The value of a spider in human life. Lesson summary "variety of arachnids and their meaning"
Spiders are very useful animals that exterminate harmful insects. We humans have a bad habit of disturbing the life of the natural world for our own selfish needs. In doing so, we are destroying a lot of spider habitats. The use of insecticides in agriculture destroy entire settlements of insects and spiders. Very a large number of spiders are listed in the Red Book and are currently on the verge of extinction. It has become very rare to meet tarantulas in South America, due to the fact that they were caught and sold as pets. Nowadays, spider venom is increasingly used in medicine. Previously, they were caught in nature, now spiders are quite successfully bred in captivity. But the significance of spiders for humans is not limited to the use of their poison. People have long tried to unravel the secret of the web and make fabric from it. Someone even managed to create gloves and stockings from such a web fabric in a single copy.
Some people keep spiders in their homes as pets. Mostly non-poisonous tropical spiders become "domestic", and the tarantula is also very popular. They are kept in a small terrarium; for these purposes, an aquarium is quite suitable, which must be closed with a lid from above, leaving only small holes for air to enter.
The role of spiders is high both in the fields and in gardens and vineyards, where spiders eat leafworms, springtails, aphids, turtle bugs and other insects. It is important that spiders find pests not only on the ground, but also in the plant layer.
Despite the dislike of spiders that most people have, they still provide benefits. As predators, they reduce the number of smaller insects. Spiders serve as food for birds and other animals, especially certain types of wasps, which paralyze spiders and lay their eggs in the paralyzed body. Efforts to use spider silk for fabric were not economically successful, but silk was used for artificial hair, optical instruments. Although spiders have taken a place in various mythologies, their widespread disrepute in modern times is likely due to their tendency to hide in dark places, their sudden appearance sometimes causes unreasonable fear.
The scabies mite settles on human skin and causes scabies. This disease can be prevented by keeping household items clean, observing hygiene rules. A serious disease is transmitted by blood-sucking ticks (taiga and village) - encephalitis, tick-borne typhus. The means of protection is clothing, and the prevention of disease is vaccination.
In the evolution of spiders, the web was crucial - spiders constantly use it. They interact with the outside world through their cobweb adaptations (they build nets, settle on cobwebs, etc.). And with all the great species diversity, spiders retain unity in the features of structure, nutrition, and development. Adapting to new conditions, they changed, first of all, their cobweb adaptations.
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Scorpions of scorpions - about 10 cm. The largest of them reach a value of 20 cm. They are united by the presence of claws and a flexible tail in which a poisonous gland is placed. The cephalothorax is covered with a shield on which the eyes are located: five pairs of small ones on the sides, as well as larger ones in the middle. True, they see poorly, they mostly feel with the help of small hairs on their claws. The body of a scorpion is covered with a strong chitinous shell, which consists of a cephalothoracic shield, seven dorsal and abdominal shields and five chitinous rings defending the tail. The scorpion has six pairs of limbs, two of which are jaw organs, the rest are used for locomotion. Habitat
Scorpios prefer countries with warm climate. They live like in wet tropical forests, as well as in sandy deserts. Representatives of the scorpion family can be found in Australia, Africa, India, southeastern Europe, Asia, North and South America. former USSR 15 species of scorpions can be found. They mainly live in the countries of Central Asia and in the Crimea. However, sometimes they come across in other regions. Despite their love for the hot desert climate, scorpions are not very adapted to it. They constantly hide in various shelters and burrows, where the air is more humid. There they are better able to endure heat and dryness. Scorpions are nocturnal creatures. And at the same time of day, they hunt for various small animals (crickets, cockroaches, mice, lizards, spiders, etc.)
It is desirable to keep in terrariums. For successful content, you need to remember these things: * Scorpios require a constant change of environment. In principle, it is not so difficult to equip a terrarium (place a few large stones, some snags, small stumps), but do not forget that you need to add something new from time to time, constantly change the situation.
* Do not forget, also, about such things as - humidity and temperature. It is desirable that in different places of the soil, they are different. In one corner there should be a lamp that supplies heat, and in the opposite side a source of moisture (wet cotton wool, wet moss). Sometimes, you can also moisten the soil with water.
