How and why do spiders make webs. Web riddles

In summer, starting from July, and especially in autumn, on the grasses, even on the lawns of parks, on low bushes and young pines, it glitters with dew splashed, thrown between the branches, like silk scarves - the finest work! Delicate, graceful and densely woven web. It is different, very different, and because the trapping net is arranged, you can immediately decide which spider wove it. Spiders produce a web of different varieties: inextensible and elastic, dry and sticky, with sticky droplets, straight and corrugated, colorless and colored, thin and thick, and some even weave real ropes.

Hour after hour, day after day, many explorers have sat by the web constructed by the spider, André Tilkin, French philosopher, devoted 536 pages to the web, although even 11 years before him, the German G. Peters seemed to have seen and told everything that can only be seen and told about the web of the cross. And even now, for an inquisitive mind, the web is fraught with so much new and unexpected that it is worth sitting in front of it for more than one hour. T. Savory said that: "Weaving circular networks is a performance that can be watched and watched."

Once seeing an amazing web, and next to it little spider, I wondered how such small spiders can create such beauty and how do they do it? Conducting observations of spiders and cobwebs, I set myself the goal: to study the features of spider webs, the adaptations of spiders to create cobwebs.

I was interested in the following questions:

1. Is it true that the web is a pure protein?

2. Do all spiders have the same web?

3. How does a spider weave its webs?

4. What properties does the web have?

5. Find out what a “signal thread” is. And its meaning.

To find answers, I set myself the following tasks:

1. Study literature.

2. Conduct observations in nature for spiders and cobwebs (take photographs).

3. Carry out simple chemical experiments in the school laboratory.

4. Find similarities in the schematic drawings of cobwebs with those found in nature.

1. MAGIC WEB

1. Skillful weavers

From what and how does a spider pull its web? On the abdomen of the spider, at its very end, there are spider warts. This is what made the spider a spider.

Nature works wonders, turning the juices of a spider's body into a web. Five or six different types spider glands- tubular, bag-shaped, pear-shaped - produce a web of several varieties. And her purpose is directly universal: nets and nets make her a spider, a cocoon for eggs and a house for living, a hammock for mating purposes and balls for throwing at a target, a diving bell, and a bowl for food, lasso for flies, ingenious doors for holes , and for a kind of parachute when moving downwind. On the hind limbs of the abdomen, the ducts of the spider glands open. These legs are called spider warts. With their help, the spider weaves its wonderful trapping webs. Each spider gland brings out its products - a sticky liquid that quickly hardens - through a thin chitinous tube. There are half a thousand of such tubes in the cross, and only a hundred in the spider that lives in the cellar. Spinning tools for spiders are not the same. The first pair of walking legs is the longest. With its help, the spider spins a web and communicates with its fellows. Spider thread bases are silk squirrels.

Weave: genuine art

The circular network of spiders is a very intricate thing, and its construction is not at all an easy task. Special materials and special weaving methods are used here, thought out. The spider himself thinks little about weaving a web: all his actions are entirely instinctive. The network woven by each of them has an individual pronounced character. On the web, you can find out which one, the spider wove it. The methods and main principles of building a network are almost the same for everyone. First of all, from what structures is it assembled?

There are eight of them: a frame of the first order, a frame of the second order, radii, a center, fastening spirals, a zone free from spirals, trapping spirals and auxiliary spirals, from which only nodules remain on the radii of the finished network - at the places of the former intersection of the radii and auxiliary spirals. The frame threads, especially the upper threads, are thick and not very elastic. The radii are also inelastic, while the trapping spirals, on the contrary, are very elastic - they can be stretched twice or four times, and then, as soon as the deforming force has weakened, they again shrink to their previous length. All threads are dry, except for trapping spirals, densely hung with glue droplets. That's why when I touched the web with my hands, it stuck to my fingers.

