How spiders weave webs: technology for creating deadly lace

What is a web

A spider in its web.

The web itself is the secret of the arachnoid glands that freeze in the air. It is produced in special arachnoid warts, thin outgrowths on the edge of the abdomen.

The spider web contains the protein fibroin, which forms fibers and makes them strong and elastic. For connection and attachment, the same matter is used, which is immersed in a special adhesive gel secreted by other glands. They also produce fiber from the anterolateral warts, which is a slightly watery material that covers the threads themselves.

Where do spider webs actually come from?

To dispel a couple of myths, let's say that:

• The spider produces its thread using glands located in the abdomen.
• She doesn’t get out of his paws like the hero of comics and films.
• Excretion is provided by special papillae located at the bottom of the abdomen.
• It comes out of the anus, the web is not a waste product.
• Its composition does not particularly depend on the spider’s diet. The main thing is that there is sufficient nutrition.
• It is difficult to assess the labor productivity of spiders, but it is reliably known that spiders can continuously weave a thread several tens of meters long
  .
• This is all experimental data; in real life, small insects do not need such huge trapping nets.
• On the other hand, one can appreciate the scale of the tragedy if one of the plots of horror films about the invasion of these huge insects comes true in real life.
• The spider does not have any threads in its abdomen; the web is produced in a semi-liquid form and it solidifies only in air.
• It's hard to believe that such a thin thread can be so strong. But it’s all about the physical characteristics and chemical composition of the material.

Children often ask seemingly simple questions, but they cannot find the answer right away. Now you can explain to your baby in simple words where the spider gets its thread and why it weaves its ingenious webs. It’s better to remain silent about the “prospects” of an invasion of giant spiders; the writers’ fiction will remain just a fiction.

How does a spider make a web?

Creating a web.

The process itself is very interesting. Production goes like this:

1. The spider presses the web warts to the substrate.
2. The secret sticks to him.
3. The spider uses its hind legs to pull out the viscous mixture.
4. As the spider moves forward, it draws out the secretion and it freezes.
5. The animal walks along the thread several times, thereby strengthening it.

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 own weight only if the spider weaves it 50 meters long.
2. Exceptional subtlety. An individual web is noticeable only when caught in a beam of light.
3. Elasticity and resilience. The thread stretches 2-4 times without breaking, and without loss of strength.

And all these qualities are achieved without any technical equipment - the spider makes do with what nature has provided it with.

Usage and Functions

Spider web fiber is very strong, comparable to the density of nylon. According to some opinions, this is because the spider creates it while hanging on the same fiber.

It has interesting features:

1. Tension. Even though the threads are compressed or stretched, they return to their usual place.
2. Articulation. An object in a web can be rotated in one direction, but it will not twist or get tangled.

It is believed that the main function of the web is to catch prey. This is true, but it has a number of other important functions.

For food

Spider food caught in the net is immobilized there. And they often wrap the prey itself in a web.

For reproduction

Males may begin the act of courting a female by tugging at her web, thus attracting her attention. Some species leave seminal fluid on the web to fertilize the female.

For posterity

The eggs also develop in a cocoon of spider webs. Young animals are raised there for some time.

For life

Water spiders make cocoons underwater, leaving air in them for breathing. Those who build holes weave it around the inside of the home.

For guard

Some species weave leaves into the web, which act as puppets. Spiders move them when predators approach in order to deceive them.

Why can't you kill spiders?

There are a huge number of superstitions about spiders and their webs. In most cases, killing this insect or destroying its house is considered a bad sign. There is a reason for this:

• The spider feeds on other insects, killing flies, mosquitoes and other uninvited guests.
• One such resident with 8 paws, settling in your house, will work better than a squad of exterminators. And he won’t ask for anything for his work.
• Once all the insects are destroyed, the spider will have no options for food and will be forced to leave your home.