* Another important thing is space. Scorpios require a lot of it. For the normal existence of an adult scorpion, the dimensions of the floor must be at least 50x60 cm. Breeding
Most scorpions are viviparous, although there are some species that lay eggs. The female scorpion bears not so many offspring - from 5-6 cubs to several dozen. After birth, the young climb onto the body of the mother and stay there for several days. Here they survive the first molt and become completely independent individuals. In no case should a female and babies be separated into early stage because they are completely dependent on the mother. Immediately after the young leave the mother and begin to crawl on the substrate on their own, they must be separated and kept separately, otherwise they will try to kill each other. Scorpions become adults after 7 molts - this is approximately 1.5 years after birth.
Water is a must for a scorpion. You can spray the plants with a spray bottle and thus moisten the environment. Also, it is recommended to put a low drinking bowl, where the scorpion will crawl from time to time and quench its thirst. Scorpions are unpretentious to food - they absorb almost everything: flour worms, small earthworms, spiders, caterpillars, ants, etc. It is advisable to feed the scorpion in a box, especially worms that can run away and burrow in the substrate. Larger scorpions can be fed rodents from time to time, but do not overdo it - it can even hurt.
By eating bugs that can destroy crops, spiders serve an important function in many ecosystems. Spiders are also prey to other animals, which further increases their ecological importance, and spider silk is potentially useful for humans as a material.
Spiders are very important in checking insect and arthropod populations, and they are also food for birds, snakes, fish, and other animals, including some that humans eat. In this sense, spiders are an important part the food chain person. Although many people dislike them, spiders eat insects that could otherwise infect people's homes.
According to state university State of Pennsylvania, silk silk may prove beneficial to humans due to its durability.
Significance in nature and human life of arachnids: description, photo
If researchers can find a way to make artificial spider silk, it could be used to make everything from artificial tendons to bulletproof vests and parachute cords. Spider silk is described as "tougher than Kevlar and stronger than steel", but it is also very good, making it a very useful substance in the most different situations. Spider silk may also have fewer practical uses; it may one day be used as alternative source material for the manufacture of expensive fabrics.
From a spider, the harm to a person is small, but the benefits are great. Few of the spiders are poisonous; these, of course, are dangerous to people who live where there are many poisonous spiders. Spiders that have settled in houses clog the walls of our dwellings with cobwebs. There is no other harm.
And the benefits are great.
The value of arachnids in nature and human life
Spiders are voracious: every day they eat no less than they weigh. When the hunt is especially successful, some spiders from the genus araneus (and among them our usual cross) catch in the net for ... five hundred insects per day. Flies predominate in this catch.
And now let's calculate: in a forest or in a meadow, in a hectare space, that is, in a square of one hundred meters per hundred, often a million live (in Bryansk forests), and in some places (in England, for example) 5 million all kinds of spiders! If each spider from sunrise to sunset catches not 500 (this, apparently, is something about a record), but at least two flies (this is for sure) and let there be a thousand times fewer spiders (an average of 5 thousand per hectare) , then how many of these damned insects die every day on every square meter of our country? One fly is a minimum, and a maximum - in places where there are a lot of spiders - 250 thousand of all kinds of insects, mostly harmful.
But the fly, it only looks harmless. When they recognized her closer and examined her carefully, armed with a microscope, they were horrified. This insect is pure apocalypse! They counted 26 million microbes on the body of a single fly! And such terrible ones, from which people get sick with tuberculosis, anthrax, cholera, typhoid fever, dysentery, various worms. When the summer is hot, one fly produces nine generations of its own kind. And their number is multiplied from each unit to 5,000,000,000,000 flies! By autumn, the entire planet would have been completely littered with flies, and above these stinking blockages, myriads of flies, counted by cosmic figures, would buzz. Mankind, presumably, would all perish. Only the enemies of flies, mainly spiders, save us from such a nightmare.
The conclusion from this simple arithmetic seems to be clear: watch out for spiders! Maybe a lot of them are unsympathetic. Perhaps the human aesthetic sense finds its satisfaction in completely different living forms. Maybe ... But the intellect of a person is always the first dominant, and therefore everyone should remember: a spider is a friend to a person!
Spiders are good for us already because they destroy flies. What else are they good for?
An amazing web. And, alas, in our utilitarian age we do not dispose of it. Looking at a spider primitive learned, perhaps, to spin. And if he didn't (looking at the spider!), then it's not the spider's fault, which sets a great example here. One way or another, the method was mastered, and they began to look for material for yarn here and there: they spun from byssus threads sea shellfish Linen, famous in antiquity, was spun from the wool of goats, rams and camels. And then, suddenly, an unexpected discovery happened: one summer day, the Chinese Empress pulled the cobweb of a silkworm caterpillar that had fallen into a cup of tea with her sharpened nails - and the cobweb kept stretching and stretching! Those caterpillars were bred, tamed and surprised the world with the brilliance of precious silk.
