How do snakes crawl? Snakes are very agile and dexterous animals. They can crawl, and quite quickly, not only on flat terrain, but also on mountains, through trees, some of them can swim, and they do all this without having arms or legs. Experts say that snakes

Where does a snake have venom? Currently, there are about 2,400 different species of snakes around the globe. Of these, only 412 are poisonous. But not all of these snakes are dangerous to humans. Some poisonous snakes have such weak venom that it can only kill a lizard or a frog. But

13. Magical snakes In the vast majority of cultures, snakes were considered a symbol of the Goddess and/or kundalini energy. In addition, they were believed to be immortal, since they shed their skin, and it seemed that they had a new life. The Greeks called the skin shed by snakes geras,

Snakes of Sheba Ancient Arabic legends tell of an unusual type of snake called the snake of Sheba. These royal purple snakes were believed to live in or near the Temple of the Moon located in Marib, the capital of the state of Sheba. Instead of crawling on the ground,

Internal structure of a snake

Since the snake’s body is long and narrow, all organs located inside the body must have corresponding sizes, therefore all the internal organs of the snake are very long. Their placement is also peculiar. In many snakes they are located asymmetrically, and in the most highly organized snakes, paired organs have become unpaired. Worm-like snakes, for example, have two lungs, but the right one is always larger than the left. In more highly organized snakes, the left lung is absent, the right is well developed, and in snakes such as vipers, as compensation for the atrophied left lung, the back of the trachea expanded and formed the so-called tracheal lung. The back of the preserved right lung has a very thin wall, the tissue of which can stretch well. This helps the snake swell when it inhales, visually increasing its body size to scare off enemies, and when it exhales, it makes a loud warning hiss.

The esophagus of snakes is quite long and is a tube with very powerful muscular walls that can flatten and push food into the stomach. The stomach of snakes also acquired an elongated shape, but the intestines became shorter. Some snakes have slightly wider bodies and stomachs than most other species. This allows them to feed on larger prey.

The kidneys of snakes are paired, very long and narrow. The right kidney is moved closer to the head, and the left one - towards the tail. There is no bladder, and the ureter opens directly into the cloaca.

The reproductive organs are paired, in females they are represented by a pair of ovaries, and in males they are represented by elongated testes and a kind of copulatory organ. This organ looks like two sacs equipped with small spines. The sacs are usually located under the skin behind the anus and can be detected by probing with a thin wire. During mating, the male turns the copulatory organ outward and inserts it into the female’s cloaca.

Features of the blood supply of snakes
R. Seymour (University of Adelaide, Australia) and H. Lillywhite (University of Kansas, USA) studied the blood supply systems of nine species of snakes. Significant differences in these systems have been established depending on the lifestyle characteristic of a given species. Thus, the blood pressure of snakes living in trees reaches 74 millimeters. Herpetologists know that such snakes remain in an upright position for a long time, in which the blood supply to the brain naturally requires significant effort from the body. In water snakes, which remain in a horizontal position for a long time, the blood pressure does not exceed 22 millimeters of mercury. A certain pattern was also established in the location of the heart. In all land species of snakes it is located closer to the head, and in water snakes it is almost exactly in the middle of the body.

Glands
In addition to the glands that make up the snake's venomous apparatus, there are also skin glands on the snake's body. Some snakes use the poisonous or foul-smelling secretions from these glands to ward off predators. For example, in a beautiful Far Eastern snake - the tiger snake - similar glands are located on the back in the front part of the body. They secrete a yellowish secretion that irritates the mucous membranes. If a dog grabs such a snake, he will immediately throw it away and begin to shake his head, trying to get rid of the burning sensation in his mouth. In the skin of snakes there are areas of the so-called glandular epidermis, which secrete fatty substances that lubricate the scales and thereby facilitate their gliding when crawling. In addition, these substances have a specific smell (which, probably, was felt by anyone who held snakes in their hands). Thanks to this, the crawling snake leaves an invisible scent trail, which helps individuals of the same species find each other.

Nervous system
The brain of snakes, located in a durable bone capsule, is relatively small, so higher nervous activity in snakes is poorly developed. The spinal cord, on the contrary, is very large and well developed, which ensures excellent coordination of the snake’s movements, lightning-fast reactions, and precision muscle control. For example, a yellow-bellied snake, which is given several rodents in its terrarium, is capable of taking three or four mice at a time. He grabs one rodent with his mouth, strangles the second with a ring in the upper part of the body, and presses the third and fourth to the walls of the terrarium, bending the middle and rear parts of the body.

A snake is an animal of the chordate type, class Reptiles, order Squamate, suborder snakes (Serpentes). Like all reptiles, they are cold-blooded animals, so their existence depends on the ambient temperature.

Snake - description, characteristics, structure. What does a snake look like?

