How many insects are on earth. How many insects live on Earth? Insects with full metamorphosis

How many insects are on our earth

Insects are the most numerous group of organisms on Earth. In fact, there are about 8 million species of insects (what science knows today). It is estimated that there may be up to 30 million species of insects on the planet. Thousands of new species are discovered every year.

Approximately 80% of insect species are herbivorous, 15% are predators, 5% are bloodsuckers and corpse-eaters.

In total, there are supposedly 9.8 billion (10 ^ 18) billion insects on Earth. Insects are so numerous on Earth that for every person living on Earth, there are approximately 1.4 billion insects (!) This is 6 times more than fungi (1.5 million) and 36 times more than plants ( 250,000).

Behind these numbers lies a subtle reality: some species of insects are endangered. This could be disastrous, especially for agriculture.

Probably to some ears it will sound like a joke “Castrostrophic consequences for agriculture”, because farmers spend a huge amount of effort and insecticides on the fight against “harmful insects”, dreaming of the day when there will not be a single insect left on the earth.

No one realizes how important insects are in the food chain and in the balance of our ecosystems.

Here, for example, is the great Kalosoma (beetle), Calosoma sycophanta- a great pine lover: this beetle destroys up to 200-300 caterpillars in the summer, and also eats silkworm larvae and cocoons. He perfectly climbs trunks and thin branches, hunting for caterpillars. Unlike most ground beetles, it flies well. Voici, voilà.

In addition, insects are natural pollinators of plants. The day the insects are gone, farmers will realize the importance of insects. I'm willing to bet that the big phytosanitary companies have already planned to sell drones and robotic plants to replace insects.

What kinds do you know?

Before you start practicing, you can talk with your child about domestic insects. The guys know much more about them than about the wild ones. Domestic insects surround us everywhere: in the apartment, in the house, in the apiary. Bees are also domestic animals, as they are tamed by people and used for purposes beneficial to mankind. Ask what insects can live in the baby's apartment. It doesn’t have to be cockroaches (the most expected answer): they are now being actively removed, and they practically do not settle in new well-kept houses. Spiders can also live in the apartment, which often descend on their web. What insects living in an apartment look like can be seen in the photo on our website.

Tasks for children

To introduce your child to the types of insects, I suggest printing out cards and a poster with photos on the topic of insects for children. Among them there are familiar to us, and rare, endangered species.

Poster

Your child will get to know insects such as butterfly, fly, grasshopper, praying mantis, dragonfly, spider (not an insect), locust, caterpillar (insect larva, you can’t call it a full-fledged insect), beetle, bee, ant, ladybug, bumblebee, worm, wood lice, centipede, wasp, rhinoceros beetle, large black beetle and others.

You can print a poster with a photo of insects, hang it in a prominent place for the child, go up to him from time to time and introduce the child to different types of insects.

The kid will get acquainted with various types of insects, expand his horizons, memory, attentiveness, develop fine motor skills fingers.

Games with cards and photos of insect species will help your child remember the main insects and bring many positive moments. With their help, you can train visual memory. Learn the names of insects with your child, and then select a few cards and arrange them in random order. Ask your child to try to remember the order in which the images are arranged. Then turn the cards over and ask the baby to name which card which insect is drawn on. This exercise is great for developing visual memory. In addition, the baby will quickly learn the names of the representatives of the fauna.

Educational materials

Endangered Insects for Kids
Insects with names on English language.
Pictures with insects (black and white version).
Insects and spiders for kids. Types of insects in the house.
Types of stinging insects.

How to play with them?

1. Print the file, cut into cards.
2. Show the child a card and say the name of this or that insect. You can tell a few words about the insect to the child.
3. When the child learns the names of all insects, invite him to choose from 2 options. For example, show 2 cards - a butterfly and a fly and ask where the butterfly is, if the child cannot speak, let him point with his finger.
4. Further more difficult option- add more cards and offer to find, for example, ladybug.
5. Memory game - print 2 copies of the insect cards. Flip 'em up reverse side and look in turn for pairs for each insect. Start with a small number of pairs of insect species, then add more.

These games are suitable for kids aged 1 and up.

Why does the child need it?

Man is part of nature. But nature also belongs to insects. Today, a person mostly spends time in an apartment, seeks to restore order there, and perceives insects as unwanted visitors to his home. Hence the hostility that arises in us, which we experience when looking at these small inhabitants of the planet. Even if we are asked to look at a photo of an insect, unpleasant goosebumps will surely run down our backs.