But what is their silk compared to that with which the spiders fill our forests in prodigal abundance.
There were such experiences. This practice still exists.
"Satin of the East Sea" - tong-hai-tuan-tse, a once very durable fabric, was apparently spun from the web of not caterpillars, but spiders.
They say that in March 1665, the meadows and fences near Merseburg were covered with a great many webs of some kind of spiders, and from it "the women of the surrounding villages made themselves ribbons and various ornaments."
And later, Louis XIV, King of France, was presented with stockings and gloves woven from silky threads of French spiders by the Parliament of Montpellier. Magnificent web gloves were sent to Josephine, Napoleon's beloved, by Creoles from the island of Mauritius.
At the same time, more than a hundred years ago, flaunted in pantaloons made of cobwebs brazilian spiders famous naturalist D'Orbigny. He wore them for a long time, but they did not wear out. D'Orbigny wore them to a meeting of the French Academy. But the French Academy was not surprised by the pantaloons made of cobwebs: it had already seen such curiosities and even discussed the question of whether it was worth recommending the weaving industry as a yarn for silk.
Someone Bon, "President of the Chamber of Accounts in Montpellier", 260 years ago presented a paper to the Academy of Sciences in Paris. In it, on many pages, he described the basics of spinning and making fabrics from cobwebs, and attached two pairs of visual aids to the report: stockings and gloves.
The Academy elected a commission, which was charged with studying in detail the reality and profitability of spider sericulture and silk weaving. Reaumur, a member of this commission, found the web quite suitable raw material for industrial production, but decided that the local, French spiders did not weave threads of the required length. He calculated that it would take 522-663 spiders to process one pound of spider silk, and industrial production would require hordes of spiders and swarms of flies to feed them - more than they fly over all of France.
“However, perhaps in time it will be possible to find spiders that give more silk than those that are usually found in our state” (Rene Antoine Réaumur).
Such spiders were soon indeed found in the tropics. Travelers used to say that birds get tangled in their web! A pith helmet hangs on it - and it does not tear! So durable gossamer threads. And one spider in a month easily pulls out three or four kilometers of such threads.
These amazing spiders called nephiles. Nature did not stint either on colors or on the talents necessary for weavers, and generously endowed the nephil with them.
A spider of the Madagascar nephila, with a golden chest and fiery red legs in black "socks", spins a cobweb sparkling with gold. Huge (together with legs - with thumb), she, like a giant queen, rests on a carpet woven from golden “wool”, surrounded by nondescript male dwarfs (the female weighs five grams, and her husband is a thousand times less - 4-7 milligrams!).
Our compatriot famous Miklouho-Maclay was the first European to see and describe what a very useful application web found by people in New Guinea. It is so unusual that many people met stories about it with great disbelief. A quarter of a century after the death of Miklouho-Maclay, the collector of the British Museum of Natural History, A. Pratt, came with his son to the same New Guinean forests and lived there for two years. And this is what he said when he returned to Europe in 1904:
“There are many cobwebs of huge spiders in the forest, it is six feet in diameter. Woven in large meshes - about an inch at the edge of the web and one-eighth of it in the center. The web is very strong, and, of course, the natives quickly figured out how to profitably use it in business, forcing a large, hazelnut-sized hairy spider to serve a person.
They bend a large rod of bamboo in a loop and put it close to the web. “Very soon, the spider will braid this convenient frame” - and a great net is ready!
In the backwaters of the river, where a calm current is circling small whirlpools, they catch fish with this net: they pick it up from below and throw it ashore. "Neither water nor fish can break the mesh" - so strong.
Alas, few believed Pratt that fish were caught with cobwebs in New Guinea. But later, other researchers saw this with their own eyes in New Guinea, Fiji, the Solomon Islands and other islands. A lot has already been written about this in new books and articles. They say that even butterflies, beetles, small birds and bats enterprising children of the forests catch with nets made of cobwebs. And the fish seem to be pulled out of the water weighing a pound and two!
They also came up with another way of fishing with cobwebs. They bend a rod with a hoop, braid it with a cobweb of nefil, put bait on top - ants and their eggs - and let this set tropical pattern net go with the flow. Small fish peck the bait from below, from the water, and get tangled in the web with their gills. Down the river, hoops with a catch from the water are selected. Two or three of these floating nets can catch a dozen fish in a quarter of an hour.