The body of the snake has an elongated shape and can reach a length of 10 centimeters to 9 meters, and the weight of the snake ranges from 10 grams to more than 100 kilograms. Males are smaller than females, but have a longer tail. The body shape of these reptiles varies: it can be short and thick, long and thin, and sea snakes have a flattened body that resembles a ribbon. Therefore, the internal organs of these scaly animals also have an elongated structure.

The internal organs are supported by more than 300 pairs of ribs, movably connected to the skeleton.

The snake's triangular head has jaws with elastic ligaments, which makes it possible to swallow large food.

Many snakes are venomous and use venom as a means of hunting and self-defense. Since snakes are deaf, to navigate in space, in addition to vision, they use the ability to capture vibration waves and thermal radiation.

The main information sensor is the forked tongue of the snake, which allows it to “collect information” about the environment using special receptors inside the palate. Snake eyelids are fused transparent films, scales covering the eyes, therefore snakes don't blink and even sleep with their eyes open.

The skin of snakes is covered with scales, the number and shape of which depends on the type of reptile. Once every six months, the snake sheds its old skin - this process is called molting.

By the way, the color of the snake can be either monochromatic in species living in the temperate zone, or variegated in representatives of the tropics. The pattern can be longitudinal, transversely circular or spotted.

Types of snakes, names and photographs

Today, scientists know more than 3,460 species of snakes living on the planet, among which the most famous are adders, sea snakes (not dangerous to humans), pit snakes, pseudopods, which have both lungs, as well as rudimentary remains of the pelvic bones and hind limbs.

Let's look at several representatives of the snake suborder:

• King cobra (hamadryad) ( Ophiophagus hannah)
  

The most gigantic poisonous snake on earth. Some representatives grow up to 5.5 m, although the average size of adults usually does not exceed 3-4 m. King cobra venom is a lethal neurotoxin, causing death in 15 minutes. The scientific name of the king cobra literally means “snake eater”, because it is the only species whose representatives feed on snakes of their own kind. Females have an exceptional maternal instinct, constantly guarding the clutch of eggs and completely going without food for up to 3 months. The king cobra lives in the tropical forests of India, the Philippines and the islands of Indonesia. Life expectancy is more than 30 years.

• Black Mamba ( Dendroaspis polylepis)

The African venomous snake, growing up to 3 m, is one of the fastest snakes, capable of moving at a speed of 11 km/h. The highly toxic snake venom causes death in a matter of minutes, although the black mamba is not aggressive and attacks humans only in self-defense. Representatives of the black mamba species received their name due to the black coloration of the oral cavity. The snake's skin is usually olive, green or brown in color with a metallic sheen. It eats small rodents, birds and bats.

• Fierce snake (desert taipan) ( Oxyuranus microlepidotus)

The most poisonous of land snakes, the venom of which is 180 times stronger than that of a cobra. This species of snake is common in the deserts and dry plains of Australia. Representatives of the species reach a length of 2.5 m. Skin color changes depending on the season: in extreme heat it is straw-colored, when it gets colder it becomes dark brown.

• Gaboon viper (cassava) ( Bitis gabonica)

The poisonous snake that lives in the African savannas is one of the largest and thickest vipers, up to 2 m long and with a body girth of almost 0.5 m. All individuals belonging to this species have a characteristic, triangular head with small horns located between the nostrils . The Gaboon viper has a calm character, rarely attacking people. It belongs to the type of viviparous snakes, breeds once every 2-3 years, bringing from 24 to 60 offspring.

• Anaconda ( Eunectes murinus)

The giant (ordinary, green) belongs to the subfamily of boas; in former times the snake was called a water boa. The massive body, 5 to 11 m long, can weigh over 100 kg. The non-venomous reptile is found in low-flow rivers, lakes and creeks of the tropical part of South America, from Venezuela to the island of Trinidad. It feeds on iguanas, caimans, waterfowl and fish.

• Python ( Pythonidae)

A representative of the family of non-venomous snakes, it is distinguished by its gigantic size, ranging from 1 to 7.5 m in length, with females being much larger and more powerful than males. The range extends throughout the eastern hemisphere: tropical forests, swamps and savannas of the African continent, Australia and Asia. The diet of pythons consists of small and medium-sized mammals. Adults swallow leopards, jackals and porcupines whole, and then digest them for a long time. Female pythons lay eggs and incubate the clutch, by contracting muscles, increasing the temperature in the nest by 15 -17 degrees.

• African egg snakes (egg eaters) ( Dasypeltis scabra)

Representatives of the snake family that feed exclusively on bird eggs. They live in savannas and woodlands of the equatorial part of the African continent. Individuals of both sexes grow no more than 1 meter in length. The movable bones of the snake's skull make it possible to open its mouth wide and swallow very large eggs. In this case, the elongated cervical vertebrae pass through the esophagus and, like a can opener, rip open the eggshell, after which the contents flow into the stomach, and the shell is coughed up.

