A spider is not an insect because... Spider is an insect or animal

Studying wildlife- the structure, origin and genetics of organisms, scientists draw up a huge diagram. They systematize the data received. Scientists have introduced a number of taxa. The most basic of them are: kingdom, class, order, family, genus and species. The science of taxonomy performs great job. It is often necessary to make changes to the system as scientists discover something new.

Is a spider an insect or not, and why?

Looking at the system of the living world, we can see that historically there have been 5 kingdoms: animals, plants, fungi, bacteria and viruses. Spiders belong to the animal kingdom. An interesting question: is a spider an insect or an animal that does not belong to the same class?

Common signs of insects and spiders

Insects and spiders belong to the same phylum of arthropods. Arthropods have the following external signs:

The body is divided into sections.
The limbs are articulated and are the main organs of movement. They are movably connected to each other. Animals are capable of a variety of movements.
The chitinous cover protects the body of the arthropod; it also covers the limbs. Protects against mechanical damage, does not allow water to pass through (prevents evaporation in terrestrial arthropods, prevents water from entering the body - in aquatic organisms), and also serves as an exoskeleton (muscles are attached to it).
Presence of shedding. Due to the fact that the chitinous cover does not stretch.

What class do spiders belong to?

The answer to the question: “Is a spider an insect?” taxonomy gives. What class do spiders belong to? Is a spider an insect or not?

Despite the presence common features, spiders and insects were previously classified as different classes: arachnids (Arachnida) and insects (Insecta). In modern taxonomy, two classes of insects have been identified: cryptomaxillary and open-jawed, combined into one superclass - six-legged (Hexapoda). The class Arachnida stands apart. Is a spider an insect? The answer is no. However, how is it different from insects?

Signs of insects

The insect's body is divided into head, thorax and abdomen. The head consists of five fused segments. There are antennas on the head with receptors for touch and smell. The eyes are compounded, that is, they consist of many simple ocelli. There are mouthparts for chewing food.

The chest includes segments: anterior, middle and posterior. Each segment carries a pair of motor limbs. In addition, the middle and hind ones each include a pair of wings: chitinized elytra and, in fact, wings. The abdomen also consists of segments, on the sides of which paired respiratory openings open.

Signs of arachnids

Signs characteristic only of arachnids show how different spiders are from insects. They answer the question: is a spider an insect or not?

The spider's body is divided into the cephalothorax and abdomen. That is, there is no jumper between the head and chest; they are fused during evolution. And in such an arachnid as the haymaker, even the cephalothorax is fused with the abdomen. Haymakers often settle in human houses. They have long legs, but they should be distinguished from the long-legged spider, whose cephalothorax and abdomen are separate.

The absence of antennae distinguishes spiders from insects. But there are chelicerae - limbs bearing claws. They serve to inject poison into the victim. The chelicerae of males are noticeably longer than those of females. Pedipalps are a sign of spiders. They look like a fifth pair of legs. However, spiders do not rely on it; they use it to capture prey.

Spiders' eyes are not compounded. They have from one to six pairs of eyes. Most often 8. However, vision is very poor. They distinguish objects at distances of up to 30 centimeters.

Spiders do not chew their prey. They have a narrow mouth opening with which they suck in already digested liquid. To do this, they first inject into the victim, in addition to poison, digestive juice. They wait for some time until the food is digested. They will suck up the finished liquid and can add digestive enzymes to it again. This method of digestion is called extraintestinal.

The cephalothorax consists of six fused segments, each bearing a pair of limbs: chelicerae, pedipalps and walking limbs. Spiders have eight legs and no wings.

The arachnoid glands are located in the lower part of the abdomen. Only spiders weave the web needed for hunting. The vast majority of spiders are predators.

The respiratory organs are not only the trachea, but also the leaf-shaped lungs. The latter are depressions in the abdomen. Their walls form many thin plates. Through them, gases diffuse into the hemolymph. The lungs open outwards with breathing holes.

Convergent traits of spiders and insects

Scientists also once decided the question of whether a spider was an insect or not. They were faced with the task of finding out the origin of some organs found in both spiders and insects.

Malpighian vessels are excretory organs that characterize both spiders and insects. However, it is believed that during evolution these organs developed independently of each other, that this is a convergent similarity. Malpighian vessels are numerous tubes. They blindly end in the body cavity of the arthropod, and exit through a hole into the intestine. Unnecessary substances are filtered into tubes from the hemolymph and released into the environment.

The presence of a tracheal respiratory system in spiders and insects is also considered convergence. Thus, the decision of convergent similarity only supported the inclusion of spiders and insects in different classes.

Schoolchildren and biology lovers ask the question: “Is a spider an insect or not?” Indeed, their small size and some similarity in structure make them similar to them. However, there are enough differences to classify spiders into a different class.