Recently, finally and experimentally, the strength of the nephil web was tested. A thread one tenth of a millimeter thick can withstand 80 grams (thread silkworm- only 4-15 grams). It is so elastic that it stretches almost a quarter of its length and does not tear. A meter-long thread of a silkworm is pulled out without breaking only 8-18 millimeters.
The fabric of golden nephila web is surprisingly airy and light; with the same strength, it is much thinner than silkworm silk, and with the same thickness, it is much stronger. Cobwebs for yarn are collected from nephil nets or their egg cocoons are unwound. But it is better to pull it directly from the spider, which is put in a box - only the tip of its abdomen with spider webs sticks out of it. Elastic threads are pulled out of warts “just like a cocoon is unwound,” says J. Rostand, a great expert on sericulture. “In this way, from one spider you can get about four thousand meters of silk thread in a month.” The thread untangled from the cocoon of a silkworm, depending on its breed, is from three hundred to three thousand meters long.
Using different methods, experimenters obtained, for example, threads of this length from different spiders: 1) in two hours from 22 spiders - 5 kilometers, 2) in a few hours from one spider - 450 and 675 meters, 3) in nine "unwindings" of one spider in within 27 days - 3060 meters.
The best results were achieved by Abbé Kambue, exploring the silkworm possibilities of the Madagascar galaba spider. In the end, this inventive man managed to improve his business so much that he “connected” living spiders in small drawers directly to a special type of weaving loom. The loom pulled threads from spiders and immediately wove the finest silk from them.
They tried to acclimatize Galaba spiders at one time in France and here in Russia. But nothing came of it.
A web, even a nephil, will hardly ever enter wide production: it is not easy to maintain farms of silkworm spiders - how to feed them? Therefore, gossamer fabrics are 12-14 times more expensive than silk made from caterpillar cocoons. But for some special purposes, strong and light web yarn can be very useful. For example, for airships, which, it seems, will soon be built again. Seventy years ago, they already tried to weave a shell for airships from a web of nephil, “and it was possible,” says Professor A.V. Ivanov, “to make a sample of luxurious silk fabric 5 meters long.”
In optics and instrumentation, gossamer threads have already found application.
The benefits of spiders To a man from a spider, the harm is small, but the benefits are great. Few of the spiders are poisonous; these, of course, are dangerous to people who live where there are many poisonous spiders. Spiders that have settled in houses clog the walls of our dwellings with cobwebs. There is no other harm. And the benefits are great. Spiders are voracious: every day they eat no less than they weigh. When the hunt is especially successful, some spiders from the genus araneus (and among them our usual cross) catch in the net for ... five hundred insects per day. Flies predominate in this catch. And now let's calculate: in a forest or in a meadow, in a hectare space, that is, in a square of one hundred meters per hundred, there often lives a million (in the Bryansk forests), and in some places (in England, for example) five million all kinds of spiders! If each spider catches not five hundred from sunrise to sunset (this, apparently, is something about a record), but at least two flies (that's for sure) and let there be a thousand times fewer spiders (an average of five thousand per hectare) , then how many of these damned insects die every day on every square meter of our country? One fly minimum, and maximum - in places where there are a lot of spiders - two hundred and fifty thousand all sorts of insects. Mostly harmful 6. But the fly, it is only seemingly harmless. When they recognized her closer and examined her carefully, armed with a microscope, they were horrified. This insect is pure apocalypse! They counted 26 million microbes on the body of a single fly! And such terrible ones, from which people get sick with tuberculosis, anthrax, cholera, typhoid fever, dysentery, various worms. When the summer is hot, one fly will produce nine generations of its kind. And their number will increase from each unit to 5,000,000,000,000 flies! By autumn, the entire planet would have been completely littered with flies, and above these stinking blockages, myriads of flies, counted by cosmic figures, would buzz. Mankind, presumably, would all perish. Only the enemies of flies, mainly spiders, save us from such a nightmare. The conclusion from this simple arithmetic seems to be clear: watch out for spiders!
1. Representatives of scorpions, their habitat, food, reproduction ...
Maybe a lot of them are unsympathetic. Perhaps the human aesthetic sense finds its satisfaction in completely different living forms. Maybe ... But the intellect of a person is always the first dominant, and therefore everyone should remember: a spider is a friend to man!
So that the flies do not forget how to fly :))
To eat flies! So them, so them!
