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Indian summer is a great time of autumn, when you can soak up the last warm rays of the sun of the year, enjoy the excellent weather, and see the past summer. But, as usual, a barrel of honey should spoil something. Web. She is everywhere. It poisons my happiness, scares and spoils the mood. She's annoying! The web hurries to meet me in the most unexpected places, even where someone passed in front of me a minute ago, even where there is no vegetation nearby.

And they also say that the web is an incredibly strong and durable material. How does a spider weave a web that spreads it everywhere?

Spider web weaving algorithm

I read it, it turns out creating gossamer lace is a very laborious process for eight-legged creatures (spiders, by the way, cannot be called insects). They work like this:

• having chosen a suitable place, a special secret is isolated from the spider web warts located on the abdomen, which, congealing, is transformed into a long, thinnest thread;
• waiting when the breeze will pick up this thread and carry it to some kind of support - twigs, blades of grass, leaves, etc. and crawl to the place where the thread is hooked, securely fasten it;
• form another thread repeating the first, fix it;
• crawl to the middle of the second thread and form the third thread, placing it perpendicular to the first two, and fix it so that a figure resembling the letter Y is formed.

This is the basis of the future web. Then the spider stretches several more radii from the point of intersection of the threads, connecting their ends with segments of the thread. It turns out the skeleton of the web, peculiar ribs with edging. Further, fluttering over this blank, the spider quickly knits a lace pattern on it.

Patterns are created using two spirals. The first, not sticky, spider weaves from the middle of the warp, and it exactly repeats the shape of the logarithmic spiral. The second, sticky, weaves in the opposite direction and exactly repeats the shape of the Archimedean spiral.

Web types

There are 35 thousand varieties of spiders on the planet. Not all eight-legged creatures weave tight webs.

Some representatives weave a tiny mesh of cobwebs between its paws, they wait for the prey and throw a prepared sticky net on top of it. And there are representatives who do not bother with weaving at all. They catch the prey homemade spider web lasso with a drop of sticky substance at the end. There are species that work together weaving cobwebs over vast areas.

What is web used for

The most common web function is catching prey for food. But this is far from its only purpose.

Another web is used:

• to protect the home;
• as a home decoration;
• for cocoons in which females lay eggs;
• as a means of transportation.

It is the last point that explains the fact of the autumn invasion of the flying web. So young spiders settle in the area.

Appearance

In general, female goliath tarantulas are usually larger than males. The size of their soft body reaches 9 cm, while in males it is no more than 8 cm. The leg span of these giant spiders ranges from 25 cm to 28 cm. The largest individuals weigh about 150 grams.

The protective color of tarantulas varies from black to yellow-orange. This usually happens just before the molt. The cephalothorax of these creatures, as well as their abdomen, are covered with short but dense hairs. The paws are covered with long and reddish hairs.

Where does the world's largest spider live?

The favorite places of these creatures are mountainous regions with dense and humid forests. The optimal habitat for these "giants" is humid and swampy areas, mainly located in the Venezuelan rainforests. In addition, goliath tarantulas are widespread in the rainforests of Guyana, Suriname and Brazil.

Goliath tarantulas inhabit entire burrows up to 1 m deep. Outside, they braid them with thick cobwebs to prevent strangers from getting inside. Females spend most of their lives in burrows. They only come out to hunt at night. And this despite their impaired vision.

Hunting

The goliath tarantula is a carnivorous spider. Before attacking a potential victim, this creature lurks in an impromptu ambush. So the spider lies in wait for his "dinner". As soon as the future prey has approached a distance sufficient to attack, the tarantula pounces on it, using its fangs.

Contrary to its name, the tarantula does not eat birds at all. This was apparently an isolated case. The fact is that this type of spider from the order of arachnids was first noticed precisely when, for some reason, it ate a bird. Zoologists who have been observing goliaths for a long time have come to the conclusion that the favorite and main food of these creatures are both invertebrates (butterflies, beetles) and vertebrates (mice, small snakes, frogs).

Lifespan

In general, zoologists call adult tarantulas individuals who have reached the age of three. The average life expectancy of a male goliath is 6 years. The female lives twice as long - up to 14 years. It is curious that often the life of males ends after mating with a female.