SO DIFFERENT SPIDERS

A big mistake is made by those who call spiders insects.In fact, spiders belong to the order of arthropods of the phylum Arthropoda. The main difference between spiders and insects is the number of legs. Insects usually have only 6 of them, while spiders have as many as 8 legs. In general, of course, they are close relatives, because both spiders and insects belong to the phylum arthropods.

There are about 41,000 species of spiders in nature!

The spider's body consists of two parts connected by a stalk: the cephalothorax and abdomen (opisthosoma).

Located on the cephalothorax oral apparatus, consisting of chelicerae, lower lip and chewing lobes, pedipalps and four pairs of legs. All spiders have arachnoid warts on their abdomen, in most cases there are three pairs of them.

The abdomen generally has an oval shape, less often round, angular, and sometimes has a very elongated, worm-shaped shape.

Spiders have 8 or 6 eyes, very rarely some species have 2 eyes.

The cephalothorax contains two nerve ganglia, which form many brain nerves and they diverge from the brain to the legs, eyes and other organs of the spider. The brain can occupy from 20% to 30% of the volume of the cephalothorax.

The only spider for which plant food is the jumping spider, which lives on acacia trees (it is this tree that it feeds on). In generalVegetarian spiders do not exist; they are all predators. They usually feed on their relatives - insects.

Having caught prey with the help of a web, the spider kills it with poison and injects digestive juices into it. After some time (usually several hours), the spider sucks out the resulting nutrient solution.

The web is a protein mass secreted by special glands of the spider. At the moment of release, the web is a liquid mass that quickly hardens in air, forming threads. Cobweb - very durable material, in its stability it surpasses even steel equal thickness. The main components of the web are proteins, one of which is responsible for strength, and the second for elasticity. Each thread of the web is coated with a special adhesive substance that holds the prey in case it tries to escape.

Spider is capable of reproduction various types threads, so not all webs are the same. For different types different glands are responsible for the threads. The main type of web is the one along which the spider descends to any place, and along which it returns to its original position. Young spiders can create such a web, which they use as a parachute; the wind picks it up and carries the spider in the desired direction.

Spiders' nests are also built from cobwebs.

In a single species of spider, all types of glands are not found at the same time.

Spiders often use spider silk repeatedly, eating fishing threads damaged by rain, wind or insects. It is digested with the help of special enzymes.

Male spiders, as a rule, are much smaller than females, and their coloring is different.Many females eat males after fertilization.

Most species of spiders bite people only in defense, and few species can cause more harm than a mosquito or bee.

The science that studies spiders is called arachnology. And the fear of spiders is arachnophobia.

1. The largest spider

Theraphosa Blonda or Goliath tarantula is the most big spider in the world. Capable of huntingfrogs, toads, lizards, mice and even small snakes.

It was first described by the French entomologist Latreille in 1804. Distributed in tropical forests South America. Lives in deep burrows, entrance towhich are lined with cobwebs.

The size of the body of the female Theraphosis Blonda reaches 90 mm, and the male - 85 mm, with the legs straightened, the dimensions of Theraphosis Blondareach up to 25 centimeters. The size of the dorsal shield is the same in both length and width. The body is dark browncolor. The legs are covered with a mass of reddish-brown hairs.

The largest representative of this species was discovered in Venezuela in 1965: the span of its paws reached 28 centimeters(according to the Guinness Book of Records).

In Cambodia, fried tarantula spiders are considered a delicacy. Before preparing the tarantula, its stinging hairs are removed.

2. The smallest spider- Patu digua reaches only 0.37 mm.

3 . The most poisonous spider

Brazilian wandering spider, considered the most poisonous in the world.Sometimes it is also called banana spider or a Brazilian hunter.This spider has the largest venom glands, they reach 10 millimeters in length. The amount of one portion of poison is enough to kill 225 mice. Hundreds of accidents involving spider bites are reported every year.Fortunately, there is an antidote for its poison.

In South In America, these spiders are usually found in houses, hiding in boots, hats and other clothing, and if they are disturbed, they bite. In addition to the fact that they have the most dangerous poison, they also differ from other spiders in their increased aggressiveness and speed of movement.

These spiders got their main name becausethat they do not sit still and do not weave webs, but are in constant movement, moving from place to place.Young individuals eat fruit flies and small crickets. Adults eat crickets and other large insects, Aalso small lizards and mice.

Wandering Spider entered into the Guinness Book of Records.

4. The most famous spider - Black Widow.

Black Widow Spider, a common name for any of several long-legged, smooth-bodied spiders found in the Tropics,in the southern United States, and also found in northern Canada.They spin simple webs in places protected from the sun, often in crevices. Adult female has a glossy black color (hence the name Black), body diameter is approximately 1 cm, legs length is up to 5 cm.the dorsal side of the abdomen has a characteristic red mark,similar to hourglass. The female is very poisonous spider

Males are less common and are harmless. Males have four pairs of red dots located along thesides of the abdomen. After mating, the female devours the male, hence the name “black widow”.