They say there is such a tradition, if a spider came to the house, then wait good news. You can't kill them!!!
Why are people needed? Spiders at least don't destroy this planet.
To limit the fly population.
To scare those who are afraid of them..
so that flies and other insects do not get people))! And tarantulas do eat birds! kill the spider, kill your happiness! (I came up with this myself!)
Millions of insects live on our planet, and they all play a big role in life. environment. Arachnophobes will be quite surprised that arachnids are an important part of human life.
Many are thoughtlessly exterminating spiders, scorpions, but why did nature actually create such terrible-looking creatures?
Why were arachnids created?
The importance of arachnids in nature and human life is quite large: they bring many benefits to people and at the same time can be carriers of dangerous diseases. Playing the role of predatory creatures, they kill insects, at the same time being part of the food chain in various animals, birds, and aquatic inhabitants. In nature, they perform the work of creating a habitat for other creatures, for example, the process of soil formation cannot do without soil mites.
In agricultural activity from arachnids comes ambulance for the control of pests that spoil seedlings in the fields and in the forest belt. This is an important feature of the importance of arachnids in nature and human life. Sometimes special predatory mites are placed indoors to conduct a biological rescue operation.
Spiders: what is the use of them
As you know, the spider web is of great benefit, for example, to catch up to four hundred insects, one spider will need only a day. Incredible, right? This means that all cobwebs on garden trees or fences, as well as shrubs, vegetable gardens, vineyards, are of great benefit for cleaning off harmful insects. Since predatory animals appear in small numbers in spring, the most good time for reproduction. Spiders are quite resistant to cold weather, so their work can last continuously all year round.
For a person, harm from a spider occurs when it braids home walls with its nets, of course, this does not look attractive at all. And the spiders themselves are not very beautiful, and some people are so scared that they develop a phobia. You need to be afraid of spiders, living in the area where they are poisonous.
The catch of a spider is usually flies, so if you are overcome by these annoying flying insects, then in no case drive out all the spiders, leave at least one. In a day, a spider can eat about as much as it weighs.
Scorpions: Should You Be Afraid of Them?
Don't be surprised that scorpions are also arachnids. Scientists have determined that this is the most ancient order of arthropods on planet Earth. Today there are about one and a half thousand different types. The Himalayan heights are the home of scorpions, and caves that go deep into 900 meters, they live in tropical jungle, in the forests of Europe and even on the seashore.
The largest species of scorpion is the imperial scorpion, whose representative can grow up to 20 cm in length.
The importance of arachnids in nature and human life is great, even if we do not see a direct benefit. Scorpions are dangerous and quite ferocious, they are especially active at night in the heat, their body picks up any fluctuation of the wind. Thanks to sensitive receptors, they can feel the touch of their future prey on the sand from a distance of about 30 cm.
If it suddenly turned out that the proposed dinner did not suit him, the scorpion takes a belligerent position to scare away the failed victim. But when the creature satisfies the scorpion, it seizes it with its pincers and strikes it with its sting. To do this, its tail acquires an arc-like structure. The value in nature and human life of the arachnid scorpion is determined as part of the food chain.
It does not help a person get rid of garden pests, but supports the theory of natural selection on the planet. After the poison enters the body, it is paralyzed and all organs gradually cease to function.
Scorpions are individual farmers, they will never share their prey, and even in too difficult conditions, if a brother is nearby, they can kill him and eat him. Despite this, these arachnid creatures can keep the body starving for up to two years, including the lack of water. But they eat up quickly, having washed the bloodworms on both cheeks, they can continue to walk around full for several months.
The rumor that there are non-venomous scorpions is false. Absolutely all individuals secrete poison, just the degree of toxicity is different for each. When a person bites, the poison immediately seeps into the bloodstream, through which it reaches the nervous system, while simultaneously polluting the entire body with strong toxins. In fact, only twenty-five species are dangerous to humans. The most poisonous is the species that lives mainly in North Africa. For example, in Tunisia. It is called Palestinian, and about 90 percent of the people whose bodies have been poisoned die from its bite. By the way, the life expectancy of such an arachnid is up to twenty-five years.
The life of pests in the human environment
Ticks are also of great importance in nature and human life, but rather negative. Spider-like small pests are most often the cause of a particular disease. With the help of a tick, a person receives a pathogen, and that, in turn, is provided with good nutrition in the form of human blood. The most famous ticks are taiga and dog species. The first spreads encephalitis, and the second tularemia and hemorrhagic fever.
