Representatives of the arachnid order can be found everywhere. They are predators that prey on insects. They catch their prey with the help of a web. This is a flexible and durable fiber, to which flies, bees, mosquitoes stick. How a spider weaves a web, this question is often asked at the sight of an amazing trapping web.

What is a web?

Spiders are one of the oldest inhabitants of the planet, due to small size and specific appearance they are mistakenly considered insects. In fact, these are representatives of the order of arthropods. The body of a spider has eight legs and two sections:

  • cephalothorax;
  • abdomen.

Unlike insects, they do not have antennae and a neck that separates the head from the chest. The belly of an arachnid is a kind of web factory. It contains glands that produce a secret consisting of a protein enriched with alanine, which gives strength, and glycine, which is responsible for elasticity. By chemical formula the web is close to the silk of insects. Inside the glands, the secret is in a liquid state, and hardens in the air.

Information. caterpillar silk silkworm and cobwebs have a similar composition - 50% is fibroin protein. Scientists have found that the thread of a spider is much stronger than the secret of caterpillars. This is due to the peculiarity of fiber formation

Where does a spider's web come from?

On the abdomen of an arthropod there are outgrowths - arachnoid warts. In their upper part, the channels of the arachnoid glands that form the threads open. There are 6 types of glands that produce silk for different purposes (moving, lowering, entangling prey, storing eggs). In one species, all these organs do not occur simultaneously; usually, an individual has 1-4 pairs of glands.

On the surface of the warts, there are up to 500 spinning tubes that supply a protein secret. A spider spins a web like this:

  • spider warts are pressed against the base (tree, grass, wall, etc.);
  • Not a large number of the squirrel sticks to the chosen place;
  • the spider moves away, pulling the thread with its hind legs;
  • for the main work, long and flexible front legs are used, with their help a frame is created from dry threads;
  • the final stage in the manufacture of the network is the formation of sticky spirals.

Thanks to the observations of scientists, it became known where the spider's web comes from. It is released by mobile paired warts on the abdomen.

Interesting fact. The web is very light, the weight of the thread that wrapped the Earth around the equator would be only 450 g.

The spider pulls the thread from the abdomen

How a trapping network is built

Wind - best helper spider in construction. Taking a thin thread from the warts, the arachnid puts it under the air current, which carries the stiffened silk to a considerable distance. This is the secret way how a spider weaves a web between trees. The web easily clings to tree branches, using it as a rope, the arachnid moves from place to place.

A certain pattern can be traced in the structure of the web. It is based on a frame of strong and thick threads arranged in the form of rays radiating from one point. Starting from the outer part, the spider creates circles, gradually moving towards the center. Surprisingly, without any adaptations, it maintains the same distance between each circle. This part of the fibers is sticky, it is in it that insects will get stuck.

Interesting fact. The spider eats its own web. Scientists offer two explanations for this fact - in this way, the loss of protein is replenished during the repair of the trapping network, or the spider simply drinks water hanging on silk threads.

The complexity of the web design depends on the type of arachnid. The lower arthropods build simple networks, while the higher ones build complex geometric patterns. Estimated to build a trap of 39 radii and 39 spirals. In addition to smooth radial threads, auxiliary and trapping spirals, there are signal threads. These elements capture and transmit to the predator the vibration of the caught prey. If a foreign object (a branch, a leaf) comes across, the small owner separates it and throws it away, then restores the network.

Large tree arachnids pull traps up to 1 m in diameter. Not only insects, but also small birds get into them.

How long does a spider spin a web?

The predator spends from half an hour to 2-3 hours to create an openwork trap for insects. Its operation time depends on weather conditions and the planned size of the network. Some species weave silk threads daily, either in the morning or in the evening, depending on their lifestyle. One of the factors for how much a spider weaves a web is its appearance - flat or voluminous. A flat one is a familiar version of radial threads and spirals, and a voluminous one is a trap made from a lump of fibers.

The purpose of the web

Thin nets are not only traps for insects. The role of the web in the life of arachnids is much wider.

Catching prey

All spiders are predators that kill their prey with poison. At the same time, some individuals have a fragile physique and can themselves become a victim of insects, for example, wasps. They need shelter and a trap to hunt. Sticky fibers perform this function. Once caught in the net, they envelop the prey in a cocoon of threads and leave it until the injected enzyme brings it to a liquid state.