First, he stretches the frame of the first order. Its basis is usually two threads. They converge wide angle at one point, and from it they can diverge up or down - it all depends on the location of the spider. The spider, having glued the thread at the top, descends, vertically, hanging on it, up to hard object at the bottom, gluing the thread to it, and crawling up it again, not forgetting to pull the second thread out of the warts. So that she does not stick together with the first one, on which he crawls, he holds between them an additional claw of one of his fourth legs. Having risen to the starting point, he runs to the side - to the width of the upper base of the frame - and there he glues the thread that he pulled behind him. The cornerstone of the network, or the frame of the first order, is ready. It remains to weave additional threads into it so that it is stronger: after all, the whole network hangs on it. How are radii weaved?

The spider climbs to the highest point of the constructed frame, where it glues the beginning of a new thread, which will be the first diameter of the circle. It falls, pulling it down with its weight from the glands to the lower edge of the frame. Glues a thread to the frame - an elevator and crawls up it to the future center of the circle. Here the thread that was pulled along, crumples and presses into a lump and hangs it on the thread along which it crawled - this is the center of the center of the web. It crawls up again by inserting a claw between the threads (along which it crawls and pulls along), runs to the side and glues the towed web on the frame - the first radius is stretched from the center of the diameter to the frame. It crawls along it again to the center, from the center - pulls down along the diameter. The thread that it is pulling behind itself does not allow now to stick together with those held before. Having reached the lower edge of the frame, he runs to the side and ties the second radius there, on the frame. So, running alternately down and sideways, then up and sideways, tightens the entire frame with radial threads with the same angles between them. The third and, incidentally, the fourth (the center crossed randomly by threads) composite structures of the trapping net are completed.

The fifth - fastening spirals - the spider does quickly: returning to the center and from it from radius to radius, throwing them. The sixth zone, free from spirals, arises by itself, since you don’t need to work on it, just make sure that you don’t braid it by mistake. But here's the seventh and eighth structural elements require a lot of energy and attention.

The spider weaves trapping spirals from the outside to the center. To do this, he needs scaffolding on which he can spiral. They serve as auxiliary spirals; their spider weaves from the center to the edges. Moving along the auxiliary spirals from the frame to the center, with the first pair of legs, he measures the distance between the turns of the trapping spirals, which he pulls and fixes on the radii with the legs of the fourth pair. On the second and third legs it runs along the web. Trapping spirals are woven from a special material - cobwebs, thickly smeared with glue. As soon as the scaffolding-auxiliary spiral fulfills its purpose, the spider, having run about one circle along it, bites and eats it (so that the protein from which they are made does not go to waste). Therefore, by the end of the work, only knots remain from the spirals.

Spiders are forced to handle the cobweb fluid with care, since it is produced in spiders only when good nutrition and is costly to the animal. Once released and hardened, the web can no longer be retracted. Sometimes you can see that the spider, rising up, seems to absorb the web, which is getting shorter; but upon closer examination, it turns out that the spider simply wraps it around its legs or around its torso.

1. 3. As strong as steel!

Spider webs, or nets, are extremely diverse in design, but the principle of their operation is the same: the insect lingers, as indicated by the fluctuation of the web threads, their displacement or even rupture. In the flat, wheel-shaped web of the cross-spider, there is no such dense interweaving of threads as in a three-dimensional web, so that it is possible to keep prey thanks to the special properties of the fibers, not the design. They are strong enough and do not tear when strongly stretched, do not spring. The fibers of such a web can quickly contract and stretch 4 times or more.

What is the reason for such amazing properties threads? It is based on the protein keratin, which is part of the hair, wool, nails and feathers of animals. The structure of the fibers of the web, when stretched, the threads straighten, and when it is released, they return to their original position, i.e., the elasticity of the spring.

We can say that the spider web in its strength and elasticity is superior to natural silk. Its tensile strength, according to D. E. Kharitonov, is approximately 175 g/mm2 versus 33-43 g/mm2 for natural silk and 18-20 g/mm2 for artificial silk. The web of a spider is thousands of times thinner than a human hair. The fineness and strength of the fiber is measured in units called denier. Denier is the weight in grams of a thread 9 kilometers long. A silkworm filament weighs one denier, a human hair 50 denier, and a spider web filament only 0.07 denier. And this means that the web thread, which can be encircled along the equator Earth, weighs just over 300 grams. Gossamer is twice as strong as steel, stronger than orlon, viscose, ordinary nylon, and almost equal to special high-strength nylon, which, however, is worse than it, because it is much less stretchable and, therefore, breaks faster under the same load. Silk thread is one of the strongest chains in the world. Elastic, it can stretch, becoming twice as long as before, and at the same time it does not tear. Despite such a tiny diameter, it is as strong as steel! Synthesizes spider web from amino acids. It's pure protein!