Spiders are among the most important entomophages, exterminating a huge number of insects and limiting the increase in the number of some harmful species.
In addition, spiders themselves serve as food for many animals (see "Relationship with other animals. Enemies. Ways of protection.")
There are not so many spiders that are dangerous to humans compared to the total number of their species. Venomous spiders are found among various families, but they are most abundantly represented in the family Theraphosidae from the South and Central America. On the other hand, spiders that are dangerous to humans have not been found at all among such families as Gnaphosidae, Linyphiidae, Micryphantidae and in the entire Cribellatae group. It should be added that in the north and in the middle lane there are no poisonous spiders at all. Spider venom acts like strychnine, although weaker - first excitement, then breakdown and paralysis. This is a complex biochemical mixture: it contains both neurotoxic, paralyzing the nervous system, and hemolytic, blood-destroying substances. According to the nature of the poisoning caused poisonous spiders are divided into two groups: the bite of some causes local pathological reactions, the poison of others has a neurotoxic effect on the entire body of an animal or person. The bite of the latter, as a rule, causes severe pain and leads to very serious consequences, and sometimes death.
Experiments have shown that the poisonousness of spiders, in particular tarantulas, is highly variable and depends on the season, sex, age, race of the spider and the environment in which the bite was made, and even on whether the spider was crushed when it bit. It was found that the most poisonous females of a large race, in the summer, during the mating season. Perhaps the poisonousness of spiders varies depending on the geographical latitude of the area and that it is stronger in the south than in the north. But in general, despite the large number of rumors about the strong toxicity of the tarantula, there have been no official deaths from their bites. I must say that the bite of some non-dangerous large spiders that can bite through human skin can also cause unpleasant painful phenomena. For example, the bite of a female Eresus niger from Cribellatae, which is widespread in the steppe and semi-steppe zones of the former USSR, causes acute pain, quickly replaced by numbness.
The veterinary significance of the same tarantula is unclear. There is an opinion about its strong toxicity to cows. It is believed that a cow that has eaten a tarantula dies.
But spiders are much more useful. And medicine has been dealing with them for a long time. For example, the web as a plaster for wounds is used in folk medicine. Indeed, clean, fresh cobwebs have been proven to have bactericidal properties. In addition, healers use the web to treat alcoholism, but this property has not yet received scientific confirmation.
And before the discovery of America, before cinchona was found, even malaria pills were made from spiders.
But the biggest role for humans, as well as for the entire planet, is played by the voracity of spiders and the destruction of harmful insects by them, and Stegodyphusmimosarum spiders are even bred in South Africa to fight houseflies. Spiders destroy a huge number of arthropods of medical importance - bloodsuckers and carriers of pathogens of infectious diseases. The role of spiders in the extermination of the malarial mosquito is especially great.
It must be said that biological methods for the protection of agrocenoses using spiders were also proposed. They exterminate harmful insects, and, according to some researchers, various entomophages (taken together) destroy fewer insects than spiders. Thus, by creating favorable conditions for the life of spiders, it would be possible to protect agrocenoses in an environmentally safe manner. Unfortunately, this method is not used anywhere on a large scale. (Kharchenko L.N., 1997)
In addition, we must not forget about the wonderful web. There were even attempts to spin fabric from it, which turned out to be very thin, light and much stronger than silk. True, such a fabric will hardly ever enter wide production: it is not easy to maintain spider farms because of their great voracity. There have also been attempts to use spider silk for airships. But in the optical industry (for the preparation of crosshairs in telescopes, microscopes, optical sights of rifles), the web has already found its application. In addition, especially strong and lightweight compounds are made from the web - composites. Bulletproof vests made with the addition of webs are used in Germany, the USA and other countries. The program for the study of the structure and artificial synthesis of the web is funded by the US military. Similar developments are underway in our country. (Mikhailov, 1994)
In addition, the fact was established that spiders carry, without any visible changes in the body, a level of radioactivity thousands of times higher than the lethal dose of a person. It is obvious that such a phenomenal ability of spiders needs to be studied in depth. (Kharchenko, 2000)
It must be added that a person also has an influence on the spider, and by no means positive. Thus, the analysis of group diversity showed that in urbanized areas there is an impoverishment of the species composition of the spider fauna and its structural restructuring. In areas of residential complexes, as a rule, there are few web spiders, since the high dust content of the air makes it difficult to use spider traps. In general, the fairly sensitive response of spiders to changes taking place in urbanized areas affects the ratio of life forms in the community and the change in dominant groups. (Lukyantsev, 1999)
Spiders are the most numerous order of arachnids, inhabiting almost the entire planet, with the exception of areas forever covered with snow.