The silk fibers of arachnids are thinner than a human hair, but their specific tensile strength is comparable to that of steel wire.

reproduction

During the mating season, males attach their own threads to the female's web. Inflicting rhythmic blows on the silk fibers, they inform the potential partner of their intentions. The courting female descends into the male's territory to mate. In some species, the initiator of the search for a partner is the female. She secretes a thread with pheromones, thanks to which the spider finds her.

home for posterity

Cocoons for eggs are woven from silk cobwebs. Their number, depending on the type of arthropods, is 2-1000 pieces. Spider sacs with female eggs are hung in a safe place. The shell of the cocoon is strong enough, it consists of several layers and is saturated with a liquid secret.

In their burrow, arachnids weave the walls with cobwebs. This helps to create a favorable microclimate, serves as protection from bad weather and natural enemies.

moving

One of the answers why a spider spins a web is that it uses threads as a vehicle. To move between trees and bushes, to quickly understand and descend, it needs strong fibers. For flights over long distances, spiders climb to elevations, release a quickly solidifying web, and then, with a gust of wind, are carried away for several kilometers. Most trips are made in warm weather. clear days Indian summer.

Why doesn't a spider stick to its web?

In order not to fall into its own trap, the spider makes several dry threads for movement. I am well versed in the intricacies of networks, he safely approaches the stuck prey. Usually in the center of the trapping net there is a safe area where the predator is waiting for prey.

The interest of scientists in the interaction of arachnids with their hunting traps appeared more than 100 years ago. Initially, it was suggested that their paws had a special lubricant on them to prevent sticking. The theory has never been confirmed. Shooting with a special camera of the movement of the spider's legs along the fibers from the frozen secret gave an explanation for the mechanism of contact.

A spider does not stick to its web for three reasons:

  • many elastic hairs on its paws reduce the area of ​​​​contact with the sticky spiral;
  • the tips of spider legs are covered with an oily liquid;
  • movement occurs in a special way.

What secret of the structure of the legs helps arachnids avoid sticking? On each leg of the spider there are two supporting claws with which it clings to the surface, and one flexible claw. When moving, he presses the threads to the flexible hairs on the foot. When the spider raises its paw, the claw straightens and the hairs repel the web.

Another explanation is the lack of direct contact between the arachnid's leg and the sticky droplets. They fall on the hairs of the foot, and then easily flow back onto the thread. Whatever theories zoologists consider, the fact remains that spiders do not become prisoners of their own sticky traps.

Other arachnids can also weave webs - ticks and false scorpions. But their webs cannot be compared in strength and skillful weaving with the works of true masters - spiders. modern science not yet able to reproduce the web synthetically. The technology of making spider silk remains one of the mysteries of nature.

As a spider weaves a web, experts shot a video where you can see in detail the actions of an arthropod. The ability to weave an openwork fabric, funnel-shaped nets, cocoons for larvae is transmitted genetically. The young spider repeats all the actions of his mother, never seeing how it is done. Spiders make the web different in shape, size, structure, used for different purposes.

Spider web composition

It is the secret of the spider glands. After isolation, it stretches, hardens in the form of thin threads. In the future, they are intertwined, made stronger. Used to form a pattern or as a building material.

What does the spider's web consist of - a protein enriched with alanine, serine, glycine. Inside the spider gland, the substance is in liquid form. In the process of passing through the spinning tubes, it hardens, turns into a thread.

Where does the spider web come from - from warts located near the genitals. A crystalline protein is formed inside the thread, which increases the strength and flexibility of the fibers. Depending on the purpose for which the web will be used, the thickness and strength change.

Interesting!

The strength of the spider's web is close to nylon, it retains tension when stretching, compressing the threads. An object suspended on a long web can be rotated for a long time in one direction, it will not get tangled, it will not even show resistance when moving. Thanks to this feature, the spider can hang in the air for a long time, attaching the end to the plant, and also over long distances with the help of gusts of wind.

Why does a spider weave a web - main functions

The web is allocated not arbitrarily, but when the need arises. Different people use threads for different purposes, but absolutely all females use a special secret to attract males.