2. PRACTICAL PART

EXPERIMENT No. 1. Purpose: to determine whether the web sinks in water.

Devices and materials: a container with water, cobwebs.

Course of experience: lowered the web into cold water. The web didn't sink.

Conclusion: It is of protein origin and belongs to the group of globular proteins that are insoluble in water and are not wetted by it.

EXPERIMENT No. 2 Purpose: to determine whether the web dissolves in 70% acetic acid.

Equipment and materials: glass cup, 70% acetic acid, spider web.

The course of the experiment: the web was placed in a glass cup, 70% acetic acid was dropped. The web didn't dissolve. 15 minutes passed, the web did not dissolve, after 30 minutes the web did not dissolve either. After 6 hours of experience, the web did not dissolve. Another 18 hours passed - the web did not dissolve.

Conclusion: the web does not dissolve in 70% acetic acid. But the material (web) curled up into a ball, which means it is pure protein.

EXPERIMENT No. 3 Purpose: to determine whether the cobweb dissolves in drinking soda.

Equipment and materials: glass cup, baking soda diluted with water, cobwebs.

The course of the experiment: the web was placed in a glass cup, drinking soda was dripped with diluted water. The web didn't dissolve. 5 minutes passed, the web did not dissolve, after 30 minutes the web did not dissolve either. After 4 hours of experience, the web did not dissolve. Another 12 hours passed - the web did not dissolve.

Conclusion: the web does not dissolve in an alkaline environment.

EXPERIMENT No. 4 Purpose: to determine if the web is really a pure protein.

Instruments and materials: test tube, Nitric acid transparent color, pure white web.

The course of the experiment: the web was placed in a test tube, nitric acid was dropped. cobweb dissolved nitric acid slightly yellowed.

Conclusion: the web is a pure protein.

EXPERIMENT No. 5 Purpose: to determine whether the web decomposes without air access.

Devices and materials: sealed plastic bag, branch with cobwebs

The course of the experiment: they placed a branch with a web in a transparent bag. The package was sealed tightly and hung on the balcony in the sun. We watched the web for a month. Despite the fact that the air temperature changed, the web did not change either in color or in shape, it remained the same.

Conclusion: the web is woven from a dense material. Air temperature does not affect fiber quality. The substance from which the web is formed does not oxidize in air, does not decompose without air access. So its chemical composition is pure protein.

EXPERIMENT No. 6 Purpose: to determine whether the web is of natural origin.

Devices and materials: matches, metal rod, cobwebs.

The course of the experiment: we fix the web on a metal rod with a wooden tip, set it on fire. She's on fire.

Conclusion: the web burns, not melts. This means that it is a completely natural product, without chemical impurities. With a specific smell of burning protein.

EXPERIMENT No. 7 Purpose: to determine whether the web does not deform when stretched. And does the web have a signal thread.

Devices and materials: ruler, branches, web.

The course of the experiment: we move apart the branches on which a web 2 cm in diameter is fixed, to the sides. The web stretched 0.5 mm wide. When we release the branches, the web returns to its previous position. We measure the web, it remained the same size and did not deform.

Conclusion: the web is elastic, does not deform and does not tear when stretched. This means that the thread consists of a long fiber, which the spider synthesizes from amino acids. In addition, the spider reacted to the movement of the branch - it appeared on its web, which means that the web really has a signal thread.

EXPERIMENT No. 8 Purpose: to determine whether the quality and appearance cobwebs temperature difference.

Devices and materials: sealed plastic bag, freezer, thermometer, spider web.

The course of the experiment: the web was placed in a sealed plastic bag and placed in a freezer, where the air temperature is minus 10ºС, for 24 hours. In appearance and quality (remained sticky), the web has not changed.

