The key to snake agility (hundreds of vertebrae and ribs) is closely related to the key to their movement - ventral scales. These specialized rectangular elements line the underside of the body, corresponding directly to the number of ribs. How does a snake crawl? The lower edges of the abdominal scales function like a tread on the tire, capturing the surface and moving the reptile forward.
Form and Functions
The most characteristic aspect of the serpentine form is the elongated body and tail, as well as the absence of limbs. There is still a snake in the world in which the remains of the limbs still retain the function of movement, but the full or reduced elements of the pelvis and thigh remain in many families, including boas and pythons. The body is usually slender, although there are some relatively short and thick species.
The shape of the body correlates with the level of activity, with subtle species, moving all the time, and severe forms, leading a sedentary lifestyle. Vipers, for example, although not always long, often large. It seems likely that these snakes developed in the direction of gravity only after the development of heat-sensitive skills, a loreal pit, a special organ located between the eye and nostrils, and a poisonous apparatus, which allowed them to stay in one place and wait for their prey, rather than engage in continuous active search food.
Some of the largest snakes (boas, anacondas and pythons) have labial pits that function in the same way as the loreal viper pit, so they too may not be very mobile and large. Tree snakes are the most elongated and slender of all, with a tail that occupies half the length of the whole body. The body is strongly compressed from the sides, which makes it possible to increase the rigidity of the body frame while crawling from branch to branch. Burrowing snake burrows are rarely large. The tail of sea snakes is flattened, forming a paddle, used for rowing through water masses. Sea snakes are almost completely helpless on land and can only move with great difficulty.
Snake Structure: Skeleton
The vertebral column of snakes is very elongated and has more vertebrae than any other living animal - up to 600 in the Australian python (Morelia oenpelliensis). Since the limbs are not connected to the skeleton, there are no good separators of the body areas, snakes, as a rule, are considered to have only two types of vertebrae: bodily (precaudal) and caudal (caudal). In the body, 100-450 vertebrae, in the tail 10-205. A pair of ribs is connected with each vertebra of the body, with the exception of several immediately behind the head.
The way a snake crawls is determined by the structure of its body. There are no ribs on the caudal vertebrae. This enables lateral and vertical rotation without interlacing the spinal column, thus achieving increased flexibility. The vertebra can carry on its ventral surface a long posterior projection called the hypapophysis. The presence or absence of this structure on the vertebrae of the posterior third of the body is of great importance in the classification of snakes, since large groups of species show this as a general characteristic.
Leather
The skin of the snake is covered with scales, which are keratinized folds in the epidermal layers of the skin. These scales are usually arranged in rows along the body, the appearance and location of which are characteristic of a particular species. They can be large and thyroid, in this case the number of rows is small (from 10 to 30), or they can be very small, round, and sometimes with a raised center, in which case the number of rows can reach 180.
The skin of a snake can be very smooth and shiny (like rainbow snakes), have a raised crest (keel) along its center, be strongly striped, or even have a raised spine in the center, like the Javanese warty snake. Scales in some species have sensory structures. On the abdominal surface of the body, in most species, it is modified into wide plates and is used for movement.
Ways of moving snakes
Snakes have four modes of movement. Since they do not have legs, they use their muscles and skin to "walk."
- Snake method: repulsion from the surface, stones, trees. They move in wavy movements. A slippery and smooth surface, such as glass, is not suitable for this method. This movement is known as lateral undulation. Starting from the neck, the snake squeezes its muscles, pushing its body from side to side, creating rows of curves. In water, this movement easily propels the snake forward, because each contraction pushes against the water. On land, the snake usually finds resistance points on the surface such as stones, branches or dents, uses its body to click on all points at once, pushing the snake forward.
- Flattening method: This is a more difficult way to move, but is effective in tight spaces. This method works well for horizontal surfaces, but snakes are raised using the accordion technique. The snake stretches its head and front of the body along a vertical surface, and then finds a place to capture abdominal scales. To reach it, she beams in the center of her body with the beams, adheres to the surface, pulls it back to the end, and then comes back forward to find a new place to capture.
- Side Impact: This is a difficult movement that snakes often use to move on loose or slippery surfaces such as sand or mud. Squeezing the muscles and throwing the body sideways creates an S-shape that only has 2 points of contact with the ground. It seems that the snake throws its head forward, and the rest of the body rushes after it.
- The straightforward (caterpillar) method: this is a slow, creeping, direct movement. How does a snake crawl at the same time? The animal uses some of the wide belly scales to grab the ground as it moves forward. This is a much slower method of movement, the waves are much smaller and bend up and down, and not from side to side. When the snake uses the movement of the caterpillar, the vertices of each curve rise above the ground while the ventral scales on the bottoms push against the ground, creating a ripple effect similar to that of a caterpillar.
Can a snake crawl in the opposite direction?
Birds do not fly backwards, fish do not swim, antelopes do not run back. Reptiles are also affected. How does a snake crawl? Each part of the abdomen has its own muscles, which the snake can use to move forward. Can snakes move in a straight line? Yes, they can, but it depends on the type of surface on which they should crawl, their speed and various other external factors. The only reason why this is not commonly seen with most snakes is simply not necessary.