  • If you carefully consider where the female releases the web, you will notice that the warts with a secret are located near the genitals. A sexually mature female additionally releases odorous substances, the smell of which is captured by the male.
  • The family weaves trapping nets. The creation of large specimens within a radius reaches 2 m. The density of the canvas is such that a bird, a small rodent, and amphibians get entangled in it. Insects and their larvae get entangled in the nets.
  • Soil, underground specimens build burrows in the ground with numerous labyrinths. Trapping nets do not build, but protect the entrance with a cobweb, pull signal threads. By their vibration, they determine the approach of a potential victim, they instantly go hunting.
  • Spiders live apart, gathering in pairs only for mating. Possessions are divided, when borders are violated, deadly fights occur. For resettlement, development of a new area, the spider weaves a strong long thread, attaches it to a leaf, twig, goes down, waits for a gust of wind. Through the air, an arthropod can fly several hundred kilometers or land under a neighboring bush. Active migration begins after the birth of a young generation of spiders.
  • After fertilization, the female begins to form a cocoon from the web. Lays inside from 50 to 1000 eggs. It fixes in a secluded place or drags along the entire period of development of the larvae.
  • From strong threads, the arachnid builds a house for itself, a shelter for wintering. Unique Creature- builds a nest under water. Initially, it weaves a house of threads, fills it with air, lives inside, lets the male into mating season, hatches cubs there, drags inside the caught victim.
  • A predator wraps its prey in a web after injecting a toxin. After that, he leaves the prey, watches it aside until the convulsions stop. If the predator is not hungry, it hangs the caught prey on a web in a secluded place in reserve.
  • Some species of arthropods wrap leaves with cobwebs, stretch out a long thread, pull it to divert the attention of predators from their shelter. They make a puppet, which is then skillfully controlled. Some more craftsmen weave a raft from improvised means, float on the surface of the water, catch fry, larvae, and crustaceans.

The spider leaves the trapping nets with significant damage to the threads by insects. Starts forming a new canvas after 12 victims caught.

On a note!

The arthropod often eats its invention. This phenomenon is explained by the replenishment of the body with protein, the presence of moisture that accumulates on the canvas due to dew.

How a spider spins a web

Many arachnids are nocturnal, engaged in "weaving" in the dark. How long a spider weaves a web depends on the type of arthropod. On average, the orb weaver takes about 1 hour to form strong trapping nets. If reconstruction is required, the process takes a few minutes.

How quickly a spider spins a web can be seen in the video below. This arthropod does this automatically, each time repeating the same pattern. The most attractive are the openwork patterns of the orbs. Initially, a strong web is taken, stretched in the shape of a triangle, then cells of different sizes are formed.

Interesting!

The web, which lives in the rainforests of Brazil, is so strong that it is used by local fishermen to catch fish. The threads are used to weave a thin, but very durable fabric. Kraig Biocraft manufactures bulletproof vests from natural raw materials of spiders.

How a spider weaves a web between trees can be seen in the garden, in conditions wildlife. Openwork fabric or funnel sparkles in the sun, attracts insects. But the process itself, like a spider pulling a web between two trees, deserves admiration. Initially, the predator descends, waits for a gust of wind, moves through the air to a neighboring tree, and fixes the second end there. Then the matter remains small.

During the flight, the spider controls the speed by adjusting the length of the thread. When elongated, it moves slower; when contracted, it moves faster. To land, you need to throw a web on a plant, tree.

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, in spider webs a wide variety of animals are caught, ranging from insects and even small birds.

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 homes with cobwebs. 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 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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Article for the competition "bio/mol/text": The web is one of nature's amazing technological finds. The article talks about the possibilities of using the web for the production of medical dressings. The author shares his experience in improving the "productivity" of spiders and the selection of optimal conditions for their maintenance.

Note!

Editorial

Biomolecule highly values ​​curiosity and interest in invention. For the second time in the bio/mol/text competition, inventor Yuri Shevnin shares his ideas and findings with the audience of our portal. The editors are impressed by the author's creative approach and the desire to share knowledge with others, however, it must be borne in mind that this article is not strict scientific research, and the new medical dressings described in it still need to be tested for the possibility of using in clinical practice.

The sponsor of the nomination Best Article on the Mechanisms of Aging and Longevity” is the Science for Life Extension Foundation. The Audience Choice Award was sponsored by Helicon.

Contest sponsors: 3D Bioprinting Solutions Laboratory for Biotechnology Research and Visual Science Studio for Scientific Graphics, Animation and Modeling.

I entered the next room, where the walls and ceiling were completely covered with cobwebs, except for a narrow passage for the inventor. As soon as I appeared at the door, the latter shouted loudly so that I would be more careful and not break his webs. He began to complain about fatal mistake which the world has hitherto done, using the work of silkworms, while we always have a multitude of insects at hand, infinitely superior to the worms mentioned, for they are endowed not only with the qualities of spinners, but also of weavers. The inventor further pointed out that the disposal of spiders would completely eliminate the expense of dyeing fabrics, and I was quite convinced of this when he showed us a lot of beautiful multi-colored flies with which he fed the spiders and whose color, according to him, must necessarily be transferred to the yarn made by the spider. And since he had flies of all colors, he hoped to satisfy the tastes of everyone, as soon as he could find suitable food for the flies in the form of gum, oil and other sticky substances, and thus give greater density and strength to the threads of the web.