Of course, not all insects can be acceptable to us, but children must understand that there are rare species listed in the Red Book. They cannot be destroyed. Show the children photos of these insects so that preschoolers can imagine what they look like. Perhaps children will never meet these representatives of the fauna in their lives, but there will be an understanding that nature must be protected.

The tasks presented on our website with photos are very colorful, bright. They will interest the child, which gives you an opportunity to develop children's creativity, memory and thinking.

Video presentations

conclusions

So, insects can be rare, wild, living in an apartment or house. Thanks to cards, a poster and a photo, children will be able to get to know them. The children must understand that they do not need to be afraid. Having met an insect in the apartment, you do not need to strive to kill them. Let him go, let him fly his own way. The tasks that are on our website will contribute to the development of memory and creativity. Thanks to them, children will understand that insects are the same inhabitants of the planet as we are.

Insects are the youngest of the invertebrates and the most numerous class of animals, numbering more than 1 million species. They have completely mastered all habitats - water, land, air. They are characterized by complex instincts, omnivorousness, high fertility, for some - a social way of life.

During development with transformation, there is a division of habitat and food sources between larvae and adults. The path of evolution of many insects is closely related to flowering plants.

More highly developed insects are winged. In the circulation of substances in nature, gravedigger beetles, dung beetles, consumers of plant residues play an important role, and at the same time, insects - pests of agricultural plants, gardens, food supplies, leather, wood, wool, and books cause great damage.

Many insects are carriers of pathogens of animal and human diseases.

Due to the reduction of natural biogeocenoses and the use of pesticides, the total number of insect species is decreasing, therefore 219 species are listed in the Red Book of the USSR.

General characteristics of the class

The body of adult insects is divided into three sections: head, thorax and abdomen.

• Head, consisting of six merged segments, distinctly separated from the chest and movably connected to it. On the head there is a pair of jointed antennae or screeds, a mouth apparatus and two compound eyes; many also have one or three simple eyes.

  Two complex, or faceted, eyes are located on the sides of the head, in some species they are very strongly developed and can occupy most of the surface of the head (for example, in some dragonflies, horseflies). Each compound eye consists of several hundred to several thousand facets. Most insects are blind to red but can see ultraviolet radiation and are attracted to them. This feature of insect vision is the basis for the use of light traps, which emit most of the energy in the violet and ultraviolet regions, for collecting and studying the ecological characteristics of nocturnal insects (certain families of butterflies, beetles, etc.).

  The mouth apparatus consists of three pairs of limbs: upper jaws, lower jaws, underlip(the fused second pair of lower jaws) and the upper lip, which is not a limb, but is an outgrowth of chitin. The chitinous protrusion of the bottom also belongs to the oral apparatus. oral cavity- tongue or hypopharynx.

  

  

  

  Depending on the method of feeding, the oral organs of insects have a different structure. There are the following types of oral apparatus:

  • gnawing-chewing - elements of the oral apparatus look like short hard plates. Observed in insects that feed on solid plant and animal food (beetles, cockroaches, orthoptera)
  • piercing-sucking - elements of the oral apparatus have the form of elongated hair-like bristles. Observed in insects that feed on plant cell sap or animal blood (bugs, aphids, cicadas, mosquitoes, mosquitoes)
  • licking-sucking - elements of the oral apparatus have the form of tubular formations (in the form of a proboscis). It is noted in butterflies that feed on the nectar of flowers and fruit juice. In many flies, the proboscis is strongly transformed, at least five of its modifications are known, from a piercing-cutting organ in horseflies to a soft "licking" proboscis in flower flies that feed on nectar (or in carrion flies that feed on liquid parts of manure and carrion).

  Some species do not feed as adults.

  The structure of the antennae, or ties, of insects is very diverse - filiform, bristle-shaped, serrate, comb-shaped, club-shaped, lamellar, etc. Antennae one pair; they bear the organs of touch and smell, and are homologous to crustacean antennules.

  The sense organs on the antennae of insects tell them not only the state environment, they help communicate with relatives, find a suitable habitat for themselves and their offspring, as well as food. Females of many insects attract males with the help of smells. Males of the lesser nocturnal peacock eye can smell a female at a distance of several kilometers. Ants recognize by the smell of females from their anthill. Some species of ants mark their way from the nest to the source of food thanks to odorous substances that are secreted from special glands. With the help of antennae, ants and termites smell the smell left by their relatives. If both antennae capture the smell to the same extent, then the insect is on the right track. Attractant substances that are released by female butterflies ready for mating are usually carried by the wind.