But there are always disadvantages:

1. The web collects all the dust and dirt.
2. Living in the southern regions, you may encounter poisonous and life-threatening species of spiders.
3. No one has canceled arachnophobia; the fear of spiders will make you instantly forget about all their usefulness.

Therefore, decide for yourself exactly how to deal with the uninvited guest. If you kill all other insects without hesitation, there is no point in making any concessions for the owner of eight legs.

On the other hand, pity for harmless creatures should always be present, at least at some level.

Types of web

Depending on the type of spider, the shape of the finished web structure differs. This can be said to be a distinctive feature.

Usually there are 3-4 load-bearing threads, which are the basis of the structure and are attached to the base with connecting disks. Radial ones converge towards the center, and spiral ones create shape.

It’s curious, but the spider itself is not attached to its web and does not stick. It only touches the nets with the tips of its feet, and there is a special lubricant on them.

Round form

Round web.

This beautiful lightweight lace is a deadly weapon. The spider first makes a frame, then places radial fibers towards the center, and at the end the spiral threads are laid.

The prey falls into such a trap, and the hunter senses movement and gets out of the ambush. If a hole appears in the web, the spider completely weaves a new one.

Strong web

This is a design of a round or similar shape with a large diameter. A net with a large number of meshes is prepared to catch large prey. There is a hammock - a structure in which spiders settle and wait for their prey. It is flat, located like a horizontal mattress, from which vertical threads extend along the edges for fastening.

Variety of web.

The structure and composition of the web

Having a general idea of ​​why spiders weave webs, you can try to figure out what this interweaving of threads is

:

1. It consists of many single threads.
2. All of them are attached to a solid surface at least at one point.
3. They go in the same plane, but in different directions.
4. Initially, the spider weaves long threads, forming a kind of frame.
5. Then he interweaves them with longitudinal threads in a circle, completing the work.
6. How sticky the web will be depends on how long it has been in existence and the type of spider.
7. The insect itself must be extremely careful, because, like its prey, it is not immune from the possibility of falling into its own trap.
8. The web is only a temporary home; if environmental conditions change or competition increases, the spider, without hesitation, will move to another place and begin to weave a new web.

But any construction requires material

.
the spider thread
in its properties :

• Mainly consists of proteins.
• Its properties are most similar to nylon.
• Has a huge margin of tensile strength. Up to two hundred kilograms per 1 square millimeter.
• If humanity learned to synthesize this kind of tissue, it would be used in many advanced branches of science and production.

Types of spiders, names and photographs

Scientists have described more than 42,000 species of spiders. About 2,900 varieties are known in the CIS countries. Let's consider several varieties:

• Blue-green tarantula (
  Chromatopelma cyaneopubescens )

one of the most spectacular and beautifully colored spiders. The tarantula's abdomen is red-orange, its limbs are bright blue, and its carapace is green. The size of the tarantula is 6-7 cm, with a leg span of up to 15 cm. The spider’s homeland is Venezuela, but this spider is found in Asian countries and on the African continent. Despite belonging to tarantulas, this type of spider does not bite, but only throws special hairs located on the abdomen, and only in case of severe danger. The hairs are not dangerous for humans, but they cause minor burns on the skin, similar in effect to nettle burns. Surprisingly, female chromatopelma are long-lived compared to males: the lifespan of a female spider is 10-12 years, while males live only 2-3 years.

• Flower spider (
  Misumena vatia )

belongs to the family of side-walking spiders (Thomisidae). Color varies from completely white to bright lemon, pink or greenish. Male spiders are small, 4-5 mm long, females reach sizes of 1-1.2 cm. The species of flower spiders is distributed throughout European territory (excluding Iceland), and is found in the USA, Japan, and Alaska. The spider lives in open areas with an abundance of flowering herbs, as it feeds on the juices of those caught in its “embraces” and.

• Grammostola pulchra (
  Grammostola pulchra )

Sidewalk spiders (crab spiders) spend most of their lives sitting on flowers waiting for prey, although some members of the family can be found on tree bark or forest floors.