D. Swift

Gulliver's travels. Journey to Laputa (1725)

Spider web medical dressings

Due to the fact that blood donation is an expensive and limited field of medicine, scientists and physicians around the world are working to develop alternative methods for restoring damage to the human body. At the same time, the widespread occurrence of drug-resistant forms of microorganisms, the presence of toxic, allergenic and other side effects in antibiotics and chemotherapy drugs dictate the need to search for new non-toxic drugs with antimicrobial action and a stimulating effect on recovery processes. Similar properties can be endowed, for example, with anti-burn dressings and bandages. Burns are one of the most common traumatic injuries in the world. In Russia, more than 600 thousand burns are registered every year. In count deaths burns are second only to those sustained in car accidents.

The author seems promising to obtain anti-burn dressings and dressings from the web. Silk is a more accessible material, and its production already exists. However, the web, due to the special topology of molecules and the structure as a whole, has great prospects for medical dressings and matrices in scaffold technology * ( scaffold technology, from English. scaffold- scaffolding, scaffolding) - cultivation of cells on three-dimensional substrates of natural or artificial origin in order to spatial formation grown organ or its fragment (Fig. 1).

* - About some other wonderful properties of the web "Biomolecule" told earlier: " "Smart" web glue» . - Ed.

Figure 1. Web Linothele megatheloides under the microscope

According to electron microscopy, matrices of silk fibroin and recombinant spidroin (web protein) differ in pore parameters. Pore ​​walls in fibroin matrices have a more uniform structure with a scaly rough surface, while spidroin matrices have a looser structure with a perforated surface. The internal nanoporous structure of the recombinant spidroin matrix explains its ability to form a more favorable microenvironment for tissue regeneration in the body. The interconnectedness of structures is necessary condition for even cell distribution and efficient tissue ingrowth in vivo, as it promotes active gas exchange, nutrient delivery and proper metabolism.

About it amazing property webs have been known for a long time. IN folk medicine there is such a recipe: to stop the blood, you can attach a web to a wound or abrasion, carefully cleaning it from stuck insects and small twigs.

The web has a hemostatic effect and accelerates the healing of damaged skin. Surgeons and transplantologists could use it as a material for suturing and reinforcing implants, as well as a framework for growing artificial organs. For example, if a mesh frame made of cobwebs is impregnated with a solution of stem cells, they will quickly take root on it, vessels and nerves will stretch to the cells. The web itself will eventually dissolve without a trace. With the help of the web, it is possible to significantly improve the properties of many materials that are currently used in medicine. For example, the web has an electrostatic charge that helps spiders attract prey. This charge of the web can also be used as part of medical dressings. The web is negatively charged, and the damaged part of the body is positively charged. Thus, when the wound interacts with the web, an electrical balance is established, which has a positive effect on the healing process. Bandages with cobwebs, due to electrostatic interaction with the wound, draw out microorganisms from it and keep them inside the bandage itself, preventing them from multiplying.

The composition of the web includes three substances that contribute to its durability: pyrrolidine, potassium hydrogen phosphate And potassium nitrate. Pyrrolidine strongly absorbs water; this substance prevents the cobwebs from drying out. Potassium hydrogen phosphate makes the web acidic and prevents fungal and bacterial growth. Low pH causes proteins to denature (make them insoluble). Potassium nitrate inhibits the growth of bacteria and fungi.

A cobweb bandage provides an outflow of wound exudate and microorganisms from the wound surface, inhibits pathogenic microflora, and has anti-edematous and anti-inflammatory effects. Impregnated with an anesthetic, it will also anesthetize, creating optimal conditions for the healing process to take place.

History of web production

The main problem for the widespread use of products containing the web is the difficulty of obtaining it on an industrial scale. For hundreds of years in Europe, people have tried to build spider silk farms. In March 1665, the meadows and fences near the German Merseburg were covered with an incredible amount of webs of some kind of spiders, and from it the women of the surrounding villages made ribbons and other decorations for themselves.

In 1709, the French government asked the naturalist René Antoine de Réaumur to find a replacement for Chinese silk and try to use the web to make clothes. He collected a web of spider cocoons and tried to make gloves and stockings, but after a while he abandoned this venture due to lack of material even in order to produce one pair of gloves. He calculated that it would take 522-663 spiders to process one pound of spider silk. And for industrial production it would take hordes of spiders and clouds of flies to feed them - more than flies over all of France. “However,” Reaumur wrote, “perhaps in time it will be possible to find spiders that give more silk than those that are usually found in our state.”