The fact is that during mating games, goliath tarantulas, like praying mantises, have a ritual: after mating, the female simply eats her “groom” without his consent. However, not all spider suitors are willing to put up with this state of affairs. That is why nature rewarded them with sharp spikes located on the first pair of limbs. They serve as protection against aggressive females.

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 of 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.

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 carried by the air stream, clings to a neighboring 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 the old web to provide itself with the building material needed to weave 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.

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 the 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 have synthesized a super-strong fabric, which is an organic combination of cobwebs and human skin, through research activities.

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.

In the 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.

Video: about the web of spiders So, the web is synthesized in the spider glands located on the abdomen of spiders, and has a predominantly protein composition. These arthropods weave it for different needs, and it comes in a variety of forms. Moreover, it has extraordinary properties that humanity can use for its own purposes. Scientists from different countries are trying to synthesize a substance similar to it.

The abdomen of a spider is a real "factory" for the production of webs. It is in it that the voluminous arachnoid glands are located, which produce a sticky secret that quickly hardens in the air. The abdominal limbs form a web thread, and movable web warts guide the thread to the right place.

The abdomen of spiders is movably connected to the cephalothorax by a thin bridge. Mobile and limbs, consisting of 7 segments. As a result, the spider's organism is able to produce a web thread and quickly eliminate gaps in the trapping web. Comb claws and bristles on the limbs help the spider to quickly slide along the web thread, like a wagon on rails, allowing it to appear in time at the place where the web breaks.

Why do spiders build a trapping web?

The ability to develop patina is not the main feature of spiders, however, weaving a trapping web has become a hallmark of arachnids. Spiders are real predators, waiting for their prey in a secluded place.

Due to the adhesive properties of the web, a wide variety of animals, ranging from insects and even small birds, get into spider webs.

Having stuck to the web, the victim tries to get out of the trap, swinging the web thread. The vibrations that have arisen are transmitted along the signal thread to the spider, which quickly approaches the prey along the threads and injects the digestive juice, which, when it enters the victim, digests the internal contents. Then the spider braids it with a web, forming a kind of cocoon. It remains to wait a bit until the digestive enzymes make it possible to simply suck out the liquid contents.

Spiders need webs for reproduction.

During the breeding season, the web thread allocated by the female allows the partner to find an individual of the opposite sex for mating.

In the vicinity of the females' nets, males construct miniature mating laces, into which they lure spiders for mating, rhythmically tapping their limbs.

Male cross-spiders attach their web to the radial threads in the trapping web of the female, placing it horizontally. The male then strikes with his limbs, causing hesitation. This is how spiders signal the female of their presence. The female does not show aggression in this case and descends to the male for mating along the attached web thread.

The web is a safe haven for offspring

The female lays her eggs after fertilization in a cobweb cocoon woven from one or more silky threads. The cocoon itself is formed by 2 plates - the main and covering plate, connected by their edges. This structure of the cocoon provides reliable protection for the eggs.

The female first weaves the main plate, similar to the spermatic web for eggs. From above wraps them with a second layer of cobwebs, which forms a covering plate. The shell of the cocoon is formed by silk threads tightly adjacent to each other and saturated with a frozen secret. The walls of the cocoon become very dense, almost like parchment. In some species of spiders, the female spins a loose cocoon, similar to a ball of cotton wool.

Web as a vehicle

Some types of spiders use webs to move through the air. Spiders climb higher on a tree, a fence, a high stone, the roof of a building, raising their abdomen, they release a sticky thread. It quickly freezes in the air and the spider, having unhooked, goes flying on a light cobweb, which is carried by the oncoming air flow. So young spiders get to new habitats.

There are known cases of the appearance of spiders on the deck of a sea vessel sailing in the open sea far from the coast.

Adult spiders in species with small sizes can also migrate. Spiders are able to rise with the help of a cobweb, picked up by the wind, to a height of up to 2-3 kilometers. Moreover, spiders most often make their travels on quiet and calm days of the "Indian" summer. They cover great distances.

How different types of spiders use the web

In nature, web spiders weaving trapping nets (nets) live, but non-net species are also known that hunt without using a cobweb. But they develop a web during periods of molts, rest, molts, wintering. Spiders weave protective bags or shelters woven from cobwebs.

