According to scientists, out of three thousand species of poisonous snakes, 450 are dangerous for humans. Poison for them is a defense, a hunting tool and even a means for digesting food. Species of poisonous snakes are distributed mainly in the warm tropical regions of the planet. There they pose a real danger to people due to their large numbers. The sad statistics of fatal bites puts Africa, Indochina and South America in the first place. Cases of death from snake bites in Europe and the CIS are rare. In the CIS, most of them occur in the Caucasus and Central Asia. In total, 11 species of snakes dangerous to humans live in the CIS.
Different types of snakes have poison of different composition, action and strength. But, despite the differences, there is a unit for measuring the strength of the poison. This is DL50, where the letters are an abbreviation of Latin words meaning “lethal dose” in translation. It is expressed in the concentration of dry snake venom (mcg / g - micrograms per gram), which is enough to kill a mouse. Oxyuranus microlepidota from Australia is now considered the most venomous.
Poisonous are not only land-dwelling snakes, there are also poisonous marine species of snakes. The degree of danger of a bite dependsnot only on the strength of the poison itself, but also on its amount, which the snake can introduce into the body. The record here belongs to the king cobra and the bushmaster. Types of snakes have been discovered that do not have poisonous teeth, which usually introduce poison. Their saliva is poisonous, it is just as dangerous to humans.
Some snakes have venomous glands, such as the king snake, common in Southeast Asia. Its entire body is covered with glands up to the tip of the tail. The king asp comes out to hunt at night and moves under the fallen leaves, making it very hard to spot.
But not all venomous snakes lead such a secretive lifestyle. Russell's viper, also known as a spectacled snake, does not hesitate to crawl even into a person's dwelling. Although her food is rats, frogs, poultry, she has caused the death of so many people. She has a frightening appearance, on the opening hood there is a bright pattern resembling glasses in shape.
How does snake venom work? Types of snake venoms differ in the nature of their effects. Some coagulate blood in the vessels, others cause paralysis and convulsions, affecting the nervous system and brain. Interestingly, the poison does not harm the snake itself. This is the result of evolution, because poisonous species of snakes did not appear overnight. The poisonous glands that are in the mouth appeared from the altered salivary glands, in the course of natural selection, which lasted for millennia, the most poison-resistant specimens remained.
Poisonous snakes have enemies that feed on them: the brave, agile mongoose, Africansecretary bird and, finally, our usual hedgehog. These animals also adapted and became less susceptible to poison, although it does affect them, but much weaker. Therefore, when hunting, they dodge the bite.
But snakes are only immune to their own venom. If a viper and a viper meet in a deadly duel, one of them will die.
Snake venom for humans is not only evil, it has long been used in medicine as a valuable medicine. Many nurseries have been created for breeding snakes, where the so-called milking takes place periodically. So the existence of poisonous snakes is necessary both from the point of view of biological balance and benefit to humans.