• Breast insects consists of three segments (prothorax, mesothorax and metathorax), to each of which a pair of legs is attached from the ventral side, hence the name of the class - six-legged. In addition, in higher insects, the chest bears two, less often one pair of wings.

  The number and structure of the limbs are characteristic features class. All insects have 6 legs, one pair on each of the 3 thoracic segments. The leg consists of 5 sections: coxa (plow), trochanter (trochanter), femur (femur), lower leg (tibia) and jointed tarsus (tarsus). Depending on the lifestyle, the limbs of insects can vary greatly. Most insects have walking and running legs. In grasshoppers, locusts, fleas and some other species, the third pair of legs is of a jumping type; in bears that make passages in the soil, the first pair of legs is digging legs. At aquatic insects, for example, in a swimming beetle, the hind legs are transformed into rowing, or swimming.

  Digestive system presented

  • The anterior intestine, starting from the oral cavity and subdividing into the pharynx and esophagus, the posterior section of which expands, forming a goiter and chewing stomach (not in all). In consumers of solid food, the stomach has thick muscular walls and carries chitinous teeth or plates from the inside, with the help of which food is crushed and pushed into the middle intestine.

    The salivary glands (up to three pairs) also belong to the foregut. The secret of the salivary glands performs a digestive function, contains enzymes, moistens food. In bloodsuckers, it contains a substance that prevents blood clotting. In bees, the secret of one pair of glands is mixed in the crop with flower nectar and forms honey. In worker bees, the salivary glands, the duct of which opens into the pharynx (pharyngeal), secrete special protein substances ("milk"), which are used to feed the larvae that turn into queens. In caterpillars of butterflies, larvae of caddisflies and hymenoptera, the salivary glands are transformed into silk-secreting or spinning glands, producing a silky thread for making a cocoon, protective formations, and other purposes.

  • The middle intestine on the border with the foregut is covered from the inside with glandular epithelium (pyloric outgrowths of the intestine), which secrete digestive enzymes (the liver and other glands are absent in insects). Absorption of nutrients occurs in the midgut.
  • The hindgut receives undigested food residues. Here, water is sucked out of them (this is especially important for desert and semi-desert species). The posterior intestine ends with an anus, which leads out excrement.

  

  excretory organs represented by malpighian vessels (from 2 to 200), which have the form of thin tubules that flow into the digestive system at the border between the middle and hind intestines, and the fat body, which performs the function of "accumulation kidneys". The fat body is a loose tissue located between the internal organs of insects. Has a whitish, yellowish or greenish color. Fat body cells absorb metabolic products (salts of uric acid, etc.). Further, the excretion products enter the intestines and, together with the excrement, are excreted. In addition, the cells of the fat body accumulate spare nutrients- fats, proteins and carbohydrate glycogen. These reserves are spent on the development of eggs during wintering.

  Respiratory system- trachea. This is a complex branching system of air tubes that directly deliver oxygen to all organs and tissues. On the sides of the abdomen and chest there are most often 10 pairs of spiracles (stigmas) - holes through which air enters the trachea. From the stigmas, large main trunks (tracheas) begin, which branch into smaller tubes. In the chest and anterior part of the abdomen, the trachea are expanded and form air sacs. Tracheae permeate the entire body of insects, braid tissues and organs, enter inside individual cells in the form of the smallest branches - tracheoles, through which gas exchange takes place. Carbon dioxide and water vapor are removed to the outside through the tracheal system. Thus, the tracheal system replaces the functions of the circulatory system in supplying tissues with oxygen. The role of the circulatory system is reduced to the delivery of digested food to the tissues and the transfer of decay products from the tissues to the excretory organs.

  Circulatory system in accordance with the characteristics of the respiratory organs, it is relatively poorly developed, not closed, consists of a heart and a short, unbranched aorta extending from the heart to the head. A colorless liquid containing white blood cells circulating in the circulatory system is called, in contrast to blood, hemolymph. It fills the body cavity and the spaces between organs. The heart is tubular, located on the dorsal side of the abdomen. The heart has several chambers capable of pulsating, each of which opens a pair of holes equipped with valves. Through these openings, blood (hemolymph) enters the heart. The pulsation of the chambers of the heart is caused by the contraction of special pterygoid muscles. Blood moves in the heart from the posterior end to the anterior, then enters the aorta and from it into the head cavity, then washes the tissues and pours through the cracks between them into the body cavity, into the spaces between the organs, from where it enters the heart through special openings (ostia). The blood of insects is colorless, or greenish-yellow (rarely red).