Tenetnik spiders are saved when a predator approaches on a cobweb, falling down. When the danger has passed, they return back to the web thread and rise up, quickly winding their safety rope.

The web is needed for insurance

Jumping spiders use web thread to attack. They attach a safety thread to an object and jump on the intended victim. The South Russian tarantula, leaving its hole, pulls a barely noticeable web thread along which it will always find the entrance to the abandoned shelter. When the insurance breaks, the tarantula is unable to find its mink and goes in search of a new one. Jumping spiders on cobwebs attached to the substrate spend the night. This is a kind of insurance against predators.

The main task of the web is to capture prey.

The web is used for lining

Tarantulas live in burrows, the walls of which are constantly crumbling, so these hairy spiders line the walls of their dwellings with cobweb threads. This design protects the earthen walls from shedding. Spiders before entering their hole weave a variety of web structures in the form of funnels, tubes, movable lids that cover the entrance.

Spider bell for breathing

The silver spider hunts in water in which it is necessary to breathe atmospheric air. Sinking to the bottom, the spider captures a portion of air at the end of the abdomen in the form of a small bubble. On plants, he builds an air bell in which the air is held by a densely woven web.

The silver spider "seals" the oxygen molecule into a web under water, and thus breathes.

Web - to catch the victim

To catch prey, spiders weave trapping nets, but some species use spider lasso and threads.

Tarantulas, having caught prey, keep it in chelicerae, then pack the victim in a web.

Spiders that hide in the depths of the hole leave a signal thread. It stretches from the abdomen to the entrance to the shelter. The vibrations of this thread are transmitted to the spider, giving a signal that prey has been caught.

The web is produced not only by spiders, but it is they who most widely use spider silk, that the weaving of the web is their distinguishing feature.

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Most types of spiders spin webs, but not all, such as tarantulas. Many tarantulas burrow into the ground and release a bit of web, covering the entrance to the "cave" to make it easier to catch flying insects. All spiders, whether they spin webs or not, have a few things in common: they have eight legs, and they all feed on insects. Remember that spiders themselves are not insects.

Spiders belong to arachnids, or arachnids - these are animals, which include ticks and scorpions in one group. There are about 40 thousand species of spiders.

Why is a web needed?

They can weave very simple products, or weave real works of art. Even when the web is ready, the spider does not settle in it forever. The spider itself can lurk under roofing shingles or in the corner of a window frame, or under a rock. The purpose of the web is to catch insects. It may take several hours to weave a quality web.

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How do spiders weave webs?

For example, a weaver spider uses several types of threads to build a web. To create a foundation, so to speak, a frame, he highlights a dry web. And in order to catch insects, the weaver puts a sticky web on the base. The web thread (a kind of "silk") is secreted by special glands on the spider's abdomen. Different glands secrete different types of silk. The spider can, depending on the purpose of weaving the web, use one or another web material.

The round spider begins weaving the web, throwing the thread into the wind. The silk flies in the wind and clings to something, such as a tree branch, which allows the spider to climb up this thread and add another thread to the original one to make it stronger. After the spider has made the general contours of the web, he spins a thread connecting one side of the web to the other. From the center of this connecting thread, the spider begins to weave another thread that will connect the center of the web to the side thread.

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Then the spider will put a lot of connecting dry threads from the edges of the web along its radii to the center, like spokes in a bicycle wheel. Then these "knitting needles" are braided with circular threads. It turns out a spiral dry web. Then an adhesive thread is applied to the surface of the dry web. Now the spider gets rid of the dry web - eats it. The fishing gear is done, the insect snares are ready.

Web construction

The design of the web, according to experts, varies depending on the method of hunting. To us, the entire web seems to be the same and made up of perfectly standard elements. Such a deceptive impression is created because we do not see the web in ultraviolet light.

Despite all the dislike of mankind for spiders, as well as the abundance of prejudices and terrible stories associated with them, the question of how a spider spins a web appears in kids almost simultaneously with interest, and the water is wet. The result of the labor of these unattractive animals really often resembles elegant lace. And if the spiders themselves are unpleasant to look at, and many are even afraid of them, then the web created by them involuntarily attracts attention and causes sincere admiration.