Spiders have occupied all habitats, however, among the representatives weaving trapping nets, there are only terrestrial forms, some of which can swim or settle through the air.
Spiders are the most important entomophages, playing one of the main roles in regulating the number of insects on the planet.
Guided by a complex chain of instincts, they have a rather complex and interesting behavior to observe, taking care of their offspring to some extent and changing their behavior during the mating season.
The main distinguishing feature of spiders, which is unique to them, is the ability to weave a web, which serves them both for building dwellings, and for breeding, and for hunting. The ability to weave a net is genetically incorporated, their shape, size and number of threads are specific for each family.
Most spiders live alone, with hostility towards other related individuals.
As it turns out, the subconscious fear of spiders, arachnophobia, is groundless for many people: there are very few species dangerous to humans compared to the total number, much more, both for humans and for all of nature. Spiders are useful.
Scorpions are the most ancient arthropods that came to land from the sea. More than 400 million years ago they lived in the waters of the oceans. Their size then reached one meter in length. After landfall, they shrank, but what is striking is that their shape remained the same. Scorpions are the most interesting object for research, but they began to study them in detail only at the end of the 19th century. Scientists still do not get tired of being surprised at how many secrets and mysteries this animal keeps.
There were legends about the habits of this "evil creature". Images of scorpions penetrated magic and astrology very early. They are present among the oldest Babylonian calendar drawings. Around 1150 B.C. e. in the circle of zodiac figures appears the scorpion man. Among the ancient Egyptians, the goddess Serket was considered the mistress of scorpions. She was depicted with the head of a scorpion or with human head but with a scorpion seated on it. These animals were painted on tombs, and the first Egyptian king to go down in history was the pharaoh or king Scorpio, who is reported in the Book of the Dead.
They were also well known to the ancient Romans and Greeks. So, the Romans had battle badges with the image of a scorpion, which is closely related to astrological beliefs. At that time, it was believed that the founders and destroyers of cities are born when a scorpion raises its sting above the horizon. The emperor and brilliant commander Tiberius was born under this sign.
One of the zodiac constellations is named after the scorpion. Ancient Greek myth says: Poseidon had a son - the legendary hunter Orion. Puffed up, he declared that he had no equal in this world, and he would kill any animal he met on the way. Before Orion had time to utter these words, an inconspicuous and inconspicuous scorpion approached his feet. He lifted his sting and stung the brave and boaster, poisoning him with his poison. The gods of Olympus were frightened by Orion's boasting and therefore rejoiced at his death. In gratitude, the scorpion was transferred to the sky and placed among the constellations of the Zodiac. Since then, to this day, Orion has been hiding from his killer. As soon as the constellation Scorpio appears in the sky, Orion disappears over the horizon. It was believed that the constellation Scorpio brings bad luck. With his appearance, autumn came to the sky: the earth was fettered by cold, rains and storms mercilessly whipped it, and wars devastated, exterminated and burned all life. According to ancient beliefs, a scorpion that appeared in a dream foreshadowed evil. At the same time, he protected from the evil eye and other troubles. Byzantine legend says that in ancient Amasia, located in the east of Asia Minor, there was a talisman in the form of a scorpion. He guarded the city from other poisonous animals and their relatives. In Africa, Persia, the Levant, scorpions were a real disaster. Even if they did not attack people, despite strict religious prohibitions, the Jews were allowed to kill scorpions on Saturdays. These animals were an invariable attribute in the experiments of sorcerers and alchemists. With their help, they tried to create various magical potions, and even gold. In the Christian religion, scorpions are typical inhabitants of the underworld.
Scorpions are not only the oldest terrestrial arthropods, but also the oldest among all animals living on Earth. Scientists have singled out these primitive arachnids into an independent class. At present, the area of distribution of scorpions encircles Earth approximately between 50 degrees north and south latitude. In ancient times, until the end of the Tertiary period, when the climate was warmer and moist forests extended to high latitudes, these animals were found on most of the land. Now there are about 1500 species and up to 800 varieties of scorpions. They live almost everywhere. They can be found in the snows of the Himalayas at an altitude of up to 5000 m, in caves at a depth of up to 800 m, in deserts and tropics, in European forests, on the shores of the seas.