The black widow spider is dangerous to humans - it produces a neurotoxin that causes severe pain, muscle cramps and evenparalysis. Their bites are very dangerous, butAntidotes have long been created that allow one to recover from poison in a few days. But insectsneurotoxins paralyze so quickly that the spider often starts eating when the victim, although not moving, is still alive.

By the way, most species of “black widow” behave rather timidly, preferring flight to attack. Disturbed spideroften pretends to be dead, with its paws tucked in, and runs away only if it considers that the danger has passed. Per person"black widows" attack only if they are teased or frightened, and the spider itself is not aggressive and attacks people exclusively whencase of their defense.

5. Karakurt

Karakurt - close relative Black widow, these spiders belong to the same speciesLatrodectus, and are similar in appearance.

In the photo: a young female karakurt. With age, the spots on the abdomen first become white, and thencompletely disappear. Photo taken in Russia, Astrakhan region

Karakurt, unlike the Black Widow, is quite common in steppe zone Central Asia, and alsoin the Caucasus and Crimea. Karakurt is a small spider, its length usually does not exceed twenty millimeters (this is the maximumthe length of females, males do not exceed seven millimeters in length).

The habitat for karakurts is virgin lands, wastelands, banks of irrigation canals, and so on. The female findsmakes a hole in the soil and makes a den there. Very often karakurts settle in rodent burrows. Before entering the lair, the femalestretches a catchy, incorrectly woven web.

Karakurt eggs spend the night in cocoons previously suspended in the lair. In April, young spiders are selected forsurface and scatter in the wind along with the cobwebs.

Karakurt is a prolific spider,outbreaks occur every ten to twelve years mass reproduction. Adults are the most poisonousfemales. Let us recall that the poison of karakurt is fifteen times stronger than poison rattlesnake.

After a bite, a small spot remains on the body, which quickly disappears. Within fifteen minutes sharppain in the abdomen, lower back and chest, then numbness in the legs. The patient becomes lethargic and cannot sleep due to severe pain.

Recovery occurs in about three weeks, or even more.Most effectiveAntikarakurt serum is considered a medicine.

It does not attack animals or humans; it can bite only if someone literally steps on it.

6. Tarantula

Tarantula, a spider that is very widespread in America and southern Europe, whose bite is not dangerous.Tarantulas live in deep(about 50 centimeters deep) minks. At night they hunt insects.

The tarantula's body length is about three centimeters.

They feed on insects and a variety of small animals. Large variety this group can bite people suchthe bites are often painful but not fatal.

7. The strangest spiders- "horns".

The belly of these spiders is amazingbright yellow, white and black colors. Six strong spines, long and smooth, emanate from the border of the abdomen.The female's abdomen is wide, flattened, angular, with six spines, two of which are very long. Probably the spikes are needed forprotection from predators. Bright yellow or red stripes run across the abdomen. Spider warts are raised. Malesmall, without noticeable spines.

Size: female - up to 10 mm (body width - up to 20 mm), male - up to 4 mm.

Habitat: forest edges and gardensIndia and Southeast Asia, Australia.

Horned spiders weave excellent webs and make a trap loop for the victim. Their webs are usually woven at a distance of two metersfrom the ground. Their victims are most often small insects. Interestingly, if these spiders live in a community, thenThey share the caught prey regardless of whose net it fell into.

A distinctive feature of these spiders is their bright color and spines, which are needed to save them from other predators.

8. Most dangerous for children- Sydney leukoparachnoid spider.

Belongs to the most dangerous spiders in the world, but fortunately they live very far from Russia - in Australia.They weave (as can be seen from theirnames) watering-like or pipe-like web and live in a burrow up to 40 cm deep. They are very aggressive and alwaysready to attack. Their massive fangs can even bite through children's nails. Unfortunately, adult males leavetheir burrows and begin to travel, often “visiting” human dwellings, especially after a summer rainstorm. So, when traveling around Australia, be careful and careful - thesespiders cannot climb into a bed or table along a smooth metal or wooden leg, but they can “climb” intoclothes, shoes or towels thrown on the floor.

9. Spiders are spider hunters- are called "wolf spiders".

Wolf spider, a common name for any group of spiders that have a ground dwelling and hunt spiders. Wolf spidersare among the most common and visible spiders.

There are more than 2000 species of wolf spiders. These are brownish spiders that run (prowl) back and forth in whole “flocks”, like real wolves. This is quite unusual among spiders, as most spiders can't stand each other.