Such spiders were found - they were spiders of the genus Nephila. Recently, a cape weighing more than a kilogram was woven from their web. Where these wonderful spiders live - in Brazil and Madagascar - locals use the web to make yarn, scarves, capes and nets, collecting from bushes or unwinding egg cocoons. Sometimes the thread is pulled directly from the spider, which is put in a box - only the tip of its abdomen with spider webs sticks out of it. From the warts and pull the threads of the web.

Using different methods and from different spiders, experimenters obtained, for example, threads of this length: 1) in two hours from 22 spiders - five kilometers, 2) in a few hours from one spider - 450 and 675 meters, 3) in nine "unwindings" of one spider within 27 days - 3060 meters. Abbé Camboué explored the possibilities of the Madagascar spider Goleba punctata: he improved his business so much that he “connected” living spiders in small drawers directly to a special type of loom. The loom pulled threads from spiders and immediately weaved the finest fabric from them. Spiders Goleba punctata they tried to acclimatize in France and in Russia, but nothing came of it. In a wide production web Nephila hardly ever do: for content Nephila or crosses need special farms, although in summer they can be kept on a loggia or balcony. To solve this centuries-old problem, a modern integrated approach and the creation of optimal conditions for spiders and insects, as close as possible to natural ones, are required.

Web production today

In the 20th century, with the advent of chemical pesticides and synthetic fabrics, beneficial insects and spiders were forgotten. However, pesticides alone have not solved the problem of crop pests. A conservation strategy has been developed biodiversity which provides for the integration of beneficial insects and spiders into the crop system for natural pest control.

Today, creating new jobs in Russia requires a new strategy to reduce monoculture crops and the construction of mini-farms not only for growing vertebrates, but also for growing spiders and insects.

This can be done in cities as well. Usage problem organic waste cities today is particularly acute. This waste can be used to feed insects. In the cities there are only small farms for growing crickets, cockroaches and zofobas. Spiders are bred by only a few enthusiastic keepers. At the same time, basements and attics, where these animals mainly live, are not used in any way for the disposal of organic waste and for the cultivation of insect and spider larvae.

The aims of the new agricultural strategy are to farm ecologically, increase biodiversity and generate income from the construction and operation of small family farms for breeding insects and spiders. These organisms, their venom and webs can also be sold for export.

It is impossible to synthesize the web chemically - the structure of proteins is too complex. All the leading firms in the world have abandoned attempts to synthesize the web. Several laboratories continue to work and try to get the web from yeast, bacteria and even goats. All these approaches require very sophisticated equipment and high financial costs. At the same time, their threads turn out to be of a completely different quality, inferior to the “original” in terms of strength and antibacterial properties. In addition, the amount of web produced in such laboratories is very modest: scientists are sometimes shown on TV demonstrating samples of synthetic web the size of a fingernail in tweezers or in a small vial.

Live spiders were also abandoned to collect the web, although this idea was proposed repeatedly. There were several obstacles. First of all, the quarrelsomeness of spiders and the tendency to cannibalism interfere: when kept together, these animals are at enmity and eat each other. In addition, most spiders produce very little web: it is estimated that 27,000 medium-sized spiders would be required to produce 500 grams of web; according to G.P. Kirsanov, cross-spiders produced 230 mg of cobwebs in 24 hours. Fourteen thousand spiders of the genus Nephila give approximately 28 g of cobwebs. According to other sources, about 23 thousand spiders are required to obtain 29 g of cobwebs. This difference in numbers suggests that spider performance data needs to be confirmed. It is not known what kind of spiders and "medium size" developed a web for weighing in one case or another.

The first obstacle to spider breeding described can and should be turned into a boon: the tendency of spiders to cannibalism encourages the creation of containers for them isolated from each other, thereby preventing both epidemics and mass mortality. At the same time, for the manufacture of medical materials and medicines from the web, it is necessary to use non-spiders of the genus Nephila or crosses, and spiders with the largest arachnoid appendages themselves - Linothele megatheloides(Fig. 2) and others Dipluridae.

Figure 2. Spider Linothele megatheloides, female.

As a result of the study, the author obtained data that spiders of the species Linothele megatheloides per month produce more than 2 g of cobwebs. They have long (more than 20 mm) arachnoid appendages for this (Fig. 3). These organs have more than a thousand microfilaments through which the web threads exit like a film.

The author tested the web to create anti-burn dressings (Fig. 4). As a result of using this web on a burn, healing occurred within a week. It did not require additional dressings and removal of pus. Two weeks later, there was not even a trace of a burn left.