In Ukraine, scorpions live in the Crimea, they were also found in the Odessa region.
Scorpions range in size from 5 to 10 cm, some species reach a length of 20 cm. The tropical emperor scorpion, which lives in Equatorial Guinea. An adult can reach a length of 8 cm. Once a specimen was found 29 cm long, counting from the tips of the claws to the tip of the sting. The smallest animals reach a size of 1.2-1.3 cm. Scientists have at their disposal ancient remains of animals up to 40 cm long.
Scorpions - ferocious predators. They usually go hunting at night, and are especially active in hot weather. They are very sensitive to all touches, vibrations of air and earth. Special receptors accurately capture odors. Scorpions feel another creature at a distance of 20-50 cm. If the prey is unsuitable, the animal assumes a threatening posture: it abruptly bends its "tail" over the cephalothorax and swings it from side to side. Well, if the victim is edible, the scorpion grabs it with its claws and stings with the tip of the tail, where it has poison. If the victim resists, he receives additional injections. At the same time, she is immobilized and dies from the poison. Scorpions eat only live prey, prefer to avoid relatives and not share with them. Here they show a rare individualism. When keeping scorpions in captivity and cramped containers, they attack their relatives and can eat each other. The ability of scorpions to almost never lose water remains a mystery. These animals almost never drink, but take moisture from food. Their body is adapted to absorb and process what they eat. In this case, the scorpion is the champion: 70% of the food consumed replenishes the tissues of its body. In poor conditions, animals "fast" for 6-7 months. They can starve from one to two years! This is surprising, but true: after eating one moth, a scorpion may not eat for several months. The poison is produced by all scorpions, but the degree of its poisonousness varies in different species. When bitten, the poison destroys blood cells and has a toxic effect on nervous system and the passage of nerve impulses. From 1500 known to science only about 25 species of scorpions are especially dangerous for humans. The most poisonous in the world is the Palestinian scorpion, which accounts for 80% of all stung and 90% dead people V North Africa(Tunisia). Its venom is equal in strength to that of a cobra. In 1946, 1933 people died in Mexico from the sting of scorpions. Until now, in this country, from 800 to 1000 people become victims of this predator every year.
They live from 8 to 25 years. This is a record for arachnids and insects. The breeding biology of scorpions is very peculiar. Mating is preceded by a "nuptial walk". For many hours, and sometimes for days, they walk, grappling with claws and raising their "tails", the female and the male. Then the male drags his chosen one to a secluded place. The most striking thing is that these arthropods are mostly viviparous. Pregnancy in a female can last from three to 18 months. This is more than many mammals. As a rule, up to 25 scorpions are born. They climb onto their mother's back and sit there for about 10 days. The female scorpion is a very caring mother, which increases survival and accelerates the growth of offspring. She catches the prey, tears it into pieces and feeds it to the kids. She also makes sure that the children do not eat each other. It is amazing, but true: scorpions, isolated for a while and then planted with several females, unmistakably recognize their mother. To become adults, scorpions go through seven molts, reaching the age of one and a half years. From the scorpion-dad at this time there is little sense. He does not bring up cubs, but he does not suffer from appetite either. short-lived love story for 20% of males it ends tragically. Most large females sting their lover and then eat him.
There are many legends and fables about the "imaginary suicide" of scorpions. For example, one of them says: if you surround him with burning coals, then, in order to avoid a painful death, he allegedly pierces himself with a sting and dies. Scientists have proven that scorpions' own poison is not dangerous. The fact is that under the influence of strong stimuli, they are able to fall into a stationary state. In science, this phenomenon is called catalepsy, or thanatosis. Having darted around in a fiery circle, the animal raises its "tail" vertically and freezes. This picture is taken for "suicide". But after a while, the scorpion "comes to life" and, if nothing threatens him, quickly crawls away.
Scientists are amazed by this fact. For orientation at night, a scorpion needs a very weak glow of stars. Studies have shown that no animal is as sensitive to light. It is impossible not to mention another mysterious feature of scorpions. Their survivability is simply amazing: only they are able to tolerate very large doses of radiation without any harm - a thousand or more roentgens! During the test of the French atomic bomb in the Sahara desert, only scorpions survived in this hell. There is something to think about! And at the same time pay tribute to the heroism of these little creatures. After all, scorpions, with their amazing ability to overcome difficulties and the thirst for survival, cause not only surprise, but also respect, as a symbol of perseverance.