Probably because they often gather in packs and are brownish in color, they were given the name wolf spiders. In EuropeThere are several hundred species of wolf spiders. Most wolf spiders have strongbodies and long legs. Their bodies are low to the base for easy yaw. Wolf spider species are similar ingeneral shape, but their bodies vary in size, ranging from 2 mm to 40 mm in length. They typically have two verylarge eyes in the middle of their heads.

Wolf spiders have very good eyesight,which they need to hunt during the day.Wolf spiders generally determinelocate their prey by sight, but can also use contact to determine the nature of the prey. Theyuse their front legs to grab prey, then bite and crush it with strong fangs.

Wolf spiders are very common in any region of Russia. They can winter infield, prefer sparse vegetation. IN summer months leave the field to the side of the road, although the vegetation there is morethicker than in the field. This is probably due to low humidity and high temperature in the field in the summer.

The female wolf spider lays her eggs in a large sac that can be almost as big as her own body.

She attaches the egg sac to her body and wears it until the eggs hatch. Then she tears the bag and takes itinto the burrow, where the offspring remain for another week. Many female wolf spiders are very good mothers: theylay their eggs in a cocoon, which they carry with them almost until the young hatch. Some species have young spidersclimb onto the mother's back and travel in this way for one to two weeks.

Wild animals

Small multi-legged creatures that inhabit our Earth in abundance, ordinary person cause delight and amazement if met in conditions wildlife, or disgust and a feeling of disgust if found at home. Some peoples inhabiting Asia and Africa have a pronounced culinary interest in insects and spiders, explaining it by the high protein content in the body of these animals and exceptional taste qualities fried locusts, grasshoppers and tarantulas.

Definition

Spiders- these are animals belonging to the order Spiders of the class Arachnid type Arthropods.

Insects- these are animals belonging to the class of Insects of the Arthropod type.

Comparison

Today there are about 42 thousand species of spiders on Earth. They are distributed everywhere. Apart from the jumping spider, all other animals of this order feed on other animals - insects, other spiders or small animals.

Insects are ubiquitous. To date, more than a million species have already been discovered, described and studied.

The spider's body consists of two sections - the cephalothorax and abdomen. Both parts are connected by a thin, short stem. On the cephalothorax there is a groove separating the head and chest parts. It is from the spider’s cephalothorax that the chelicerae “grow”—the spider’s two- or three-membered oral appendages with ducts of poisonous glands—and the entire “magnificent eight” of seven-membered legs. In the cephalothorax there are nerve nodes that form the central nervous system, brain and sensory organs, represented by simple eyes. Sensory hairs that detect odors and sound waves are located on the segments of the legs.

The body of insects consists of three sections - head, thorax and abdomen. On the head they have complex-faceted or simple eyes, antennae and mouthparts - sucking, gnawing, licking or piercing. The six segmented legs of insects are attached to the thoracic region of the body. In some subclasses of insects, a pair of wings also “grows” from the chest.

In the abdomen of the spider there is a heart that drives hemolymph, “book lungs”, a digestive gland, Malpighian glands, gonads and a spinning apparatus. Thanks to the glands located in it, the spider produces a web. Half of it chemical composition is the protein fibrin.

In the abdomen of the insect there are Malpighian vessels, genital organs with a diverse set of copulatory apparatus, which in some orders sometimes plays the role of a sting.

External structure of an insect using the example of a bee

Spiders catch their food using a web and inject poison (digestive juice) into it. After waiting several hours for the poison to dissolve the internal contents of the victim, the spider sucks out this nutrient solution using a sucking-type mouth opening located at the top of the tubercle between the chelicerae.

Insects are omnivores, they eat plants, animals, devour corpses, and are characterized by cannibalism.

Female spiders are in most cases larger and more colorful than males. Often, after mating, spiders eat their males. The color of all types of spiders uses only two color pigments - bilin and guanine.

In insects, sexual dimorphism and sexual polymorphism are noted - two types of females in bees, three types of males in stag beetles. For life cycle Insects are characterized by metamorphism, in which the animal goes through the stages of larva, pupa and imago. Insects can jump, fly, swim, live underwater, and glow in the dark. They are able to communicate using sounds and have the ability to excellently navigate in space.

Conclusions website

The number of insect species exceeds the number of spider species.
Spiders have 8 legs, insects have 6.
The body of spiders consists of two sections, while that of insects has three.
Only spiders are capable of producing webs.
Spiders produce venom that is intended for external digestion.
The life cycle of insects involves transformations - metamorphism; spiders do not have this phenomenon.
The nervous system, behavior and communication of insects are much more complex than those of spiders.

Krinitsyn Oleg

When I was little, I was very afraid of spiders - I ran away and hid from them. And when I grew up, I decided to learn more about them, so as not to be afraid, and maybe even make friends with these mysterious creatures.

