eyes of diurnal lizards there are special elements of color vision - flasks. Giant tortoises are color-aware, some of them responding particularly well to red light. They are even thought to be able to see infrared light, which the human eye cannot see. Crocodiles and snakes are color blind.
American night lizards react not only to shape, but also to color. However, their retina still contains more rods than cones.
reptile vision
The class of reptiles, or reptiles, includes crocodiles, alligators, turtles, snakes, geckos, and lizards such as the tuatara. The reptile needs to get accurate information about the size and color of its potential prey. In addition, the reptile must detect and quickly react when other animals approach and determine who it is - a potential partner, a young animal of the same species, or an enemy that can attack it. Reptiles that live underground or in water have rather small eyes. Those of them that live on earth are more dependent on visual acuity. The eyes of these animals are arranged in the same way as the eyes of a person. Their most part is the eyeball with the optic nerve. In front of it is the cornea, which transmits light. On the cornea - the iris. In its center is the pupil, which narrows or expands, letting a certain amount of light into the retina. The lens is located under the pupil, through which the rays enter the light-sensitive back wall of the eyeball - the retina. The retina is made up of layers of light and color sensitive cells connected by optic nerves to the brain, where all signals are sent and where an image of an object is created.
Eye protection
In some species of reptiles, eyelids are used to protect the eyes, as in mammals. However, reptilian eyelids differ from mammalian eyelids in that the lower eyelid is larger and more mobile than the upper eyelid.
The snake's gaze seems to be glassy, ​​since its eyes are covered with a transparent film, which is formed by the fused upper and lower eyelids. This protective coating is a kind of "glasses". During molting, this film comes off with the skin. "Points" are worn by lizards, but only a few. Geckos do not have eyelids. To cleanse the eyes, they use the tongue, sticking it out of the mouth and licking the eye membrane. Other reptiles have a "parietal eye". This is a bright spot on the head of a reptile; like an ordinary eye, it can perceive certain light stimuli and transmit signals to the brain. Some reptiles use their lacrimal glands to protect their eyes from pollution. When sand or other debris gets into the eyes of such reptiles, the lacrimal glands secrete a large number of liquid that cleans the eyes of the animal, while it seems as if the reptile is "crying". Soup turtles use this method.
The structure of the pupil

The pupils of reptiles testify to their way of life. Some of them, for example, crocodiles, pythons, geckos, hatteria, snakes, lead a nocturnal or twilight lifestyle, and take sunbaths during the day. They have vertical pupils that dilate in the dark and constrict in the light. In geckos, pinholes are visible on constricted pupils, each of which focuses an independent image onto the retina. Together they create the necessary sharpness, and the animal sees a clear image.

It is interesting to read about penguins on the website kvn201.com.ua.