Representatives of the family of funnel-web spiders place their webs on tall grass and bush branches.

Wolf spiders prefer damp, grassy meadows and swampy wooded areas, where they are found in abundance among fallen leaves.

The water (silver) spider builds a nest underwater, attaching it to various bottom objects with the help of webs. He fills his nest with oxygen and uses it as a diving bell.

Spider farms

Getting threads

First of all, a study was conducted to determine the length of the arachnoid thread that can be obtained from the spider Araneus marmoreus (Fig. 5) by unwinding the web from arachnoid warts [10].

Figure 5. Spider A. marmoreus

Exhaustion was carried out in two versions.
In the first version, the web was pulled out of the spider to the limit, that is, until the spider completely stopped secreting the web. Such extreme exhaustion led to rapid depletion of the arachnoid glands after one or two operations. After such an experiment, the spiders continued to live and eat food, but the activity of the web apparatus ceased. We present a table of the maximum exhaustion of six Araneus marmoreus females, which is presented in [10]. Table. Extreme exhaustion of Araneus marmoreus females . Source: [10].

In the second option, no more than 100–150 m of web from each female was removed daily, after which the removal was stopped.

The productivity of spiders during portioned exhaustion increased significantly. With extreme exhaustion, an average of 263 m was obtained from one female, and a maximum of 524 m. With portioned exhaustion, the average figure increased almost three times, reaching 739 m, and the maximum reached 1000 m.

It is noteworthy that the systematic activity of the arachnoid glands, with proper nutrition, helps to increase production. The author of the work compared the portioned exhaustion of spiders with the milking of cows used in agricultural practice, where a systematic increase in the activity of the glands leads to a multiple increase in production.

What is it for?

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

• for insulating minks before wintering;
• to create cocoons in which offspring mature;
• for protection from rain - spiders use it to make a kind of canopy that prevents water from entering the “house”;
• for traveling. Some spiders migrate on their own and send children away from the family on long webs blown by the wind.

Curious facts

The web has not yet been fully studied by scientists. And modern science is not yet able to repeat this natural phenomenon.

1. The spider's web is simply amazingly strong. If you weave a net the size of a football field from such threads, it will be able to stop a flying Boeing. In South America, there are spider bridges on which monkeys cross gorges and use spider nets to catch fish.
2. Spider "lace" has electrostatic properties, which allows its threads to rush towards prey flying by.
3. Many spiders eat their old webs.
4. Spider web is considered to be almost the lightest material in the world: if stretched along the entire equator, it would weigh only 340 grams.

Surely each of you has paid attention to the sophisticated, delicate, silky “handkerchiefs” that spiders hang on trees and grass in the sunny summer. When silvery dewdrops glisten on openwork spider yarn - the sight, you see, is incredibly beautiful and bewitching

But several questions arise: “where is the web formed and how is it used by the spider”, “where does it come from and what does it consist of”. Today we will try to figure out why this animal decorates everything around with its “embroidery.”

What do spiders eat?

• Spiders usually include insects as the basis of their diet. Small arachnids happily eat crickets, flies, mealworms, mosquitoes, butterflies, cockroaches and grasshoppers.
• Huge tropical tarantula spiders happily feed on small frogs, lizards, other spiders, mice, bats, and small birds.
• Varieties of water spiders obtain food for themselves from the water, catching tadpoles, midges or small fish floating on the water surface.
• There are interesting facts that the weight of food that all spiders eat throughout the year is greater than the mass of the population that currently lives on Earth.

Cross spider: description

The cross spider represents the order of spiders and is part of the suborder of araneomorphic spiders, as well as the genus of cross spiders.