In the summer I visited my grandmother in the village, I had the opportunity to watch the spiders. I even overcame my fear and began to pick them up and see how they would behave. It was very interesting. Adults knew a little about the life of spiders, so I began to look for material in books. I was able to learn a lot of interesting things about these amazing animals from encyclopedias. I was very interested to find out: how many types of spiders there are; what species are the spiders I observed; how they differ from each other; what do they eat; how they move along walls and ceilings. Also, I wanted to find an answer to the question: “Where do they get the web?” I also wanted to figure out why a spider is not an insect, because they are so similar. Many consider them disgusting, dangerous, disgusting. Therefore, I would like to change the opinion about spiders, tell adults and classmates why spiders are interesting and useful.

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Department of Education

Administration of the municipality

Nadymsky district

Municipal educational institution

"Average secondary school № 6
with in-depth study of individual subjects" Nadym

Research work

Krinitsyn Oleg,

2nd grade student.

Pedagogical supervisor:

Katyukova Olga Viktorovna,

primary school teacher.

Nadym

2013

		Page
	Introduction
	Main part
2.1.	Who are spiders?
2.2.	Why is a spider not an insect?
2.3.	Interesting facts about spiders
2.4.	Spiders I watched in the village this summer
2.4.1.	Spider - Haymaker
2.4.2.	Funnel Spiders
	Conclusion
	References

I.Introduction

Of the creatures that live near us, spiders are without a doubt the most interesting... Karl Frisch

Purpose of the study:study external structure spiders, find the differences between spiders and insects, make sure that spiders are not insects.

Tasks:

study the literature on the topic of the research work;
compare spiders and insects;
find out what spiders live in your grandmother’s house and garden;
watch their lives
present the work to the children.

Hypothesis: Spiders have no signs of insects, they are not insects

I have identified research paths and methods:

studying sources of information;
observation;
conversation;
analysis;
practical work.

Object of study: spiders.

Subject of research: life of spiders.

II. Main part

2.1.Who are spiders?

From the encyclopedia I learned that spiders are the most large squad arachnids. Spiders (lat. Aranei ). There are 35,000 species described and this number must rise to approximately 50,000, since all spiders have not yet been studied.

Spiders appeared on Earth so long ago that it is even difficult to imagine (approximately three hundred and fifty million years ago), the ancestors of spiders first came to land from the water in which the entire animal world lived in those distant times.

Spiders appeared a hundred million years earlier than flying insects, and when people appeared, spiders already felt like masters and looked like they do today.

Spiders are currently one of the thriving groups of animals. It is difficult to find a place in nature where spiders do not live. They have mastered everything natural areas Lands from deserts and tropical forests to the islands of Antarctica. Everest explorers found a spider at an altitude of 7,000 meters. Spiders survive where other animals die, for example, in highlands and caves. Spiders are very hardy and interesting animals.

All spiders are predators, but since they do not possess good eyesight, they lie in wait for their prey. Spiders catch prey on their webs or by other means. Spiders that catch prey with webs are called web spiders. With the help of the hiletser, the spider injects poison into the victim. After several hours, the prey turns into a thick mass and the spider “drinks” it. Yes, yes, exactly “drinks.” Spiders eat only liquid food. They suck out the victim, leaving behind a dry shell. Even such giants as the bird spider “drink” their victims as if through a straw. Moreover, their menu includes not only insects, but even lizards and birds. Sometimes they eat each other.

However, there are spiders that do not use webs for hunting. They overtake prey by jumping, wait in ambush, etc. The hunter's victim can be: frogs, small rodents, insects...

Spiders, scorpions and ticks are similar to each other, so they are classified as arachnids. Spiders are close to insects in a number of ways, but clearly differ from them, and these groups are only very distantly related.

2.2 Why a spider is not an insect

In order to figure out whether a spider is an insect or not, I decided to study and compare the structure of a spider with the structure of insects.

I learned that spiders have 2 body sections: the cephalothorax and abdomen. Spiders have 4 pairs of legs and pedipalps that are very similar to paws. The bases of the pedipalps are transformed into chewing organs.

Spiders have up to 8 simple eyes. Despite this large number organs of vision, many arachnids see very poorly. So bad that this distance is on average 30 cm.

Spiders do not have a skeleton inside their body. They have a hard outer shell called an "exoskeleton". As the spider grows, it needs to shed its old, tight shell. When molting, the spider climbs out of the old body and waits for its new delicate skin to dry and harden. At the moment of molting, spiders are especially vulnerable.

At the end of the abdomen there are arachnoid warts. The substance coming out of them hardens and turns into threads of extraordinary strength.

Insects, Insecta - a class of creatures with the absence of vertebrae and the segmented structure of legs. They differ in body structure (divided into 3 sections - head, thorax and abdomen), one pair of antennae, 3 pairs of legs on the chest and mainly 2 pairs of wings. Some insects secrete through special organs various substances: cobwebs, silk, wax, poisons. The skin of insects is formed mainly from chitin, which forms a strong exoskeleton. The cavities are filled with the so-called fat body.

