What kind of reptile is the snake and how did it come from?

Snakes are reptiles. Snakes are a group of animals under the phylum Chordates, reptiles, and are a class of reptiles with a fairly high degree of evolution. Snakes are the latest group in the evolutionary history of reptiles.

The earliest snake fossils were unearthed in the Mesozoic Cretaceous strata more than 70 million years ago, and are closely related to lizards. The snake is a branch that originated from the lizard and evolved from the lizard's trunk through the elongation of the body and the loss of limbs.

The snake body is elongated, divided into three parts: head, trunk and tail, and there are no limbs or claw-like hind limbs on both sides of the cloaca of lower snakes. The habitat of snakes varies depending on the species, and the habitat is diverse, some live in caves, some live on the ground, some live in trees, and some live in water.

Characteristics of reptiles: 1. The surface of the body is covered with scales or plates. 2. Adopt a typical crawling method when exercising, namely:

The limbs extend outward, the abdomen touches the ground, and the crawling forward. 3. All use the lungs to breathe, the body temperature is not constant, it will change with the temperature change of the outside world, and the chain of the limbs should hibernate in the cold winter and hibernate in the hot summer.

4. Reptiles are cold-blooded animals with vertebral vertebrates, and their body surfaces are covered with scales. 5. The heart of a climbing animal has only three ventricles. 6. The vast majority of reptiles are oviparous, but some species of eggs hatch first in the mother and then are born.

Snakes are reptiles. Snakes are a group of animals belonging to the phylum Chordates, the class of Reptiles. The body is elongated, divided into three parts: head, trunk and tail, and there are no limbs or claw-like hind limbs on either side of the cloaca transversely lobed by lower snakes.

Snakes inhabit different environments depending on the species, and the habitat is diverse, some live in caves, some live on the ground, some live in trees, and some live in water.

Further information: Snakes are ectotherms that have a body temperature that varies with air temperature, as snakes themselves do not have a well-developed thermoregulatory mechanism to produce and maintain a constant body temperature. The optimal temperature for snake activity is 20-30 °C, and the growth rate of snakes in this suitable range also rises with the temperature rises.

Air humidity also has a great influence on snakes, generally 50-70% is appropriate. The activity of snakes is closely related to outside temperature, humidity, light, and food. Under the influence of these external environmental conditions, there are obvious seasonal and diurnal characteristics.

Snakes either rely on their sense of smell to find their food, or they rely on their sight to find food. Terrestrial and arboreal snakes have a more predominant sense of smell than they see during foraging, while burrowing, semi-aquatic, or aquatic snakes have a more predominantly sense of smell than sight. The former stops feeding when their vision is blurred before molting.

The latter feeds on the molt process and can rely on their sense of smell to feed on dead animals.

Snakes are reptiles that belong to the phylum Chordates and the class of reptiles. The body is elongated, divided into three parts: head, trunk, and tail, and there are no limbs or claw-like hind limbs on both sides of the transverse lobe of the lower snakes; The whole body is covered in scales; The head morphology is varied, and the nostrils are located on the snout side, but the hydroids that live in the sea are located on the snout side; Protective hyaline outside the eyeball**, round pupils, vertically oval or horizontally oval, no re-invasive eyelids, and the lens is almost globular; elongated and bifurcated tongue; The maxilla (only snakes of the pit viper family have teeth), maxilla, palatine, pterygoids, and dentates have teeth with curved tips attached. However, the size, number, and structure of teeth vary from one snake to another.

The tail is noticeably shorter than the head.

The habitat of snakes varies from species to species. Some live in caves, some on the ground, some in trees, and some in water. The snake is an ectotherm that has a body temperature that varies with temperature because the snake itself does not have a well-established thermostat to produce and maintain a constant body temperature.

Snakes are carnivores and eat many species of animals, from invertebrates to various vertebrates. It is found all over the world except the North and South poles.

How can a snake crawl without feet? In fact, snakes not only crawl, but also crawl quite fast.

The snake is able to crawl because it has a special way of locomotion:

One is the meandering movement, in which all snakes are able to crawl forward. When crawling, the snake body makes a horizontal wavy bend on the ground, so that the back of the bend exerts force on the rough ground, and the reaction force of the ground pushes the snake body forward, if the snake is placed on a smooth glass plate, then it will be difficult to move an inch, and it will not be able to crawl in this way, of course, there is no need to worry about the snake, because in nature there will be no smooth ground like glass.

The second is the crawler movement, the snake does not have a sternum, its ribs can move freely back and forth, and there are costal skin muscles between the ribs and the abdominal scales. When the costal muscles contract, the ribs move forward, which drives the wide abdominal scales to erect in turn, that is, slightly warped, the upturned abdominal scales are like stepping on the ground, but at this time only the abdominal scales move and the snake body does not move, and then the costal skin muscles relax, the posterior edge of the abdominal scales exert force on the rough ground, and push the snake body forward by reaction, and the effect of this movement is to make the snake body crawl forward in a straight line, just like a tank.

The third way is the telescopic movement, the front of the snake body is raised, stretch forward as much as possible, when it touches the supported object, the back of the snake will follow the retraction forward, and then lift the front of the body to stretch forward to get the support, and the back part will retract forward, so that the snake can continue to crawl forward. Snakes that crawl slowly on the ground, such as lead-colored water snakes, will quickly expand and contract continuously when alarmed, speeding up the crawling speed and giving people the feeling of jumping.

In people's impression, snakes seem to crawl very fast, so there is a saying that "centipedes are hundred-legged, and they are not as good as snakes". In fact, most species of snakes can only crawl about 8 miles per hour, which is about the same speed as a human walk. But there are also fast-crawling, slender flower snakes, which can crawl 10 15 kilometers per hour, and the fastest crawling Zhijian is probably a venomous snake called Mamba in Africa, which can crawl 15 24 kilometers per hour, but they can only crawl so fast in a short period of time, and cannot crawl at this speed for a long time.

Therefore, even if the Tong envoy encounters a poisonous snake that will chase people, people will have time to avoid it. The reason why people have the impression that the snake runs fast is because the crawling speed of the snake is indeed relatively fast in an instant, especially the moment when the snake is frightened and escapes.