To date, scientists do not have information that would accurately reflect the period of appearance of this species on Earth. Therefore, they operate mainly with approximate data. The fact is that the chitinous shell of spiders does not last long. Several remains of these creatures were discovered in fragments of hardened resin, as well as in amber. Experts are inclined to believe that arachnids appeared on our Planet about 210 million years ago. The representatives of the emerging detachment were not large in size, since their body sizes did not exceed 0.5 centimeters.

The newly appeared inhabitants of our Planet also differed in the structure of their bodies. The ancestors of modern spiders had a tail, with which the animals weaved strong webs. In those days, spiders used their webs to line burrows and also to protect egg clutches from external factors. As evolutionary development progressed, such a part of the body turned out to be unnecessary, and the tail disappeared. Modern spiders have a completely different spinning apparatus, which appeared in them some time after the loss of their tail.

It is assumed that the first arachnids appeared on Gondwana, after which they began to spread throughout the Earth at a fairly rapid pace. The coming ice ages significantly narrowed their habitat areas. Spiders are characterized by fairly rapid adaptation to various living conditions, depending on the species.

Spider is a cross. Class Arachnida. Biology Lessons Online

Appearance

Arachnids are characterized by the fact that their body consists of two parts - the cephalothorax and abdomen. In addition, spiders have special arachnoid warts, as well as a walking apparatus represented by hips, knee joints, shins, forearms, paws and claws. In addition, spiders are armed with chelicerae and pedipalps.

The cross spider does not have a large body size. This species has well-defined dimorphism, since males have significantly smaller body sizes compared to females. Females grow up to 4 and a half centimeters in length, while the body length of males does not reach one and a half centimeters.

A sand-colored chitinous shell covers the entire body of the arthropod. As a rule, it is reset every time the spiders molt.

Spiders have 12 limbs:

• A pair of chelicerae is designed to hold and kill prey.
• 4 pairs of legs for movement. Each paw has a claw.
• A pair of pedipalps with which the spider fixes its prey. In addition, with their help, the male fertilizes the female, transferring his seminal fluid into the female’s seminal receptacle. Seminal fluid is located in reservoirs located on the last segments of the pedipalps.

Cross spiders have 4 pairs of eyes, although they are rather poorly developed, so spiders can only see silhouettes. Spiders navigate in space due to their well-developed sense of touch. The hairs that cover the entire body of the arthropod serve as sensors.

Important point! Each hair on the spider's body performs its role. One type of hair is responsible for light, another type for sounds, a third type for movement, etc.

The spider's abdomen is round in shape, but it is solid, without division into segments. A pattern in the form of a cross is clearly visible on the back of the spider. In the lower part of the abdomen there are 3 pairs of warts, which secrete a secretion for the construction of the web.

The respiratory system of the cross spider is represented by two pulmonary sacs located on the abdomen, as well as a tracheal tube. The heart is located closer to the back area. The heart has an original shape, in the form of a tube from which blood vessels diverge.

Habitat

Cross spiders are found almost throughout the Euro-Asian continent, as well as in North America.

Their favorite habitats are high humidity, low light and high ambient temperatures. They prefer forest edges, meadows, gardens, fields, etc. Human housing is no exception, where spiders settle in various crevices, joints between walls, spaces between walls and furniture, as well as in other hard-to-reach places. These spiders are often found on various vegetation near bodies of water.

Cross spiders live:

• On the territory of Europe.
• On the territory of our country.
• In Africa.
• In Asia.
• In North America.

As a rule, for their life activities, spiders choose places where it is easy to weave a hunting web, which will catch a sufficient number of insects. These spiders can be found without problems in the city, namely in parks, squares, etc.

What does it eat?

Cross spiders are a poisonous species of spider, so this creature should not be considered completely harmless. Shows its main activity at night.

The sources of food are:

• Flies.
• Mosquitoes.
• Butterflies.
• Nasty.
• Aphids, etc.