Insects have two eyes. They feed on plant and animal products. Insects in a colossal number of species inhabit the earth. They appeared in distant geological periods (starting from the Carboniferous). About 10,000 species are known in fossil form.

Thus, we can conclude: spiders are not insects. They belong to the class of arachnids, and differ from insects primarily in their body structure. The spider's body consists of a cephalothorax and abdomen, breathing is carried out by pulmonary sacs and trachea. In insects, the body is divided into the head, chest and abdomen, and they breathe exclusively through the trachea. In addition, the spider has 4 pairs of legs, while insects are arthropods that have 3 pairs of legs and 2 pairs of wings . Also, an insect can be distinguished from a spider by the presence of antennae, but spiders do not have antennae.

Comparison table

“What is the difference between spiders and insects”

2.3 Interesting facts about spiders

It should be noted that spiders, especially tarantula spiders, have a certain amount of intelligence; they can even distinguish between their own and others. These spiders are often used as pets. They are also very subtle and sense the mood of their owner, and therefore you can even play with them, they are even able to protect their owner if he is in danger, and they can also dance to music.

Spiders of the species Cyclosa mulmeinensis from Singapore are able to make a copy of themselves from debris and remains of victims caught in the net. The dummy has “legs” and reflects light like its prototype, and a blow of wind can create the impression that it is moving. In this way, these spiders deceive the wasps that hunt them, since the dummy is located in the most visible place of the web, and in most cases, predators attack it, allowing the real spider to hide.

Spiders of the genus Cyclocosmia, living in Asia and North America, have original look: Their abdomen ends in a hard disc-shaped surface on which numerous grooves form an intricate pattern. In the species Cyclocosmia truncata, for example, this pattern resembles a seal. When this spider is in danger, it crawls into its burrow and plugs the entrance with its disk, which coincides with the entrance hole in diameter.

Spiders of the species Theridion grallator, living only on Hawaiian Islands, have an amazing body color, reminiscent of a smiling human face, and the coloring of each individual is unique. Presumably, such a pattern should scare away their only enemies, birds.

It is possible to sew clothes from cobwebs, but it is several orders of magnitude more difficult and more expensive than from ordinary silk obtained from silkworm. The first documented mention of such clothing dates back to 1710, when the French scientist and entrepreneur de Seu Hilaire made gloves and socks from “spider silk” and presented them to King Louis XIV. And more recently in American Museum natural history exhibited a piece of fabric slightly larger than 3 square meters. To obtain it, several dozen workers caught golden spiders in Madagascar for 4 years, then carefully removed the threads from them and released them back into nature.

The web has enormous strength potential. The thread made from their web, as thick as a pencil, will be able to stop Boeing in its tracks. full speed ahead. IN at the moment ultra-lightweight and durable body armor using spider webs is being developed.

2.4 Spiders I watched in the village in summer

At my grandmother's in the village, I watched the hay spider and the funnel-web spiders.

2.4.1 Spider - Haymaker

Haymaker - we all know this amazing creature from the arachnid family with very long legs. If you grab a haymaker's leg, it will easily come off and twitch convulsively for many minutes. It is because of this movement, similar to the movement of a scythe, that the commonly known names “mow spider” or “haymaker” arose.

The haymaker's leg comes off so easily that it seems as if it is very loosely attached to the body. Actually this is not true. The throwing of the leg occurs voluntarily and depends on a special muscular movement. This phenomenon is called autotomy - self-mutilation. The autotomy of the legs in the haymaker, like the autotomy of the tail in lizards, serves for salvation from enemies. Approaching its prey, the predator first of all stumbles upon a palisade of limbs, and a severed and twitching leg distracts it from the harvester running away on its remaining legs. Therefore, you can often find harvesters with an “incomplete” set of legs.

We will never see a haymaker weaving a web, making a lair for itself, or descending on a thin web thread - these arthropods do not have arachnoid warts.

You can meet haymakers on a tree trunk or on a fence, on the wall of a house or in cracks in the bark, under stones and in the litter in a forest, garden, park, field, or vegetable garden. Deciduous and mixed forests. In mountainous areas, these animals are found on rocks, in scattered stones and caves.

Haymakers go hunting at dusk or at night. They feed on insects, small spiders and other invertebrates.The biggest threat to spiders is the spiders themselves. In case of hunger strike, they even kill their offspring.

In my grandmother’s village, I was able to observe such a story. I put two haymakers in a plastic cup and fed them flies. But for some time I forgot about them and did not feed them, and two days later I discovered that there was one live spider in the glass - which was larger, and the other was eaten.