  Nervous system reaches an exceptionally high level of development. It consists of the supraoesophageal ganglion, circumoesophageal connectives, suboesophageal ganglion (it was formed as a result of the fusion of three ganglia) and the ventral nerve cord, which in primitive insects consists of three thoracic ganglia and eight abdominal ones. In higher groups of insects, neighboring nodes of the ventral nerve chain merge by combining three thoracic nodes into one large node or abdominal nodes into two or three or one large node (for example, in real flies or horn beetles).

  The supraesophageal ganglion, which is often called the brain, is especially complex. It consists of three sections - anterior, middle, posterior and has a very complex histological structure. The brain innervates the eyes and antennae. In its anterior section, the most important role is played by such a structure as mushroom bodies - the highest associative and coordinating center of the nervous system. The behavior of insects can be very complex, has a pronounced reflex character, which is also associated with a significant development of the brain. The subpharyngeal node innervates the oral organs and the anterior intestine. The thoracic ganglia innervate the organs of movement - the legs and wings.

  Insects are characterized by very complex forms of behavior, which are based on instincts. Particularly complex instincts are characteristic of the so-called social insects - bees, ants, termites.

  sense organs reach an exceptionally high level of development, which corresponds to high level general organization of insects. Representatives of this class have organs of touch, smell, sight, taste and hearing.

  All sense organs are based on the same element - the sensilla, consisting of one cell or a group of sensitive receptor cells with two processes. The central process goes into the central nervous system, and the peripheral - to the outer part, represented by various cuticular formations. The structure of the cuticular sheath depends on the type of sensory organs.

  The organs of touch are represented by sensitive hairs scattered throughout the body. The organs of smell are located on the antennae and mandibular palps.

  The organs of vision play a leading role for orientation in the external environment, along with the organs of smell. Insects have simple and compound (faceted) eyes. Compound eyes are made up of a huge number of individual prisms, or ommatidia, separated by an opaque layer. This structure of the eyes gives "mosaic" vision. Higher insects have color vision (bees, butterflies, ants), but it differs from human vision. Insects perceive mainly the short-wavelength part of the spectrum: green-yellow, blue and ultraviolet rays.

  Reproductive organs are in the abdomen. Insects are dioecious organisms, they have well-defined sexual dimorphism. Females have a pair of tubular ovaries, oviducts, accessory sex glands, a seminal receptacle, and often an ovipositor. Males have a pair of testes, vas deferens, ejaculatory canal, accessory sex glands and copulatory apparatus. Insects reproduce sexually, most of them lay eggs, there are also viviparous species, their females give birth to live larvae (some aphids, botflies, etc.).

  After a certain period of embryonic development, larvae emerge from the laid eggs. Further development of larvae in insects of various orders may occur with incomplete or complete metamorphosis (Table 16).

  Life cycle. Insects are dioecious animals with internal fertilization. According to the type of postembryonic development, insects are distinguished with incomplete (in highly organized) and complete (in higher) metamorphosis (transformation). Complete metamorphosis includes egg, larva, pupa and adult stages.

  In insects with incomplete transformation a young individual emerges from the egg, similar in structure to an adult insect, but differing from it in the absence of wings and the underdevelopment of the genital organs - the nymph. Often they are called larvae, which is not entirely accurate. Its habitat conditions are similar to adult forms. After several links, the insect reaches its maximum size and turns into adult form- imago.

  In insects with complete transformation, larvae emerge from eggs, which differ sharply in structure (have a worm-like body) and in habitat from adult forms; thus, the mosquito larva lives in water, while the imaginal forms live in the air. The larvae grow, go through a series of stages, separated from each other by molts. At the last molt, an immobile stage is formed - the pupa. The pupae do not feed. At this time, metamorphosis occurs, the larval organs undergo decay, and adult organs develop in their place. Upon completion of metamorphosis, a sexually mature winged individual emerges from the pupa.

