Muscular system reptiles are represented by chewing, cervical muscles, muscles abdominals, as well as flexor and extensor muscles. There are intercostal muscles characteristic of higher vertebrates that play important role during the act of breathing. Subcutaneous muscles allow you to change the position of the horny scales.

Muscles of the head.

Due to the fact that snakes do not chew their prey, but swallow it whole, their chewing muscles do not achieve strong development and serve to open and close their jaws and hold prey with the help of numerous small teeth. The facial muscles are underdeveloped, so the lips and tip of the nose of snakes are practically motionless and have a strong connective tissue base.

Muscles of the spinal column.

This muscle group is highly developed and well differentiated. Snakes have the following groups of multisegment muscles:

Longissimus muscles of the trunk and tail (m. longissimus trunci et coccygey) - These muscles provide extension of the spinal column and lateral movements torso.

Interspinous muscles (m. interspinales) - They contribute to the extension of the spinal column.

Short intertransverse muscles (m. intertransversarii) - provide lateral movements of the body of snakes.

Rib levators m. levatori costarum) - These muscles are most developed in cobras in cervical spine and provide expansion of the neck with the formation of a “hood”.

snake suborder poisonous skeleton

Rib retractors m. retractors costarum) - begin at the proximal end of the rib, ending at the arch of the underlying vertebra.

Descenders of the ribs (m. depressores costarum) - begin on the ventral surface of the proximal end of the rib, ending on the ventral surface of the vertebral body.

Intercostal muscles (m. intercostals) - located between the ribs, highly developed.

The flexors of the spinal column (m. flexores) - highly developed, especially in boas and pythons, are located on the ventral surface of the vertebral bodies, spreading through several segments - these are the long muscles of the trunk and tail.

The strong development and elasticity of the described muscle groups ensures a serpentine type of movement, that is, movement using bends of the body and ribs that are not closed ventrally. In other words, snakes, writhing, “walk on their ribs.” When the snake makes a bend, the longissimus and intertransverse muscles on the side of the bend are tense, and on the side opposite the bend they are relaxed. During a forward lunge, these muscles are in the opposite functional state.

Movement

When the snake moves, each abdominal shield, with the help of the corresponding muscles, takes a position at right angles to the skin. With the shield in this position, the animal rests on the ground. One movement of the muscles - the shield is pressed to the skin, and the next one takes its place. During the movement of the snake, the shield behind the shield becomes an instant point of support and repulsion, and only thanks to them is forward movement possible. The scutes serve the snake as if it were a hundred tiny legs.

The movements of the vertebrae, ribs, muscles and scutes are strictly coordinated; they occur in the horizontal plane. The raised head of the snake is lowered to the ground, then the loop of the front third of the body is pulled up; then the snake again moves its head forward to rest it on the ground again, make another forward movement and pull the whole body along with it. Until the snake gets a foothold, it is unable to move. The snake will not be able to move on the smooth surface of the glass, since the transverse shields will only slide along it.

If you follow a snake while it is X-rayed, you can see how complex the coordinated movements of its skeleton are. The spine easily bends in any direction and thanks to this, the snake’s body can either curl up into a ring, or rise by almost a third of its length above the ground, or rush forward with incredible speed.

Methods of movement of a snake

In fact, snakes can move on land in four main ways. If one method is not suitable, then they use another. Sometimes, especially on very flat surface, they have to try all four methods. The crawling of snakes can be quite rapid, and some of them are even capable of chasing their prey. However, even the fastest snakes rarely reach speeds exceeding 8 km/h. The crawling speed record is 16-19 km/h and belongs to the black mamba.

1. Accordion movement.

First, the snake gathers its body into folds. Then, holding the tip of the tail in place, he pushes the front of the body forward. And finally tightens the back of the body.

2. Movement by caterpillar.

The snake can move in a straight line. She uses this movement when she needs to overcome some bottleneck. At the same time, the snake moves large scales located on its belly. One by one, the scales sink into the ground like small shovels. As soon as the scales sink into the ground, the muscles move them towards the tail. One by one, the scales are repelled from the ground, and due to this, the snake moves.

3. Twisting movement.

Designed to move on hard ground. To move forward, the snake bends its body to the side, resting against stones, roots, sticks or other hard objects. During this movement, snakes alternately contract the muscles on their sides, so that their body bends in an S-shape: the snake wriggles and crawls.