Figure 3. Spider appendages Linothele megatheloides under a microscope.

Figure 4. Burn covered with a bandage with cobwebs Linothele megatheloides.

Planted in a special container Linothele megatheloides an hour later they begin their work and layer by layer cover the textile substrate of a container with an area of ​​1 m 2 with cobwebs. In two months, the web from one spider will be enough to cover the entire surface of the human body. Such an innovative medical material with cobwebs could possibly save the life of a person with burns over 60% of the entire body surface.

As a result of his observations, the author found that, thanks to special nutritional supplements, the offspring and survival of offspring Linothele megatheloides are 100%. This is an average of 50 young individuals - potential producers of "second skin" - for six months. It takes 2-3 cockroaches per week to feed one female. Spider conditions are the absence sunlight, high humidity (80-90%), temperature 28 ° C, complex nutrition and drip spraying of the web once a week. When creating favorable conditions for feeding, keeping, caring for and "milking" spiders, it is possible to achieve an increase in web spinning by 2–3 times.

Making dressings and bandages from cobwebs Linothele megatheloides

A knitted mesh base (for example, gauze with a moisture content of more than 80%) is placed on the bottom of a polyethylene container. The container has perforations for ventilation, humidity and temperature sensors, a lifting lid, a capillary nozzle and a valve for supplying live food. Containers are arranged vertically, forming a block 1.5-2 meters high (Fig. 5).

Figure 5. Dwelling Linothele megatheloides. A - Spider in a container with a knitted base. b - Scheme of the container. V - Block of containers.

Figure 6. Bandage with cobwebs Linothele megatheloides (A) and sterile packaging for it ( b).

Once a month, the container is opened, the spider is placed in another small polyethylene container, the remains of food are removed, the textile substrate with cobwebs is sprayed with a solution of hyaluronic and pantothenic acids, anesthetic and antiseptic, covered with a polyethylene stretch film and twisted. Then the roll, together with the web, is cut into 10 parts and placed in a sealed package (Fig. 6). Packed rolls are sent for radiation sterilization. The spider is released back into a large container.

Such a bandage is applied by unwinding and removing the polyethylene layer, with a cobweb on a wound or burn. When the web and textile backing are saturated with lymph, the backing is removed and only a healing and breathable web layer remains on the wound.

After a person heals his wound with a plaster with cobwebs, he will never again kill these wonderful animals.

Increased web production

Figure 7. Spider farm design Linothele megatheloides.

In order to increase the production of cobwebs and exclude diseases of live food (cockroaches and crickets), insects receive a nutritional supplement in the form of a nutrient medium - an additional source of protein and vitamins containing mycelial biomass of penicillin and streptomycin production waste, as well as deyeasted stillage - from brewer's yeast production waste . The nutrient medium is stored for up to two years at a temperature of +5 °C. To feed insects, finely chopped carrots and cabbage are thrown into chopped culture medium. On such food, cockroaches and crickets do not get sick, they grow and multiply quickly. Spiders at the same time increase the production of webs by 60%. The use of mycelial nutrition allows you to stimulate the reproduction of spiders and get the web in the maximum possible quantities. Search work food additives to increase the diversity of spider food will be continued. To create a farm for collecting cobwebs, a design project is proposed in the form of a round tent with a diameter of 12 m with a tensile coating, similar to the work of a cobweb (Fig. 7).

With the development of this eco-friendly way of creating medical dressings and bandages, experiments are possible to breed more productive hybrids of spiders of the family Dipluridae. Intraspecific hybridization, selection and special nutrition in comfortable conditions do not exclude genetic experiments to increase the size of spiders. So far, no one is doing this, and in the society of individual spider breeders, this topic is taboo.

It is possible to produce milk with the help of fungi and bacteria - but why, when there are cows? The web is much more complex in structure than the protein structure of milk. Therefore, all searches for synthetic analogues of the web can be delayed for the duration of the evolution of spiders. New species obtained by genetic modification and breeding work with the family Dipluridae will increase the size of spiders and their web productivity for the production of clothing. The web can be processed with silicone and fabric for outerwear can be obtained with unique properties. Such a fabric will cost no more than silk.

Conclusion

Described research creates the basis for a new type of animal husbandry. On this basis, it is possible to scale the production of the web at a low cost, and therefore commercialize it. The market demand for bioresorbable wound dressings is 400 thousand dm 2 /year. The predicted market capacity in this segment is $150 million.