  Tab 16. Development of insects	Type of development
  	Superorder I. Insects with incomplete metamorphosis	Superorder 2. Insects with complete metamorphosis
  Number of stages	3 (egg, larva, adult)	4 (egg, larva, pupa, adult)
  Larva	Looks like an adult insect external structure, lifestyle and nutrition; smaller, wings absent or incompletely developed	Differs from an adult insect in external structure, lifestyle and nutrition
  chrysalis	Absent	Available (histolysis of larval and histogenesis of adult tissues and organs occurs in the immobile pupa)
  Detachment	Order Orthoptera (Orthoptera)	Squad of hard-winged, or beetles (Coleoptera) Order Lepidoptera, or butterflies (Lepidoptera) Order Hymenoptera (Hymenoptera)

  Class Overview

  The class of insects is divided into more than 30 orders. The characteristics of the main units are given in table. 17.

  Beneficial insects

  Honey bee or domestic bee [show] A family usually lives in a hive, which consists of 40-70 thousand bees, of which one is a queen, several hundred male drones, and all the rest are worker bees. The uterus is larger than the rest of the bees, it has well-developed reproductive organs and the ovipositor. Every day, the uterus lays from 300 to 1000 eggs (on average, this is 1.0-1.5 million in a lifetime). Drones are slightly larger and thicker than worker bees, they do not have wax glands and the queen. Drones develop from unfertilized eggs. Worker bees are underdeveloped females unable to reproduce; their ovipositor has turned into an organ of defense and attack - a sting. The sting consists of three sharp needles, between them there is a channel for removing the poison formed in a special gland. In connection with feeding on nectar, the gnawing mouth organs have changed significantly; when eating, they form a kind of tube - a proboscis, through which nectar is absorbed with the help of the muscles of the pharynx. The upper jaws are also used to build combs and other construction works. Nectar is collected in an enlarged goiter and turns into honey there, which the bee regurgitates into the cells of the honeycomb. There are numerous hairs on the head and chest of the bee, when the insect flies from flower to flower, pollen sticks to the hairs. The bee cleans pollen from the body, and it accumulates in the form of a lump, or pollen, in special recesses - baskets on the hind legs. The bees drop pollen into the cells of the honeycomb and fill it with honey. Perga is formed, with which the bees feed the larvae. On the last four segments of the bee's abdomen are wax glands, which outwardly look like light spots - mirrors. Wax comes out through the pores and solidifies in the form of thin triangular plates. The bee chews these plates with its jaws and builds honeycomb cells from them. The wax glands of the worker bee begin to secrete wax on the 3rd-5th day of its life, reach their maximum development on the 12th-28th day, then decrease and regenerate. In the spring, worker bees begin to collect pollen and nectar, and the queen lays one fertilized egg in each cell of the honeycomb. Three days later, the eggs hatch into larvae. Worker bees feed them for 5 days with "milk" - a substance rich in proteins and lipids, which is secreted by the maxillary glands, and then with bee bread. A week later, inside the cell, the larva weaves a cocoon and pupates. After 11-12 days, a young worker bee flies out of the pupa. For several days she does various work inside the hive - cleans the cells, feeds the larvae, builds combs, and then begins to fly out for a bribe (nectar and pollen). In slightly larger cells, the uterus lays unfertilized eggs, from which drones develop. Their development lasts several days longer than the development of worker bees. The uterus lays fertilized eggs in large cells-queuing cells. From them larvae hatch, which bees feed all the time with "milk". These larvae develop into young queens. Before the young queen emerges, the old one tries to destroy the mother liquor, but the worker bees prevent her from doing so. Then the old queen with a part of the worker bees flies out of the hive - swarming occurs. A swarm of bees is usually transferred to a free hive. The young queen flies out of the hive along with the drones, and after fertilization returns. The bees have a well-developed supra-pharyngeal ganglion, or brain, it is distinguished by a strong development of mushroom-shaped, or stalked, bodies, with which the complex behavior of bees is associated. Having found flowers rich in nectar, the bee returns to the hive and begins to describe figures resembling the number 8 on the combs; her abdomen oscillates. This kind of dance signals to other bees in which direction and at what distance the bribe is located. The complex reflexes and instincts that determine the behavior of bees are the result of a long historical development; they are inherited. People have been breeding bees in apiaries since ancient times. The collapsible frame hive was an outstanding achievement in the development of beekeeping; it was invented by the Ukrainian beekeeper P.I. Prokopovich in 1814. The useful activity of bees lies primarily in the cross-pollination of many plants. With bee pollination, the yield of buckwheat increases by 35-40%, sunflower - by 40-45%, cucumbers in greenhouses - by more than 50%. Bee honey - valuable food product, it is also used for therapeutic purposes in diseases gastrointestinal tract, heart, liver, kidneys. Royal jelly and bee glue (propolis) are used as medicinal preparations. In medicine, bee (wasp) venom is also used. Beeswax is widely used in various industries - electrical engineering, metallurgy, chemical production. The annual world harvest of honey is about 500 thousand tons. [show] The silkworm has been known to people for over 4 thousand years. In nature, it can no longer exist, it is bred in artificial conditions. Butterflies don't eat. Sedentary whitish female silkworms lay 400-700 eggs (the so-called grena). Of them in special rooms caterpillars are brought out on racks, which are fed with mulberry leaves. The caterpillar develops within 26-40 days; during this time she sheds four times. An adult caterpillar weaves a cocoon of silk thread, which is produced in its silk gland. One caterpillar secretes a thread up to 1000 m long. The caterpillar winds this thread around itself in the form of a cocoon, inside which it pupates. A small part of the cocoons is left alive - later butterflies hatch from them, which lay eggs. Most cocoons are killed by hot steam or exposure electromagnetic field ultra-high frequency (at the same time, the pupae inside the cocoons heat up to 80-90 ° C in a few seconds). Then the cocoons are unwound on special machines. More than 90 g of raw silk is obtained from 1 kg of cocoons.

