CATDOLL : CATDOLL:What are the reptiles?

Snakes belong to the order Serpentes, class Reptilia.

Long, limbs are degenerate, and the body surface is covered with scales. Most of them are terrestrial, and there are also semi-arboreal, semi-aquatic and aquatic ones. They feed on mice, frogs, insects, etc. They are generally divided into non-venomous snakes and venomous snakes. The physical signs of venomous snakes and non-venomous snakes are: the head of venomous snakes is generally triangular; there are fangs in the mouth, and there are venom glands at the root of the teeth, which can secrete venom; in general, the tail is very short and suddenly becomes thinner. The head of non-venomous snakes is oval; there are no fangs in the mouth; the tail gradually becomes thinner. Although this can be judged, there are exceptions and it should not be taken lightly. There are many types of snakes, which are distributed all over the world, and the most are in the tropics. The venomous snakes in China include the five-step snake, bamboo leaf green snake, cobra, pit viper and bungarus, etc.; non-venomous snakes include rat snakes, pythons, big red chains, etc.

The meat of non-venomous snakes is edible, and snake venom and snake gall are precious medicines, but some snakes are also protected animals.

Snakes will not actively attack people unless you hit their body. If you step on it, it will instinctively turn around and bite your foot, spray venom, and make you fall down. When people walk on mountain roads, the phrase "startle the snake by striking the grass" is very appropriate. You hold a wooden stick in your hand, and an elastic stick is best. While walking, scratch and hit the grass. If there is a snake in the grass, it will be frightened and run away. Hitting a snake with a stiff wooden stick is the most dangerous action, because the stick has a small landing area and it is not easy to knock down the snake. A soft wooden stick is elastic, and when hitting a snake, the stick is close to the ground, making it more likely to hit the snake. Hit the snake at the seven-inch point, which is the vital part of the snake. If you hit this part, the snake cannot move.

Snakes have a very powerful digestive system. Some of them digest food as they swallow it and even spit out bones.

In addition, snakes digest their food by crawling on the ground, using their bellies to rub against the uneven ground.

The venom of poisonous snakes is actually the snake's digestive juice. The digestive juice of some carnivorous snakes has a strong digestive ability and dissolves the body of the bitten animal, so it appears "toxic". Human bile also belongs to this kind of digestive juice.

Snakes have a strong appetite and eat a lot. They usually bite the prey to death first and then swallow it. The mouth can change according to the size of the food. When encountering larger food, the lower jaw shortens and widens, forming a thin film that tightly wraps the food. Snakes often start swallowing from the head of the animal, and when swallowing a small bird, they start from the top of the head. In this way, the bird's beak bends toward the bird's neck and will not pierce the snake's mouth or esophagus. The swallowing speed is related to the size of the food. A small mouse can be swallowed in 5 to 6 minutes, while a larger bird needs 15 to 18 minutes. Barton believes that the African rock python will only start swallowing when it determines the position of the prey's nose or ears. Pit vipers also have the ability to judge the head and tail of the prey.

Snakes digest food very slowly. It takes 5 to 6 days to digest each meal, but the peak of digestion is usually 22 to 50 hours after eating. If you eat a lot, the digestion time will be longer. The digestion speed of snakes is related to the external temperature. Skoczylas (1970) observed that the digestion of colubrid snakes completely stopped at 5℃, and the digestion was still very slow at 15℃, and the digestion process lasted about 6 days. At 25℃, the digestion was accelerated.

Snakes' teeth cannot bite food into pieces. The snake's digestive system, such as the pharynx, and the corresponding muscle system have great expansion and contraction capabilities.

Snakes mainly use their mouths to hunt. Non-venomous snakes generally bite their prey with the sharp teeth on their upper and lower jaws, and then quickly use their bodies to entangle the living prey to death or compress it into a relatively thin and elongated shape before swallowing it. Venomous snakes can also use their fangs to inject strong venom, causing the prey to be poisoned and die immediately after being bitten. When swallowing, the snake first opens its mouth wide, takes the animal's head into its mouth, clamps the animal's body with its teeth, and then slowly swallows it by moving its mandibles alternately from side to side. When one side of its mandible rotates backward, the teeth on the same side hook the food and send it further into the pharynx. Then the other side of the mandible rotates backward, and the teeth on the same side send the food further into the pharynx. In this way, due to the continuous and alternate backward rotation of the mandible, even very large food can be swallowed.

Some snakes that like to steal eggs will crush the eggshell with their bodies before eating. But some snakes can swallow chicken eggs or other larger eggs whole. When swallowing, they first use the back end of their bodies or other obstacles to support the egg body; then they open their mouths as wide as possible to swallow the whole egg. Interestingly, a type of egg-eating snake in the family Colubridae in Africa and India has a body structure that is specially adapted to eating eggs. The vertebrae in their necks have long and sharp ventral processes that can penetrate the back wall of the pharynx, forming 6-8 vertical rows of sharp serrations on the top of the pharynx. When swallowing the egg into the pharynx, the swallowing action of the pharynx "sawing the egg" to saw through the hard eggshell, and relying on the tension of the neck muscles, the eggshell is broken, and the yolk and egg white are squeezed into the stomach at the same time; the remaining indigestible eggshell fragments and egg membranes are pressed into a small ball and spit out from the mouth.

