It is not known exactly when the legs disappeared during evolution in the ancestors of modern snakes, but rudimentary remains of the lower limbs can still be seen on X-rays.
Instructions
Step 1
Since all snakes are active predators, the lack of legs did not affect their speed and agility. The limbs of the snakes are replaced by scales that cover the body. Movement due to the adhesion of scales to the surface is divided into four main types.
Step 2
Rectilinear movement (caterpillar). A group of scales on the abdominal side of the animal push the snake's body forward, plunging into the surface, like the oars of a boat, the rest of the scales create an emphasis. So, one after another, the scales first protrude, then they are pressed by the force of the movement of a special group of muscles, and the snake moves forward.
Step 3
Wavy lateral movement (wriggling). The snake's body seems to flow sideways, while the lateral muscles of the body contract alternately. All points of the animal's body that are in contact with the surface constantly perform a series of successive movements, push, transfer, support. Due to these movements, a picture of rapid and easy movement is created. The number of vertebrae in snakes reaches 435, therefore, the number of bending points is approximately the same. The longer the snake, the more powerful and swift it can move.
Step 4
Lateral movement (twisting). The head of the reptile goes sideways and forward, then the body is pulled up to it. When leaning on the front part of the body, the back part is brought forward, then the cycle is repeated in reverse. The feeling is that the snake is walking. Thus, the sandy efa moves.
Step 5
Accordion movement. The body of the snake is grouped, collected in an "accordion", then the front end is pushed forward with the help of the tail. Then the animal pulls up its tail.
Step 6
Other ways of getting around. In addition to the basic movements, there are many different options for different types of snakes, they depend on the lifestyle and methods of hunting for the prey. When climbing trees, a spiral twist around a trunk or branch is used. Leaning on the tail, the snake's head is pushed to the support, catching on which the animal pulls up the tail. Snakes are able to jump, pre-curled up in rings, using the force of muscles on the principle of a spring. Paradise snake from Indochina chrysopella (false snakes) can make real flights up to 35 meters from palm to palm. Inhalation air creates an air chamber for gliding. Water snakes move, swiftly and gracefully swimming in the water column, wriggling in a horizontal plane. The speed of movement and stability in water is due to the shape of the body slightly flattened from the sides.
Step 7
The diverse and enchanting world of snakes always remains a mystery to humans. A small investigation, perhaps, slightly opened the veil of the secrets of the fast-moving predatory reptiles.