• Radiant snake ( Xenopeltis unicolor)

Non-venomous snakes, the length of which in rare cases reaches 1 m. The reptile received its name for the rainbow tint of its scales, which are dark brown in color. Burrowing snakes live in the loose soils of forests, cultivated fields and gardens in Indonesia, Borneo, the Philippines, Laos, Thailand, Vietnam and China. Small rodents and lizards are used as food items.

• Worm-like blind snake ( Typhlops vermicularis)

Small snakes, up to 38 cm long, resemble earthworms in appearance. Absolutely harmless representatives can be found under stones, melons and watermelons, as well as in thickets of bushes and on dry rocky slopes. They feed on beetles, caterpillars, and their larvae. The distribution area extends from the Balkan Peninsula to the Caucasus, Central Asia and Afghanistan. Russian representatives of this species of snake live in Dagestan.

Where do snakes live?

The distribution range of snakes does not include only Antarctica, New Zealand and the islands of Ireland. Many of them live in tropical latitudes. In nature, snakes live in forests, steppes, swamps, hot deserts and even in the ocean. Reptiles lead an active lifestyle both during the day and at night. Species living in temperate latitudes hibernate in winter.

The number of vertebrae in snakes of various species depends on their size and varies from 141 to 435. The last vertebrae, ranging from 2 to 10, are caudal; the trunk vertebrae bearing short ribs are not divided into sections.

Some species of snakes lack a chest, which allows them to absorb large amounts of food and also allows them to get into the most inaccessible places: crevices and cracks.

Reptiles move by relying on ribs and convex plates located on the belly. Several methods of movement of snakes are known: lateral wavy, rectilinear, spiral, lateral.

With a lateral wave-like movement, the snake describes curves with its body that resemble the shape of the letter S. With a rectilinear movement, resting on small plates on the belly, the animal pushes part of its body forward and then leans back.

The spiral movement is used when climbing trees: the snake wraps its tail around a tree trunk, throws up the front part of its body, clings to a branch, and then pulls up its lower body.

The lateral move is an alternating movement: pushing the front part of the body to the side and pulling up the back. An important role in describing snakes is played by the features of the scaly cover, the number, shape, size and location of the head shields, grouped in an order characteristic of each individual species. It is also necessary to pay attention to the horny scales covering the body of snakes. As a rule, they are diamond-shaped, smooth to the touch, with a longitudinal keel, and arranged in a tiled manner.

Between the scales there are areas of skin collected in small folds. When the snake swallows large prey, the longitudinal rows of horny scales expand, the folds of the skin straighten out, and the body greatly increases in diameter.

Of no small importance when describing the species is the number of scales around the body, which are counted around the middle of the body at an angle. This does not take into account the number of abdominal scutes, starting from the first, elongated, located on the throat, and ending with the anal, lying in front of the cloacal opening. The abdominal scutes are connected by soft leathery folds, which straighten when swallowing food. The abdominal scutes diverge in the longitudinal direction.

The top layer of skin of healthy snakes peels off 2-4 times a year. Shedding starts from the front of the head. Trying to free themselves from old skin, snakes begin to actively move, rubbing their heads on stones and soil. As a result, the old skin completely falls off the reptile’s body. Sick animals shed more often, and their skin peels off in pieces.

The skull of snakes is designed in such a way that when capturing prey, their mouth stretches wide, allowing them to swallow alive an animal that is often thicker than the body of the reptile itself. The front part of the skull, to which the lower jaw is attached by elastic ligaments, is equipped with movable, interconnected bones. The brain is enclosed in a bone capsule.

The formation of well-developed, thin, sharp teeth, directed towards the pharynx and serving not for chewing, but for holding prey and pushing it into the esophagus, occurs on the upper and lower jaws, and in some snakes - on the palatine, pterygoid, premaxillary bones. Behind a pair of active teeth there are usually spare ones, which grow quickly if the working pair breaks.

The tongue is the most important sensory organ of snakes. With the forked tip of its tongue, the snake touches nearby objects, receives information about substances contained in the air, follows the trail of prey, looks for a partner, and finds water.

The eyes of snakes lack separate eyelids and are covered with a motionless transparent leathery membrane, so they appear to be constantly open. The result of this eye structure is a decrease in visual acuity. It is worth noting that during molting, which affects the cornea of ​​the eye, the reptile completely loses the ability to see, but after a few days, vision is restored, since the leathery film that has faded along with the cuticle is replaced by a new transparent shell. Snakes that lead a diurnal lifestyle have a round pupil; in twilight and nocturnal snakes it is elongated into a vertical slit and resembles a cat’s.