The project can be scaled up both by increasing production and by creating mini-farms for the production of cobwebs. No complicated equipment high temperatures, high pressure and toxic materials are not required for this technology option. Currently, for example, about 5 thousand farms and 300 thousand amateur beekeepers, farmers and individual entrepreneurs are engaged in beekeeping. Not everyone can use honey, but medical dressings or cobweb plasters will be useful to everyone. While the technology is being developed and certified, everyone can be invited to grow spiders and collect webs themselves. For sterilization, you can use an ultraviolet lamp. To provide two square meters cobwebs, you will need one container with a female Linothele megatheloides and two months. Female Linothele megatheloides lives 10 years. On garden plot you can put an insulated spider house measuring 3 by 6 meters with two rooms (Fig. 8). In one, you can harvest raw materials, and in the other, you can make threads from cobwebs, weave linen and sew clothes. There is simply no waste from such a mini-factory.

Figure 8. Mini farm growing Linothele megatheloides, collecting their webs and making clothes in the garden.

Souvenirs and jewelry can be made from old shells dropped by the spider during molting by filling them with polymer resin. Poison can be extracted from the heads of dead spiders to produce medicinal preparations*. The injured and the sick will receive a new medicine - natural "skin" - and everyone will be able to create such a mini-production.

The author is not going to receive patents and certificates on the topic of research, as he wants this knowledge to be available to everyone.

* - And these drugs (in particular, analgesics) can be a great variety - despite singular the words "poison": the venom of one spider can contain hundreds of toxic components of completely different chemical nature. About libraries of spider toxins tells the article " The great strategist never dreamed» . - Ed.

Literature

  1. "Smart" web glue;
  2. Agapova O.I., Efimov A.E., Moisenovich M.M., Bogush V.G., Agapov I.I. (2015). Comparative analysis of the three-dimensional nanostructure of porous biodegradable matrices from recombinant spidroin and silk fibroin for regenerative medicine. The Madagascarians created the largest spider silk canvas. Membrane website;
  3. A cape made from spider silk will be on display in Europe. Site GlobalScience.ru, 2012;
  4. Technological platform "Medicine of the future". Website of the Eurasian Economic Commission, 2012;
  5. Aksenova L. (2013). Spiders will help you forget about pain. Website "Gazeta.ru";

Anyone can easily brush away the cobwebs hanging between the branches of a tree or under the ceiling in the far corner of the room. But few people know that if the web had a diameter of 1 mm, then it could withstand a load of approximately 200 kg. Steel wire of the same diameter can withstand significantly less: 30–100 kg, depending on the type of steel. Why does the web have such exceptional properties?

Some spiders spin up to seven types of thread, each with its own purpose. Threads can be used not only for catching prey, but also for building cocoons and parachuting (flying up in the wind, spiders can escape from a sudden threat, and young spiders settle in new territories in this way). Each type of web is produced by special glands.

The web used for catching prey consists of several types of threads (Fig. 1): frame, radial, trapping and auxiliary. The greatest interest of scientists is the carcass thread: it has both high strength and high elasticity - it is this combination of properties that is unique. Ultimate stress at break of the skeleton thread of the spider Araneus diadematus is 1.1–2.7. For comparison: the tensile strength of steel is 0.4–1.5 GPa, and that of a human hair is 0.25 GPa. At the same time, the carcass thread is capable of stretching by 30–35%, and most metals can withstand deformation no more than 10–20%.

Imagine a flying insect that hits a stretched web. In this case, the web thread must stretch so that the kinetic energy of the flying insect turns into heat. If the web stored the received energy in the form of elastic deformation energy, then the insect would bounce off the web like from a trampoline. An important property of the web is that it releases a very large amount of heat during rapid stretching and subsequent contraction: the energy released per unit volume is more than 150 MJ / m 3 (steel releases - 6 MJ / m 3). This allows the web to effectively dissipate the impact energy and not stretch too much when the victim is hit. Spider webs or polymers with similar properties could be ideal materials for lightweight body armor.

In folk medicine, there is such a recipe: on a wound or abrasion, in order to stop the blood, you can attach a web, carefully cleaning it from insects and small twigs stuck in it. It turns out that the web has a hemostatic effect and accelerates the healing of damaged skin. Surgeons and transplantologists could use it as a material for suturing, reinforcing implants, and even as preparations for artificial organs. With the help of the web, it is possible to significantly improve the mechanical properties of many materials that are currently used in medicine.

So, the web is an unusual and very promising material. What molecular mechanisms are responsible for its exceptional properties?