2.4 Funnel spiders

Perhaps one of the most famous spiders in Russia. He really loves to live in houses and households. buildings. Usually it weaves its network somewhere in a corner on the ceiling or behind a closet. In general, where the housewife’s broom cannot reach it. If he reaches it, the spider will not be upset: by the next morning he will mockingly build a new web in another corner. In the middle of the house spider's web there is always a funnel that leads into a small hole - its home. Here he sits and waits for prey - flying insects. As soon as someone touches the web, the owner jumps out from his hiding place and instantly deals with the troublemaker. There is usually a lot of dust in a person’s home, so very soon the web becomes dirty. It is his web that sticks to the ceiling and constantly sways.

The male grows up to 10 mm (not taking into account the length of the legs), the color is yellow-gray with brown spots. The female is larger, the color is the same as the male. Sometimes, if there is a lot of food, they grow to impressive sizes and sometimes crawl along the walls, scaring children and women.

The spider is timid and never attacks people. However, he can still bite if you accidentally crush him. However, the poison is completely harmless to humans and does not cause any visible consequences. The house spider is useful because it exterminates various insects that are harmful to people right in the apartment: flies, mosquitoes and various moths.

I also learned very much interesting fact: if you play at home musical instruments, then the spider will come out of its hole to listen to you, or even begin to “dance” on its web. It turns out that the problem here is not at all the musical preferences of spiders. The music shakes the web like small insects, and the spider, in anticipation of dinner, comes out to check: “Who is shaking my web?” Finding no one, he is probably very surprised and watches for a while, puzzled. And then he even tries to “shake off” the invisible insect from the web.

Funnel spiders, by the way, react very sensitively to changes in temperature and humidity. Therefore, they can serve as a kind of living barometers. Previously, house spiders were completely trusted in such matters.

III. Conclusion

Some people are disgusted by the sight of spiders or afraid of them. This is often due to the fact that we know very little about these eight-legged animals. However, only a small number of spider species are dangerous to humans, and they do not live in Europe. Spiders are not insects, as many people think; they feed on them. Many spiders weave webs that trap their prey. And this makes spiders useful for people: they free us from flies, mosquitoes and other insects that often bother us. Without spiders, we would be stuck, so to speak, with insects.

While researching the life of spiders, I learned a lot of interesting things, read various literature about the life of animals and came to the following conclusion:

Spiders are not insects.

The life of spiders is very interesting.

They live near us different types spiders

The spider obtains its food using a web.

Spiders predict the weather, they are experts in weather changes.

Spider is man's friend!

From now on, I intend to study the life of these interesting animals even more deeply. And I will definitely share my knowledge and observations with my classmates, telling them about the amazing and diverse world spiders and their benefits for humans.