They hung the same package in the sun, where the air temperature was plus 20ºС, the appearance of the web did not change, remained the same. The quality of the web has not changed, it remains sticky.

Conclusion: the appearance of the web and its quality (stickiness) is not affected by a sharp drop in air temperature.

Experiment: I caught a fly, carefully planted it on the web, the fly stuck, buzzed and tried to escape. The signal thread twitched, the spider instantly ran up to the fly and approached from one side, then from the other side, doing something to the fly, and the fly began to subside, swaddled with cobweb threads. Less than a minute passed, and the fly was already tied up and did not twitch.

Conclusions: After conducting my observations, research, I found out that the spider never sits in the very center of its trapping web, it hides in some kind of shelter nearby. And from the network to the shelter, a cobweb necessarily stretches - a signal thread.

CONCLUSION.

Through experiments and observations, I came to the conclusion that the web is a protein. I learned that fiber contains amino acids that are highly hygroscopic. Protein chains are arranged along one axis and form long fibers, reminiscent of silk proteins in amino acid composition. By its origin, the web belongs to the group of globular proteins, it does not dissolve in water and is not wetted by it. It's completely natural product of animal origin, it burns, not melts.

While working, I learned that the webs are different not only in size, but also in the woven pattern. Spider web squeezes out with different speed. That the web freezes instantly. The spider weaves a thread intermittently, since the development of a web takes a lot of energy: having developed 30-35 meters of thread, it restores strength within a few days. All crosses have different nets, although all crosses have round nets and look like lace. But the webs of house spiders are completely different, they are stretched in a corner, from wall to wall, without any order. Like thin gray patches. In those spiders that live on trees, in bushes, in grass, the web threads stretch from branch to branch, from leaf to leaf, from blade of grass to blade of grass, also without much order.

I learned that spider web is stronger than steel and more elastic than natural silk. Spider webs are used in various areas creating wide range items from socks to fishing nets, and were previously used as dressings.

You can still tell a lot of interesting things about the web and spiders. After all, spider webs and the silk fibers from which they are made have not been sufficiently studied. But for starters, I think that's enough.

And now every summer I will watch them lace and take pictures. Since in the future I dream of connecting my activities with medicine, my work and my observations will be useful to me in the future, both in my studies and in choosing a profession.

Maybe in the future, spider farms will be created to create children's environmentally friendly and harmless clothes for newborns. Someday we will not use chemical compounds to kill flies, but we will use a web that does not need to be disposed of (burned, buried in the ground) and harm nature.

Seeing a spider, many of us get scared, try to destroy it. And the cobwebs that hang in the corners, on the trees?
Why and how does a spider weave it?

Let's try to figure this out.
Firstly, in the abdomen of the spider there are arachnoid glands that produce a sticky secret that solidifies in the form of threads in the air, and the abdominal limbs with movable warts form a thread, and then a fiber from the threads. With the help of comb claws and bristles on the limbs, the spider quickly glides along the web.

Why does a spider need a web:

Like a net for catching, because they are real predators. Because of the viscous liquid, a lot of living creatures from insects to birds get into their net.

When a victim falls into a trap, the victim swings the web, and the vibrations transmit a signal to the spider. He gets close to the trophy, sprinkles the digestive enzyme, coils the web into a cocoon and waits to enjoy.

For breeding
Male spiders knit lace next to the female's web, then tap with measured limbs to lure females for mating. And the female allocates a thread that helps to find an individual for mating. He, in turn, attaches his web to the main threads and signals to the chosen one that he is here, she, without aggression, descends along the fastened web to mate.

For movement
There were cases when they saw spiders on a ship located on the high seas.

Individual instances use the web as a means of transport. They climb high objects and release a sticky thread that instantly hardens in the air; and a spider flies on a cobweb with a headwind to a new place of residence.
Not very large adult spiders can climb up to 2-3 kilometers in the air and travel like that.

Like insurance
For jumpers, the web thread serves as insurance against predators and to attack the victim from it.
The South Russian tarantula always has a barely noticeable cobweb thread to find the entrance to its mink. If suddenly the thread breaks, and he lost his house, he begins to look for a new one.
And the jumper can sleep at night, thus escaping from enemies.