We are accustomed to the fact that molecules are extremely small objects. However, this is not always the case: polymers are widespread around us, which have long molecules consisting of the same or similar friend on the other links. Everyone knows that genetic information living organism is written in long DNA molecules. Everyone was holding plastic bags made of long intertwined polyethylene molecules. Polymer molecules can reach huge sizes.

For example, the mass of one molecule of human DNA is about 1.9·10 12 a.m.u. (however, this is about a hundred billion times more than the mass of a water molecule), each molecule is several centimeters long, and the total length of all human DNA molecules reaches 10 11 km.

The most important class of natural polymers are proteins, they consist of units called amino acids. Different proteins perform in living organisms extremely different functions: manage chemical reactions, are used as a building material, for protection, etc.

The skeleton thread of the web consists of two proteins, which are called spidroins 1 and 2 (from the English spider- spider). Spidroins are long molecules with masses ranging from 120,000 to 720,000 amu. In different spiders, the amino acid sequences of spidroins may differ from each other, but all spidroins have common features. If you mentally stretch a long spidroin molecule into a straight line and look at the sequence of amino acids, it turns out that it consists of repeating sections similar to each other (Fig. 2). Two types of sites alternate in the molecule: relatively hydrophilic (those that are energetically beneficial in contact with water molecules) and relatively hydrophobic (those that avoid contact with water). At the ends of each molecule, there are two non-repeating hydrophilic regions, while the hydrophobic regions are made up of many repeats of an amino acid called alanine.

A long molecule (eg protein, DNA, synthetic polymer) can be represented as a crumpled tangled rope. It is not difficult to stretch it, because the loops within the molecule can be straightened out with relatively little effort. Some polymers (such as rubber) can stretch up to 500% of their initial length. So the ability of a web (a material consisting of long molecules) to deform more than metals is not surprising.

Where does the strength of the web come from?

To understand this, it is important to follow the process of thread formation. Inside the spider's gland, spidroins accumulate as a concentrated solution. When the filament is formed, this solution leaves the gland through a narrow channel, this helps the molecules to stretch and orient them along the direction of the stretch, and the corresponding chemical changes cause the molecules to stick together. Fragments of molecules, consisting of alanines, join together and form an ordered structure similar to a crystal (Fig. 3). Within such a structure, the fragments are stacked parallel to each other and linked to each other by hydrogen bonds. It is these sections, linked together, that provide the strength of the fiber. The typical size of such densely packed regions of molecules is several nanometers. The hydrophilic areas located around them turn out to be randomly folded, similar to crumpled ropes, they can straighten out and thereby provide stretching of the web.

Many composite materials, such as reinforced plastics, are built on the same principle as the carcass thread: in a relatively soft and movable matrix, which allows deformation, there are small hard areas that make the material strong. Although materials scientists have been working with such systems for a long time, human-made composites are only beginning to approach the web in their properties.

Curiously, when the web gets wet, it shrinks a lot (this phenomenon is called supercontraction). This is because water molecules penetrate the fiber and make the disordered hydrophilic regions more mobile. If the web is stretched and sagged from insects, then on a wet or rainy day it shrinks and at the same time restores its shape.

We also note interesting feature thread formation. The spider pulls the web under its own weight, but the resulting web (thread diameter approximately 1-10 microns) can usually support a mass of six times the mass of the spider itself. If, however, the weight of the spider is increased by spinning it in a centrifuge, it begins to secrete a thicker and more durable, but less rigid web.

When it comes to the use of the web, the question arises of how to get it in industrial quantities. In the world there are installations for "milking" spiders, which pull out the threads and wind them on special reels. However, this method is inefficient: in order to accumulate 500 g of web, 27 thousand medium spiders are needed. This is where bioengineering comes to the rescue. Modern technologies allow the introduction of genes encoding web proteins into various living organisms, such as bacteria or yeast. These genetically modified organisms become sources of artificial webs. Proteins obtained by genetic engineering are called recombinant. Note that usually recombinant spidroins are much smaller than natural ones, but the structure of the molecule (alternation of hydrophilic and hydrophobic regions) remains unchanged.

There is confidence that the artificial web will not be inferior to the natural one in its properties and will find its practical application as a durable and environmentally friendly material. In Russia, research on the properties of the web is jointly carried out by several scientific groups from various institutions. Obtaining recombinant web is carried out at the State Research Institute of Genetics and Selection of Industrial Microorganisms, physical and Chemical properties proteins are studied at the Department of Bioengineering Faculty of Biology Moscow State University M.V. Lomonosov, products from web proteins are formed at the Institute of Bioorganic Chemistry of the Russian Academy of Sciences, their medical applications study at the Institute of Transplantology and Artificial Organs.