Representatives of this suborder of reptiles have a well-developed sense of smell. The nostrils, located on the side or top of the head, are equipped with closing valves that protect against the ingress of water when diving and sand when crawling. The nervous system of snakes is represented by a small brain and a long spinal cord, which determines precise coordination of body movements, sensitivity to ground vibrations, which compensates for the lack of hearing.

The internal organs of snakes (some of them are unpaired) are, as a rule, elongated and located asymmetrically. Thus, in some species both lungs are developed, but the right one is larger than the left; in representatives of other species, the left lung may be absent, which in no way affects the life activity of snakes. The digestive system, represented by the rectum, is short, the stomach and kidneys are elongated, and there is no bladder. The testes of males are elongated, the genital organ looks like paired sacs located under the skin behind the anus. The body length of snakes is measured from the head to the anterior edge of the cloaca opening, the tail length is measured from the anterior edge of the cloaca to the tip of the tail.

We invite you to learn some amazing facts from the life of reptiles.

They're everywhere (almost)

Our planet is home to more than 2,900 species of snakes, found everywhere from the Arctic Circle in Scandinavia to southern Australia. They can be found on every continent except Antarctica (Ireland, Greenland, Iceland and New Zealand also had no snakes), and even deep underwater and high in the mountains.

Snakes have a special internal structure

Have you ever wondered how the internal organs of a snake work? Well, maybe not, but in fact the structure of these creatures is amazing, since they do not have a body as such to house the main systems. Snakes' paired organs, such as kidneys, are located front and back rather than left and right, and they only have one functioning lung.

Schematic representation of the internal organs of a snake: 1 - esophagus, 2 - trachea, 3 - tracheal lung, 4 - rudimentary left lung, 5 - right lung, 6 - heart and thymus, 7 - liver, 8 - stomach, 9 - air (swimming) ) sac, 10 - gallbladder, 11 - pancreas, 12 - spleen, 13 - intestines, 14 - testes, 15 - kidneys.

The location of the heart can change, it moves due to the absence of a diaphragm, so that large pieces of food do not compress it when swallowed and move along the esophagus.

They sniff with their tongue

We often associate the word “snake” with the hissing and fluttering of a forked tongue from an open mouth. Why do they do this? The fact is that snakes smell using their tongue, collecting airborne particles and then transferring them to the olfactory organs in the mouth. The two parts of the tongue give the reptile something of a sense of direction as to where smells or tastes are coming from. Through these rapid movements, snakes are able to sense chemicals in the air, soil and water, and use them to detect the presence of nearby prey or predators.

Snakes are sensitive

Sensitive not in the sense of touching soap operas, but differently: snakes have a subtle sense of vibration. The slippery part of the abdomen can detect even the slightest vibrations in the air and on the ground, which gives the reptile the ability to sense the approach of other animals.

In addition, some rattlesnakes, pythons and boas also have infrared receptors in the depressions on their heads that allow them to sense the heat emitted by any warm-blooded animal nearby.

They eat what suits them

Snakes exclusively consume a variety of animals, including small lizards, other snakes, small mammals, birds, eggs, fish, snails or insects and up to large mammals such as jaguars and deer.

Since snakes eat their prey in one large gulp, the size of the reptile determines the size of the animal it consumes. For example, a young python may start out with lizards or mice, moving on to small deer and antelope as they age and increase in body size.

Their sizes vary from 10 cm to 10 m

Most snakes are relatively small, about a meter long. The extinct snake Titanoboa cerrejonensis was 12-15m long, but today's longest reptile is the reticulated python at around 10m. At the other end of that line is the 10cm tiny Leptotyphlops carlae.

The weight of the heaviest snake is 250 kg

The South American anaconda grows up to 9 m in length and reaches a weight of 250 kg. On land, these reptiles are rather clumsy, and therefore live near shallow rivers and swamps, spending most of their time in the water, where they can move faster. The anaconda's eyes and nostrils are located on the top of its head, and these snakes stalk prey like alligators, leaving their bodies below the surface of the water.

And what animals does the heaviest snake in the world hunt to maintain its impressive mass? These are wild boars, deer, birds, turtles, capybaras, caimans and even jaguars, which the snake strangles, squeezing with its powerful body. Its jaws are connected by flexible ligaments, allowing them to swallow a whole meal, which sometimes lasts for weeks or even months.

Some snakes can fly!

Are you fascinated by the sight of a reptile slithering through the grass? What can you say about a snake rushing through the air? Yes, there are five species of venomous tree-dwelling snakes that can fly. They can be seen on the island of Sri Lanka and in Southeast Asia, and are technically more gliders than fliers, as they use the speed of free fall from a tree and contraction of body muscles to catch rising air currents.