The spider comes out of its hiding place and positions itself in the center of its web, while it freezes without making any movements. When potential prey gets into the web, the spider reacts with lightning speed and immediately plunges its front pair of limbs into it, and also injects poison. As a result, the victim is paralyzed and unable to resist. If the spider is hungry, it will eat the food item right there, but it can also leave it “for later.”

Cross spiders are quite voracious and within a day they eat living creatures that weigh more than the weight of the spider itself. That is why spiders, even when in their shelters during the day, do not lose contact with the hunting web, which at one end is connected to one of the spider’s limbs.

Interesting moment! Not all food objects that fall into a spider's web can serve as food for it. Spiders do not eat poisonous or bad-smelling insects. The same applies to prey that is too large for the spider to handle. In this case, the spider frees the “prisoners” by biting through the holding threads of the web.

Arthropods have an external type of digestive tract, so they are not able to digest food on their own. Digestion of food occurs due to the action of injected poison. Under the influence of toxins, the insides of the victim turn into a liquid substance, which the spiders simply drink. You can observe this process by seeing that the spider wraps its prey in a cocoon, where its preliminary digestion occurs.

Cross spider against a large bug

Character and lifestyle

As a rule, spiders are nocturnal hunters who tend to look for food for themselves almost around the clock, despite the fact that during the daytime spiders mostly rest. They try to settle in places where there is little light but enough moisture.

In order for a spider to weave a web, there must be some kind of support nearby, in the form of green vegetation, as well as natural or artificial structures. After the web has formed, the spider may be on or near the web, hiding in a secluded place. As a rule, the web is quite strong and can support fairly large prey, the size of which exceeds the size of the spider itself.

Cross spiders are busy weaving their hunting webs, as they often become unusable. In addition, the trapping network of the cross spider is characterized by considerable size and must be constantly restored.

Interesting to know! The spider cannot become entangled in its web, since it moves through areas that do not have such a feature as stickiness.

Spiders prefer to go hunting at night, since the bulk of their natural enemies hunt in the daytime. At the same time, when it is dark, spiders begin weaving or repairing webs. It’s hard to even believe that spiders are capable of forming a web so accurately and meticulously. Looking at this creation of nature, one would like to say that a real talented master is capable of this. And this despite the fact that the spider has poor eyesight. As a rule, cross spiders prefer to lead a solitary lifestyle.

Reproduction and offspring

From spring until autumn, spiders are busy weaving webs to provide themselves with food. Before the onset of the mating season, males leave their shelters and go in search of their other “half” in order to recreate their own kind. Most likely, the size of the males is associated with this type of behavior. During the mating season, they eat practically nothing.

Cross spiders are dioecious arthropods. Mating dances also occur at night and involve the males clattering their limbs. The transfer of seminal fluid occurs at the moment when the male manages to reach the female’s head with his limbs. After this complex mating process, many males die in the clutches of the female.

This period begins with the onset of autumn. The female, after mating, forms a cocoon from the web in which she places the eggs. The number of eggs can range from 3 to 7 hundred pieces. The female carries it around for some time until she finds a suitable place to hide it securely. Future offspring, being in such a cocoon, are reliably protected from external natural factors. With the arrival of spring, small spiders begin to emerge from the eggs and remain in the cocoon for some time. After some time, the spiders leave the cocoon, crawling in different directions. At this moment, small cross spiders become completely independent and are ready to lead an isolated lifestyle.

When leaving the cocoon, spiders try to do so as quickly as possible, otherwise they can serve as a source of food for older individuals. The faster they do this, the greater their chances of survival.

Interesting to know! As a rule, small spiders, in order to have a better chance of survival, use webs, covering vast distances with its help.

These spiders easily adapt to new living conditions. Thanks to this feature, many exotic lovers often keep cross spiders at home. To do this, you will have to acquire a terrarium large enough to accommodate the web.