Crocodile

Crocodiles are vertebrate amphibians and reptiles. They are usually ferocious and violent. They like to eat small animals such as fish and frogs, and even kill humans and livestock. According to records, there are more than 20 species of crocodiles in the world. my country's Yangtze alligator, Thailand's saltwater crocodile and Lolo crocodile are all famous species. The largest crocodile breeding base in my country is the Guangzhou Panyu Breeding Farm, which covers an area of ​​nearly 70 hectares and has nearly 100,000 crocodiles, including saltwater crocodiles, Lolo crocodiles, Yangtze alligators, South American alligators, etc.

Except for a few crocodiles living in temperate zones, most of them live in rivers, lakes and watery swamps in tropical and subtropical areas, and some live in shallows near the coast. They have long faces and long mouths, and there is a saying that "the king of the world is the crocodile". Crocodiles are of great ornamental value. Crocodiles also have many medicinal and health benefits. Crocodiles are also a precious delicacy. Because of its treasures, some countries in the world are actively developing crocodile breeding.

gecko

Common name: Palace Gecko, Multi-wart Gecko, English name: Gecko, Japanese gecko, Walllizard

It is mainly produced in southwest my country and areas south of the Yangtze River Basin; it is also distributed in Japan and North Korea.

A reptile with a flat body, short limbs, and suction cups on its toes, which allows it to crawl on walls. It eats small insects such as mosquitoes, flies, and moths, and is beneficial to humans. It is also called a scorpion tiger, and was formerly known as a palace guard.

Gecko is a species of Lizard, also known as palace gecko. The body is flat dorsally and ventrally, and is lined with granular scales or warty scales. The tips of the fingers and toes are extended, and skin folds are formed underneath, which are densely covered with glandular hairs. They have the ability to adhere and can quickly crawl on walls, ceilings or smooth surfaces. Among them, there are about 20 species of the genus Gecko, 8 of which are produced in China. The common ones are multi-warty geckos, webbed-toed geckos, webbed-toed geckos and geckos. There are 4 known species of the genus Lizard in China, and there is 1 species each in the genus Semilobate, the genus Amputate and the genus Scorpion Tiger in China, which are mainly distributed in South China. Animals in this family do not have movable eyelids. When a gecko is strongly disturbed, its tail can be cut off by itself, and a new tail will be regenerated later. Geckos live in buildings and feed on insects such as mosquitoes, flies and moths. They are active at night. In summer and autumn, they often appear on walls, ceilings, eaves or electric poles where lights are shining. During the day, they lurk in hidden places such as wall cracks, under tile corners, behind cabinets, etc., and lay eggs in these hidden places. Each egg is 2 eggs. The eggs are white, oval, and the shells are easily broken. Sometimes several females lay eggs together. They are reptiles that can sing. The incubation period is more than one month.

turtle

The tortoise (Chinemys reevesii), also known as the golden tortoise, grass tortoise, mud tortoise and mountain tortoise, belongs to the class Reptilia, order Testudinata, family Testudininae, and subfamily Testudininae in animal taxonomy. It is one of the most common animals in the order Testudinata. Tortoises are distributed almost everywhere in my country, but the production is higher in the provinces in the middle and lower reaches of the Yangtze River; they are also produced in various parts of Guangxi, especially in southeastern Guangxi and southern Guangxi; they are mainly distributed in Japan and North Korea abroad.

The tortoise shell is slightly flat, the dorsal and ventral carapaces are fixed and immobile, the carapace is 10-12 cm long and about 15 cm wide, with three longitudinal ridges. There are yellow linear markings on the sides of the head and neck, the limbs are slightly flat, and the fingers and toes are fully webbed. Except for the fifth hind limb, all fingers and toes have claws at the end.

Turtles generally live in rivers, lakes, swamps, reservoirs and mountain streams, and sometimes go ashore. In the natural environment, turtles feed on worms, snails, shrimps and small fish, and also eat the stems and leaves of plants. Turtles are cold-blooded animals. When the temperature is above 150C, they are active and eat a lot, but when the temperature is below 10 degrees Celsius, they enter a hibernation state. Turtles are active frequently from April to October every year. During this period, at sunset every day, turtles begin to swim in the water to find food, and do not stop foraging until dawn. They dive into the water and often climb ashore from 10 am to 4 pm on sunny days to bask in the sun on the shore. June to August is the peak feeding period for turtles. In October, their food intake gradually decreases, and they are in a hibernation state from November to March.

In addition, turtles have the following characteristics: low reproduction rate and slow growth. A 500-gram turtle only gains about 100 grams after one year of breeding. However, turtles have strong hunger tolerance and are not easily starved to death even if they fast for several months. They also have strong disease resistance and a high survival rate. Therefore, turtles are relatively easy to raise artificially.