References

"Mysteries of the Wild"; Moscow "ROSMEN", 2004
“My first book about animals”; Moscow "ROSMEN", 2006
"Around the World"; A. Tikhonov, Moscow “Bustard plus” 2008 https://accounts.google.com
Slide captions:
Why is a spider not an insect? Of the creatures living next to us, spiders are, without a doubt, the most interesting... (Karl Frisch) Prepared by Oleg Krinitsyn
Preface When I was little, I was very afraid of spiders - I ran away and hid from them. And when I grew up, I decided to learn more about them, so as not to be afraid, and maybe even make friends with these mysterious creatures. In the summer I visited my grandmother in the village, I had the opportunity to watch the spiders. I even overcame my fear and began to pick them up and see how they would behave.
Who are spiders? Spiders appeared on Earth a very long time ago, approximately three hundred and fifty million years ago, earlier than flying insects, and when people appeared, spiders already felt like masters and looked the same as they do today. It is difficult to find a place in nature where spiders do not live. Spiders survive where other animals die, for example, in highlands and caves.
Who are spiders? All spiders are predators, but since they do not have good eyesight, they lie in wait for their prey. Spiders catch prey on their webs. They inject poison into the victim. After several hours, the prey turns into a thick mass and the spider “drinks” it. Yes, yes, exactly “drinks.” Spiders eat only liquid food.
Why is a spider not an insect? Spiders are close to insects in a number of ways. In order to figure out whether a spider is an insect or not, I decided to study and compare the structure of a spider with the structure of insects. The spider's body consists of a cephalothorax and abdomen, breathing is carried out by pulmonary sacs and trachea. In insects, the body is divided into the head, chest and abdomen, and they breathe exclusively through the trachea.
Why is a spider not an insect? In addition, a spider has 4 pairs of legs, while insects are arthropods that have 3 pairs of legs and 2 pairs of wings. Spiders have up to 8 simple eyes. But despite this they see very poorly. This distance is on average 30 cm. Insects have two eyes. Also, an insect can be distinguished from a spider by the presence of antennae, but spiders do not have antennae. Thus, we can conclude: spiders are not insects.
Interesting facts about spiders It is interesting that spiders, especially tarantula spiders, have a certain amount of intelligence; they can even distinguish between their own and others. These spiders are often used as pets. They also very subtly sense the mood of their owner, and therefore you can even play with them, they are even able to protect their owner if he is in danger.
Interesting facts about spiders Spiders of the species Cyclosa mulmeinensis from Singapore can make a copy of themselves from debris caught in a net. In this way, these spiders deceive the wasps that hunt them.
Interesting facts about spiders Spiders, found only in the Hawaiian Islands, have an amazing body color that resembles a smiling human face, and the color of each individual is unique. Presumably, such a pattern should scare away their only enemies, birds.
Watching spiders At my grandmother's in the village, I watched the hay spider and the funnel-web spiders.
Haymaker You can meet harvesters on a tree trunk or on a fence, on the wall of a house or in cracks in the bark, under stones. The harvestman never spins a web - they do not have spider warts. If you grab a haymaker by its long leg, it will easily come off and twitch convulsively for many minutes. It is because of this movement, similar to the movement of a scythe, that the name “haymaker” arose.
Haymaker Haymakers go hunting at dusk or at night. They feed on insects and small spiders. But sometimes they eat each other. In my grandmother’s village, I put two haymakers in a plastic glass and fed them flies. Then I forgot about them and didn’t feed them, and two days later I discovered that there was one live spider in the glass - which was larger, and the other one had been eaten.
Funnel-web spider The funnel-web spider is one of the famous spiders in Russia. Likes to live in houses. Usually it weaves its network somewhere in a corner on the ceiling or behind a closet. In the middle of the web there is always a funnel that leads into a small hole - his home. If someone touches the web, the spider jumps out from its hiding place and instantly grabs the troublemaker.
Video Feeding the Funnel Spider
Conclusion The spider is timid and never attacks people. However, he can still bite if you accidentally crush him. However, the poison is completely harmless to humans and does not cause any visible consequences. The house spider is useful because it exterminates various insects that are harmful to people right in the apartment: flies, mosquitoes and various moths. Some people are disgusted by the sight of spiders or afraid of them. This is often due to the fact that we know very little about these eight-legged animals. While researching the life of spiders, I learned a lot of interesting things, and came to the main conclusion: The spider is a friend to man!

Not only inquisitive schoolchildren, but also many adults are interested in the question: is a spider an insect or not? Indeed, at first glance it may seem that the answer is obvious, and spiders are one of the types of insects, but this is not so. They belong to a separate class of arachnids, because they have many differences with insects.

Spiders appeared on our planet a very long time ago, about 400 million years ago. It is believed that they descended from a crab-shaped ancestor. Insects appeared almost 100 million years later and created a separate class. Today, about 40 thousand species of arachnids live on earth. If we look at the anatomy of these creatures in detail, then questions like “Is a spider an insect or not?” should not arise. Everyone knows that insects have six legs, but arachnids have eight, and they also have eight eyes, only some species have six or two. These creatures do not have teeth, but they have hook-shaped jaws with special channels designed to penetrate the poison into the body of the victim.

Doubts about whether a spider is an insect or not will disappear immediately if you consider how it feeds. While praying mantises eat captured flies, arachnids cannot do this because they have extraintestinal digestion. They inject digestive enzymes into the victim, which turn the insect into soup, and the spiders can only suck out the contents of the shell.

Many creatures know how to spin a web, but for them it will not be as strong and elastic as the trap for victims that the spider prepares. Reproduction also forces these creatures to weave special cocoons to preserve clutches of eggs and small spiders. If you compare a web with steel, the first will be five times stronger than the second, and the threads as thick as a pencil cannot be broken by a plane crashing into the network.

It is not clear why many people ponder the question of whether a spider is an insect or not: there are a significant number of differences between the two classes. The body of these creatures is divided not into three, but only into two sections: the abdomen and cephalothorax. They make webs from fluid secreted from warts located at the end of the belly. From this material, spiders build houses for themselves, make flying carpets on which they travel long distances, weave cocoons for eggs, and hunt insects with nets.

These creatures move quite nimbly through their webs, while mosquitoes, flies and other unfortunate creatures simply stick to it. The fact is that spiders weave sticky and non-sticky threads, the former are needed to catch prey, and they move along the latter. Even if they accidentally fall on the sticky part, they will not get confused, since their body is coated with fat.

Modern science has already given an exact answer to the question: “Is a spider an insect or not?”, distinguishing these creatures into a separate class. IN middle lane There are no arachnids in Russia that are dangerous to human life, although it is necessary to behave carefully with them. Spider never will attack first, he only defends himself or bites when scared. A bite can only be accompanied by a burning sensation, severe pain and fever. But there is also dangerous representatives This species: the most famous are the tarantula and karakurt. Their bite causes general poisoning of the body, which sometimes leads to death.