What spiders are poisonous? Detailed answer

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What spiders are poisonous? Detailed answer

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What spiders are poisonous?

It is hardly possible to find a place in the world where there are no spiders. They can be seen at sea level, and on Mount Everest, in forests, in meadows, in swamps, in deserts and in holes underground. Many people are afraid of spiders because some species are known to be poisonous. All spiders, with the exception of two species, have venom glands. But this does not mean at all that spiders with poisonous glands can cause any harm to a person.

Spiders control their venom glands and use them on special occasions. For example, those spiders that weave webs to catch their victims do not use poison. Those who hunt their victims, or lie in wait for insects in flowers and seize them with their teeth, kill their prey with poison. All spiders, however, use venom for self-defense. When they are trapped and escape is impossible, poison serves as a last resort.

Very few spiders are venomous enough to be dangerous to humans. The only dangerous spider in the United States is the black widow. Its body is approximately 1 centimeter long, and it has a red hourglass-shaped mark on its abdomen. The bite of this spider can cause severe pain and cause a painful condition. Some spiders poisonous to humans live in Australia.

Large tarantulas, whose bites are considered fatal, as well as banana spiders, have not actually killed a single person. Their bite can only cause a swelling in the area of the bitten place, which can hurt for several days.

Most spiders are no more dangerous to humans than wasps or hornets. In fact, many spiders won't bite even when held in the hand. Therefore, with all spiders, except for the "black widow", you can feel completely safe. Undoubtedly, the most amazing property of spiders is their ability to weave a web. The substance from which the web is produced is formed in special glands in the abdominal part of the spider's body, and then this substance is squeezed out of the glands through many tiny holes at the end of the abdominal part. Liquid solidifies on contact with air.

The substance from which the web is made may have a different composition depending on the type of spider. The web is also of the most varied type, it can even be underwater!

Author: Likum A.

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