Natural enemies

Cross spiders have more than enough natural enemies, despite the fact that they are considered poisonous. To increase their chances of survival, spiders prefer to be nocturnal. The main enemies of this type of spider include birds, as well as parasitic insects. Some of the parasitic insects are waiting for the moment when the spider appears on its web and freezes in anticipation of the next food item. At this moment, they quickly lay their eggs on the spider’s body.

After some time, larvae emerge from the eggs and begin to feed on the spider’s flesh. These spiders are not impressive in size, so they can become lunch for a larger spider. Some amphibians, in the form of frogs or lizards, can snack on spiders.

Being in natural conditions, the main enemies of spiders are:

• Salamanders.
• Geckos.
• Iguanas.
• Frogs.
• Jerzy.
• The bats.
• Ants.

Humans cannot be considered one of the natural enemies of the spider, but the spider itself can harm human health. Naturally, the spider is unlikely to attack first, but in case of serious danger, the spider may bite. The bite cannot be fatal, but discomfort for the entire body is guaranteed.

As a result of a spider bite, a person experiences severe pain at the site of the bite, dizziness, nausea, vomiting, swelling at the site of the bite and suppuration. Basically, these symptoms disappear without the use of medications.

Competition “Bio/Mol/Text”-2020/2021

This work was published in the “School” category of the “Bio/Mol/Text” competition - 2020/2021.

The partners of the nomination are the Vita Medical and Biological School and the New School.

The general partner of the competition is the annual biotechnology conference BiotechClub, organized by the international innovative biotechnology company BIOCAD.

The sponsor of the competition is SkyGen: a leading distributor of life science products on the Russian market.

Competition sponsor: the largest supplier of equipment, reagents and consumables for biological research and production.

They caught three hairy spiders in the bushes and... made them work. One spider was weaving a net for fishing from its web. The second spider wove clothes from its web. N. Sladkov. Planet of Wonders

In the last century, humanity has experienced more than one technological revolution. These revolutions changed our lives. Inventions such as cars, airplanes, televisions, lasers, computers and the Internet have accustomed us to change. History has shown that we cannot stand still. Technogenic revolutions have also affected the production of new materials for various spheres of our life. From heavy machinery and hard metals, humanity is moving towards biotechnology and biomaterials. One of these promising materials is spider web - an amazing material that combines the strength of steel, the rigidity of Kevlar and lightness. cobwebs. It also turned out that spider webs can be effectively used in various medical bioconstructions, since spider web material is biologically compatible with the human body [1].

Biomolecule previously spoke about some of the properties of “spider web glue” and the possibilities of its use: ““Smart glue” from spider webs” [3].

But for the industrial use of any material, it is important to solve at least two problems: how to obtain the material in sufficient quantity and how much it will cost. Silkworm silk has had no competitor in the form of artificial or synthetic material for 4,500 years. In our age of technical revolutions, spider silk, having not yet found widespread use in its native form, already has serious synthetic rivals. Will he even be able to withstand such competition?

In this article, we'll look at how humans have tried to adapt spiders to life in captivity over the centuries, and try to understand whether spiders can be tamed and made to work for us.

Spider in the house. Folk signs.

You should not be upset if a spider appears in the house, because according to many folk signs, this indicates reigning harmony and peace. A cobweb over the bed portends imminent and inevitable happiness.

In ancient Russian mythology, spiders are in the house

- these are none other than brownie dogs. And the more wards he has, the more powerful the protection of your home.

Seeing a spider sitting on a web, make a wish and say the magic words: “If eight legs begin to go down, then my wish will come true.” And watch the spider's movement.

The only places where there should be no cobwebs in the house are the kitchen and the door. The presence of a cobweb in the kitchen means a lack of love in the house, and seeing it above the door for a girl means betrayal of a loved one. At the same time, under no circumstances should you remove the cobwebs - this will make the situation even worse.

In general, a spider in a house, according to popular belief, symbolizes the prosperity of the owners and, if you still need to get rid of it, carefully place it on a dustpan and take it outside.