Meanwhile, not everyone knows that such "curtains" are not woven by all representatives of the detachment. Almost every species is able to create a thread for the warp, but only those that hunt with traps make trapping nets. They are called shadows. They are even separated into a separate superfamily "Araneoidea". And the names of spiders weaving hunting nets have as many as 2308 items, among which there are also poisonous ones - the same and karakurt. Those who hunt, attacking from an ambush or tracking down prey, use the web exclusively for domestic purposes.

The unique qualities of spider "textiles"

Despite the small size of the creators, the features of the web cause some envy on the part of the crown of nature - man. Some of its parameters are incredible even with the achievements of modern science.

1. Strength. The web can break from its weight only if the spider spins it 50 meters long.
2. Exceptional subtlety. A separate cobweb is noticeable only when it hits a beam of light.
3. Elasticity and elasticity. The thread is stretched without breaking by 2-4 times, and without loss of strength.

And all these qualities are achieved without any technical equipment - the spider manages with what nature has provided him with.

Types of cobwebs

It is interesting not only how the spider weaves a web, but also the fact that it manages to produce its different "grades". Roughly speaking, they can be divided into three types:

Scientists also highlight another type of web that mirrors ultraviolet light, luring butterflies. Many believe that the finished web necessarily has its own pattern. However, this is not so: the names of spiders capable of creative delights can be counted without much difficulty, and all such artists belong to the araneomorphic representatives of this order of arthropods.

What is she for?

If you ask a person a question why a spider needs a web, he will answer without any doubt: for hunting. But this does not exhaust its functions. Additionally, it is applied in the following areas:

• for warming minks before wintering;
• to create cocoons in which offspring mature;
• to protect from rain - spiders make a kind of canopies from it to prevent water from entering the "house";
• for traveling. Some spiders move on their own and escort children out of the womb of the family on long cobwebs carried away by the wind.

Formation of building material

So, let's figure out how a spider weaves a web. On the abdomen of the "weaver" there are six glands, which are considered to be transformed rudiments of the legs. Inside the body, a special secret is produced, which is commonly called liquid silk. As it exits through the spinning tubes, it begins to harden. One such thread is so thin that it is difficult to see it even under a microscope. With paws located closer to the currently “working” glands, the spider twists several threads into one cobweb - approximately the way women did in the old days when spinning from a tow. It is at the moment when the spider weaves the web that the main characteristic of the future web is laid - stickiness or increased strength. And what is the mechanism of choice, scientists have not yet figured out.

Stretch technology

For its effectiveness, a trapping net must be stretched between something - for example, between branches. When the first thread is made long enough by its maker, he stops spinning and spreads out the spinning organs. So he catches the wind. The slightest stirring of the wind (even from the heated earth) carries the cobweb to the neighboring "support", for which it clings. The spider moves along the "bridge" (most often sagging back down) and begins weaving a new radial thread. Only when the base is fixed, he begins to move in a circle, weaving sticky transverse lines into it. I must say, spiders are very economical creatures. They eat up the damaged or old web that has turned out to be unnecessary, letting “recyclable materials” into the second round of use. And it becomes old, according to the creator, rather quickly, since the spider often spins a web every day (or night, if he is a Shadowhunter).

What do spiders eat

A fundamentally important question, since the spider weaves a web, first of all, for the extraction of food. Note that without exception, all types of spiders are predators. However, their diet is highly dependent on size, hunting methods, and where they live. All web (weaving webs) spiders are insectivorous, and their diet is based mainly on flying forms. Although if a crawling character falls onto a web from a tree, its owner will not disdain them. Those who live in burrows and close to the ground eat mainly orthopterans and beetles, although they may drag a small snail or worm into their shelter. Among the variety of what spiders eat, there are also larger objects. For a water representative of a tribe called Argyroneta, crustaceans, aquatic insects and fish fry become victims. Exotic giant tarantulas prey on frogs, birds, small lizards and mice, although the same insects make up the majority of their diet. But there are also more finicky types. Individuals of the Mimetidae family prey only on spiders that do not belong to their species. The huge tarantula Grammostola eats young snakes - and destroys them in amazing numbers. Five families of spiders (in particular, Ancylometes) fish, and they are able to dive, swim, track down prey and even pull it onto land.