As a haven for offspring
To lay eggs, the female weaves a cocoon from arachnoid fiber, which provides reliability for future offspring.
The plates (main and covering) of the cocoon are woven from silk threads impregnated with a solidified substance, so they are very durable, similar to parchment.
There are cocoons that are loose and look like a cotton ball.

For lining
The tarantula covers the walls of its minks with a net so that the walls do not crumble, and builds an original mobile cover on the inlet.
catch prey

Easily brushing off the web while cleaning or walking through the forest, few people think about how and from what the spider wove it. But this is a unique creation of an extraordinary fortress. We will learn how spiders weave their web, where they get the material for it from and what it consists of, its forms and purpose, and also how this natural material can be used by a person.

What is it made of and where is it formed

The composition of the web includes the following substances:

• organic compounds- protein fibroin, of which the main internal thread consists, and glycoproteins that form nanofibers located around the main thread. Thanks to fibroin, the web is similar in composition to silk, but much more elastic and durable;
• inorganic substances - chemical compounds potassium (hydrophosphate and nitrate). Their number is small, but they give the web antiseptic properties and protect it from fungi and bacteria, create a favorable environment in the glands of the spider for the formation of threads.

In the abdomen of the spider there are arachnoid glands, where a liquid substance is formed, which exits through the spinning tubes located on the arachnoid warts. They can be observed at the very bottom of the abdomen.

A viscous liquid exits the tube and quickly solidifies in air. With the help of its hind legs, the spider pulls the thread and uses it for weaving. One spider is capable of producing a thread 0.5 km long.

Did you know? The most common cross-spider weaves the most famous round trapping net. The spider always weaves a construction of 39 rays, on which there are 35 spiral circles with 1245 fasteners. The crosses do this work at night and updatenet every 1-2 days.

What are the types

Spiders, depending on the species, can weave a different web.

The form may be as follows:

How and how long do spiders weave a web

The spider weaves the most famous round web for 0.5–3 hours. The duration of weaving depends on the size of the net and the weather. In this case, the wind usually becomes the best helper, carrying the thread released by the spider to a decent distance.

It is downwind that the web stretched between the trees is located. A thin thread is transferred air flow, clings to a nearby tree and perfectly withstands the movements of its creator.

He periodically renews the woven net, as over time it loses its ability to hold prey.

The spider usually eats old webs to provide for itself. building material necessary for weaving a new product. Automatic actions for building a network are laid down at the genetic level and are inherited.

Properties and functions

The web has the following properties:

1. Very durable. Due to its special structure, its strength is comparable to nylon, it is several times stronger than steel.
2. Internal hinge. An object suspended on a gossamer thread can be rotated in one direction for as long as you like without twisting.
3. Very thin. The spider thread is extremely thin compared to the threads of other living beings. In many families of spiders, it is 2-3 microns. For comparison, the thickness of the silkworm thread is in the range of 14–26 microns.
4. stickiness. The threads themselves are not sticky, they are dotted with drops of sticky liquid. However, to create a web, a spider emits not only a sticky, but also a thread devoid of glue particles.

Did you know? It was possible to develop a species of silkworms that produce spider silk. Researchers from America have been able to develop a technology that allows the production of silk fibers that have the properties of cobweb threads. Developments in this direction are still underway, and to establish the production of such fibers on an industrial scale at this moment impossible.

The web is necessary for the life of the spider.
It performs the following functions:

1. Refuge. The woven web serves as a good shelter from bad weather, as well as from enemies in the natural environment.
2. Creation of a favorable microclimate. For example, in water spiders, it is filled with air and allows them to be under water. They also close the shells in which they live at the bottom with it.
3. Trap for food objects. The spider is carnivorous, and its diet consists of insects entangled in a sticky web.
4. Material for creating a cocoon from which new spiders emerge.
5. An adaptation that plays a role in the process of reproduction. During mating season females weave a long thread and leave it hanging so that a passing male can easily reach them.
6. Deception of predators. Some orb-weaving spiders use it to glue garbage and make dummies to which the thread is attached. In case of danger, they pull the thread and divert attention from themselves with a moving dummy.
7. Insurance. Before attacking the prey, spiders attach a web thread to some object and jump on the prey, using the thread as insurance.
8. Vehicle. Young spiders leave the "father's house" with the help of a long thread. Spiders that live in water bodies use web weaving as water transport.