Wave-like bending of the body is the most common way of snakes crawling.

4. Coiling or lateral movement is a method of movement that is used only by some species of snakes living in the desert. Using this method, they can move quickly through loose sand. In this case, the snake’s head goes sideways and forward, and then the body is pulled up. Snakes begin to almost walk, if one can say so about completely legless creatures: leaning on the back part of the body, they carry the front part forward, then vice versa.

5. Digging move.

These include, for example, blind snakes.

Many species of blind snakes have tiny eyes that can distinguish light from dark; some species have no eyes at all. A strong skull and large scutes on the front of the head help blind snakes build tunnels in the thickness of loose soil.

Snakes often take refuge underground from heat or cold. Others find the burrows of small animals and, climbing into them, eat their owners. For some desert snakes sand serves as an excellent shelter. With only their head above its surface, they patiently wait for prey.

6. Woody appearance.

Many snakes are good at climbing branches of trees and bushes. But some species of snakes spend their entire lives in treetops. Such snakes are called arboreal snakes. When hunting for lizards, the Mexican sharp-headed snake often throws its body from branch to branch. In preparation for “flight,” the snake flattens its body, spreading its ribs greatly. This allows her to glide smoothly in the air.

There is no doubt that the imagination of nature significantly exceeds that of man: amazing shapes, bright colors, all possible sizes of living and extinct representatives of flora and fauna often simply do not fit into the framework of our perception. But, unlike the characters in science fiction books and films, real organisms each of these expressive features is necessary to perform a particular function. This especially affects the method of movement.

Smooth fish scales covered with a thin layer of mucus; durable yet lightweight bird feathers; thin leathery membranes of flying lizards; cat claws; distant thumb in primates; numerous “finds” for upright walking, which people are so proud of; arthropods have six or even more pairs of legs. But each of these limbs needs to be controlled, and even balanced with the rest of the body, so that you don’t have to lift it again.

In this regard, snakes, worms and legless amphibians have done right choice- if you are already on the surface, then, in fact, you have nowhere to fall. But the mechanics of their movement turned out to be much more complicated than it seemed. David Hu of New York University and his colleagues

proved that characteristic crawling is ensured uneven distribution frictional forces on the surface of the body in contact with the ground and constant redistribution weight.

This is how they fundamentally differ from their “brothers” in misfortune - worms and legless amphibians. The latter synthesize a copious amount of mucus; the worms push themselves forward, clinging to small hairs. But in the case of snakes, until recently, one could only rely on hypotheses.

According to one of them, the friction force in the longitudinal direction was significantly less than that in the transverse direction. If we add the ability to twist, the loops will provide the necessary stability, while moving forward will continue. A demonstration of this approach are wheeled robotic snakes, whose body moves easily forward and does not move sideways at all. However, they also need support points from which to build. In the case of sand or bare stone, this approach will not work.

Authors publications in Proceedings of the National Academy of Sciences have significantly expanded the existing understanding of the movement of these reptiles. Their wards were 10 young milk snakes (Campbell's king snake or Lampropeltis triangulum campbelli). These snakes that live in North America, are known for being very similar in appearance to poisonous coral adders, although they themselves are much less dangerous.

To begin with, the experimenters euthanized the reptiles and measured the friction force in all directions.

As expected, when moving to the side it turned out to be almost twice as large, and backward - one and a half times, than when moving forward.

But this is only if the surface is rough. If something super-smooth acted as a substrate, then the friction force in all directions tended to zero. However, they did not expect a miracle from snakes - it would be strange to believe that scales cling differently to something that, in principle, is impossible to cling to.

The resulting model also explains the ability of snakes to move on an inclined surface and gives calculated speeds that are almost approaching real ones.

Dynamic load distribution during lateral bending. Top photo— A snake crawling across a mirror. This picture shows the "wave" used to redistribute the weight. Although this photo was taken for demonstration purposes (the surface is smooth, so the reptile hardly moves), the same phenomenon was observed when moving on rough surfaces. Below is the calculated driving force on models with uniform (middle row) and uneven (bottom row) weight distribution. The red dot marks the center of mass, the black dots indicate the places highest pressure to the surface //David L.Hu et al., PNAS

Scientists explain the missing “kilometers per hour” by a kind of wave that the snake sends through its body. It was possible to register it by video recording movement on a mirror surface. In this case, reptiles do not completely tear off their body, but only reduce the load on certain areas, constantly moving the center of mass.