How can a person use the web

In China, the amazing strength and lightness of the web fabric is called "fabrics of the eastern sea." Polynesians use the cobwebs of large web spiders for sewing, and besides this, they also weave nets for catching fish.

Scientists in Japan have been able to create spider silk violin strings. Nowadays, scientists are striving to synthesize a material that has the properties of a spider web for use in various fields - from the production of bulletproof vests to the construction of bridges.

But science is not yet capable of creating an analogue of the substance that the spider produces. To do this, some researchers are trying to introduce spider genes to other living organisms.

Dutch biologist Abdul Wahaba El-Khalbzuri and artist Jalil Essaidi research activities synthesized a super-strong fabric, which is an organic combination of cobwebs and human skin.
Prior to this, the most durable fabric was considered to be Kevlar fibers produced by DuPont, whose strength is 5 times higher than that of steel, and the material obtained using spider threads is 15 times stronger than steel. But such a synthetic substance has a number of drawbacks that scientists are still working on.

The web is remarkable not only for its strength. The antibacterial properties of such a spider product have been used for a long time. Even in ancient times, a person used a cobweb mesh as a bandage bandage.

Such a sticky material adjoined the skin and created a barrier for bacteria and viruses to enter the wound. Many research institutions are working with the web, trying to apply its properties in medicine to create a material that can regenerate limbs.

European scientists say that within 5 years they will be able to synthesize artificial tendons and ligaments from spider webs.

Important! The use of the web in the field of medicine is primarily due to the fact that the human body does not reject the spider protein introduced into it.

AT modern world cobweb threads are used in the optical industry to designate crosshairs in optical devices, as well as threads in microsurgery. It is also known that microbiologists have created an air analyzer using the properties of spider filaments to capture microparticles from surrounding traces.
It should be noted that the study of the properties of the web will allow in the future to achieve great results in many industries, as well as contribute to the development and emergence of advanced technologies that are important for mankind.

Why doesn't a spider stick to its web?

Hunting for its victims (flies, midges and other insects), which are entangled in sticky nets, the spider itself does not stick to its own trap.

Consider the factors due to which the spider does not stick to its product:

1. Not all spider webs are covered in adhesive liquid, but only some areas that are well known to its creator. It is the circular threads that are sticky, and the central threads are not impregnated with a sticky substance.
2. The legs of the spider are completely covered with short and thin hairs. These hairs quickly remove droplets of glue invisible to the eye from the threads of the web. When the paw is located on the site of the arachnoid network, the particles of glue are on the hairs. When the spider removes the paw from the area without glue, the hairs, when sliding on the thread, return the glue particles back.
3. A special substance that coats the legs of the spider reduces the level of interaction with the adhesive, which further helps with sticking.

In the abdominal cavity of spiders there are numerous arachnoid glands. Their ducts open with the smallest spinning tubes, which are located at the ends of six arachnoid warts on the spider's abdomen. A spider-cross, for example, has about 500-550 such tubes. Spider glands produce a liquid viscous secret, consisting of protein. This secret has the ability to instantly harden in air. Therefore, when the protein secretion of the spider glands is released through the spinning tubes, it freezes in the form of thin filaments.

12
1. Spider-cross (with an open abdominal cavity)
2 Spider Web Warts

The spider begins to spin his web like this: he presses the spider warts to the substrate; at the same time, a small portion of the released secret, solidifying, sticks to it. The spider then continues to draw the viscous secret from the web tubes with the help of its hind legs. As it moves away from the site of attachment, the rest of the secret simply stretches into rapidly hardening threads.

Spiders use the web for a variety of purposes. In the web shelter, the spider finds a favorable microclimate, where it also hides from enemies and bad weather. Some spiders web the walls of the mink. From the web, the spider weaves sticky trapping nets to catch prey. Egg cocoons, in which eggs and young spiders develop, are also made from cobwebs. The web is also used by spiders for travel - small tarzans weave safety threads from it, which protect them from falling when jumping. Depending on the purpose of use, the spider can secrete a sticky or dry thread of a certain thickness.