The authors even expect to find their discovery practical use— such robots in some cases are significantly superior to wheeled and even “six-fingered” robots. Wheels will be absolutely useless if the height of the obstacle is more than half the diameter of the wheel, and the limbs require much more space for maneuver than a thin flexible body. So, when clearing rubble or in reconnaissance, such robotic snakes can be of great use. All that remains is to learn how to make snake-like scales.

American researchers have discovered the mechanism of movement of snakes. This was reported by Science NOW, and the researchers appeared in the journal Proceedings of the National Academy of Sciences.

At the first stage of the study, scientists studied the properties of the skin on the belly 10 king snakes Campbell ( Lampropeltis triangulum campbelli) - small reptiles about 35 centimeters long.

After tranquilizing them, the researchers moved the snakes around different surfaces. As a result, they were able to establish that when moving on a smooth surface, the friction force is approximately the same in all directions. If the surface is rough, then it is twice as difficult to move the snake sideways as it is forward. In addition, shifting backward is one and a half times more difficult than shifting forward.

If you try to tilt slippery surface, then the snake can overcome a maximum seven-degree inclination:

The scientists then studied videos of the snakes moving. Previously, scientists knew that while crawling, a snake sends a kind of “wave” through its body. The researchers were able to establish that during the passage of the “wave,” the reptile lifts some parts of the body, reducing the friction force on the surface in unnecessary places and increasing it where the body is repelled.

By putting the collected information into a computer, scientists received a model of a snake that moved as fast as its living counterparts:

According to the researchers, the new results can be used to create a new generation of robots that will be able to move like snakes. Such mechanisms can be useful, for example, in searching for and rescuing people trapped under the rubble of destroyed buildings.

The new work was positively received by experts in the field. Many note that the role of scales in the movement of snakes has been known for more than 60 years, but American researchers for the first time managed to put all the details of the movement of a reptile together and achieve a good agreement between the model and the real movement of the snake.

Methods of transportation

It may seem that it is very difficult to move without legs, but snakes do it masterfully. In fact, they know how to move on land in four main ways. If one method is not suitable, then they use another. Sometimes, especially on very flat surfaces, they have to try all four methods. The crawling of snakes can be quite rapid, and some of them are even capable of chasing their prey. However, even the fastest snakes rarely reach speeds exceeding 8 km/h. The crawling speed record is 16-19 km/h and belongs to.

black mamba
1. Accordion movement

One way the snake moves is called an accordion movement. First, the snake gathers its body into folds. Then, holding the tip of the tail in place, he pushes the front of the body forward. And finally tightens the back of the body.
With the help of the caterpillar movement, the snake can move in a straight line.

She uses this movement when she needs to overcome some bottleneck.
At the same time, the snake moves large scales located on its belly. One by one, the scales sink into the ground like small shovels. As soon as the scales sink into the ground, the muscles move them towards the tail.
One by one, the scales are repelled from the ground, and due to this, the snake moves. This is the same method people use when they row while on a boat. They plunge their oars into the water just as snakes plunge their scales into the ground. 3. Twisting movement

Designed to move on hard ground. To move forward, the snake bends its body to the side, resting against stones, roots, sticks or other hard objects. During this movement, snakes alternately contract the muscles on their sides, so that their body bends in an S-shape: the snake wriggles and crawls. Wave-like bending of the body is the most common way of snakes crawling.
A calmly crawling snake is an amazingly beautiful and bewitching sight. Nothing seems to happen. The movements are almost imperceptible. The body seems to lie motionless and at the same time quickly flows. The feeling of ease of movement of a snake is deceptive. It's amazing in her! This is the way he moves sand f-hole- Very dangerous snake, living here in Central Asia.

In addition to these methods, there are still some very unusual techniques movement. For example, in Indonesia, Indochina, and the Philippines, snakes from the genus Chrysopelea, a subfamily of false snakes, live. They are called heavenly for their grace and beauty. Lives paradise snake on palm trees, where it feeds on lizards.

And if she wants to change her place of residence, she flies to another palm tree.