By chemical composition and physical properties the web is close to silk silkworms and caterpillars, only it is much stronger and more elastic: if the breaking load for caterpillar silk is 33-43 kg per 1 mm 2, then for the web - from 40 to 261 kg per mm 2 (depending on the type)!

Other arachnids, such as spider mites and false scorpions, can also secrete cobwebs. However, it was spiders who achieved true mastery in weaving webs. After all, it is important not only to be able to make a web, but also to produce it in in large numbers. In addition, the "loom" should be located in the place where it is more convenient to use it. In false scorpions and spider mites raw material base cobwebs are located ... in the head, and the weaving apparatus is located on the oral appendages. In the conditions of the struggle for existence, animals whose heads are weighted with brains, and not with cobwebs, gain an advantage. That's what spiders are. The spider's belly is a real web factory and spinning devices - spider webs - are formed from atrophied abdominal legs on the underside of the abdomen. And the limbs of spiders are simply "golden" - they spin so deftly that any lace maker can envy them.

Spiders are small weaving factories, they are able to produce thin threads, from which lace is skillfully woven. Experienced lacemakers can envy their speed and skills. Where do spiders get their webs from?

If you turn the insect over and look closely, you will see tubercles on the abdomen. These are arachnoid warts that evolved from atrophied hind legs. In the abdominal cavity of the spider are numerous spider glands, the ducts of which open and close with tiny spinning tubes. Each species has a different number of them, some specimens have up to 500 of these tubes. This is a miniature "weaving factory". The glands tirelessly produce fluid. A viscous secret consists of a protein that instantly hardens when it comes into contact with air. The liquid passes through thin tubes and, having frozen, forms a web.

The spider presses the spider warts to the surface, a sticky secret flows out of them and sticks to it. Fluid continues to flow from the spider ducts. With the help of its hind legs, the spider stretches the liquid into a thin stream, which quickly solidifies, forming a cobweb.

The web is the thinnest thread ten times thinner than a human hair. It is highly durable and flexible. For example, the thread of natural silk is six times inferior to the cobweb in terms of strength.

The spider uses the web for various purposes. Carefully wrapped around the laying of its eggs, the spider protects its future offspring from predators and drying out. For cocoons, the spider uses a special web that contains an antibiotic. It is he who protects the masonry from fungi and pathogenic bacteria.

Spider webs are an excellent tool for hunting. Woven nets have a sticky middle. The insect, having fallen into the "snares", sticks, and desperately resisting, gets tangled. The spider calmly watches what is happening from the side. The fact that the nets have caught the “lunch” is known to the spider by the movements of the signal web, which he prudently brought straight to his hole. The spider eats the exhausted prey.

Trapping nets are a marvel of engineering. Arachnids have thought of everything to the smallest detail. First, they weave a frame - longitudinal and transverse threads at a certain distance. The borders of the frame are attached to a fixed surface, it can be a tree, a stone, a wall, etc. The beam support threads are shaped like a snowflake. The insect weaves them from non-adhesive material, along which the spider will come to the caught victim.

The second stage of weaving trapping nets is laying spiral threads. For these purposes, spiders use sticky material; a careless insect will stick to these threads. The coating loses its ability to adhere over time, so many spiders cover it with a fresh layer of "glue" from time to time. To weave such a structure, the spider will spend the minimum amount of web and time.

Spiders cover the entrance to the hole with a thick layer of cobwebs. Firstly, it saves from bad weather, secondly, it protects from enemies, and thirdly, the desired microclimate is created inside the hole. If the insect is cold in its dwelling, it hangs the walls of the hole with “carpets”.

Spiders do not spend all their time in a hole, sometimes they travel. Developing a cobweb, they descend along it, like on a tightrope.

A spider without a web would not live sweetly. In order for the arachnids to survive, mother nature rewarded them with a gift - the ability to produce miracle threads. Insects everywhere use their skill and, in my opinion, do not complain about their lives.