  If it were possible to accurately calculate the harm and benefits of insects for the national economy, then perhaps the benefits would significantly exceed the losses. Insects provide cross-pollination of about 150 species of cultivated plants - garden, buckwheat, cruciferous, sunflower, clover, etc. Without insects, they would not produce seeds and would die themselves. The aroma and color of higher flowering plants have evolved as special signals to attract bees and other pollinating insects. The sanitary importance of such insects as gravedigger beetles, dung beetles, and some others is great. Dung beetles were specially brought to Australia from Africa, because without them a large amount of manure accumulated on the pastures, which prevented the growth of grass.

  Insects play a significant role in soil formation processes. Soil animals (insects, centipedes, etc.) destroy fallen leaves and other plant residues, assimilating only 5-10% of their mass. However, soil microorganisms decompose the excrement of these animals faster than mechanically crushed leaves. Soil insects, along with earthworms and other soil inhabitants, play a very important role in its mixing. Lacquer insects from India and South-East Asia secrete a valuable technical product - shellac, other species of insects - valuable natural paint carmine.

  Harmful insects

  Many species of insects damage agricultural and forest crops; up to 3,000 pest species have been registered in Ukraine alone.

  [show] Adult beetles eat young leaves of trees in spring (they eat leaves of oak, beech, maple, elm, hazel, poplar, willow, walnut, fruit trees). The females lay their eggs in the soil. The larvae feed on thin roots and humus until autumn, hibernate deep in the soil, and continue to eat roots the next spring (mainly herbaceous plants). After the second wintering in the soil, the larvae begin to feed on the roots of trees and shrubs; young plantations with an underdeveloped root system may die due to damage. After the third (or fourth) wintering, the larvae pupate. Depending on the geographic latitude of the area and climatic conditions, the development of the May beetle lasts from three to five years. [show] The Colorado potato beetle began to damage potatoes in 1865 in North America in the state of Colorado (hence the name of the pest). After the First World War, it was brought to Europe and quickly spread east to the Volga and the North Caucasus. Females lay eggs on potato leaves, 12-80 eggs per clutch. Larvae and beetles feed on leaves. For a month, a beetle can eat 4 g, a larva - 1 g of leaves. If we take into account that on average a female lays 700 eggs, then the second generation of one female can destroy 1 ton of potato leaves. The larvae pupate in the soil, and adult beetles overwinter there. In Europe, unlike North America, there are no natural enemies of the Colorado potato beetle that would restrain its reproduction. Common beet weevil [show] Adult beetles eat sugar beet seedlings in spring, sometimes completely destroying crops. The female lays her eggs in the soil, the larvae feed on the roots and root crops of sugar beets. At the end of summer, the larvae pupate in the soil, while the young beetles hibernate. Bed bug harmful turtle [show] Bed bug harms wheat, rye and other cereals. Adult bugs hibernate under fallen leaves in forest belts and shrubs. From here in April-May they fly to winter crops. At first, the bugs feed by piercing the stems with their proboscis. Then the females lay 70-100 eggs on the leaves of cereals. The larvae feed on the cell sap of the stems and leaves, later they move on to the ovaries and ripening grain. After piercing the grain, the bug secretes saliva into it, which dissolves the proteins. Damage causes drying of the grain, a decrease in its germination and a deterioration in baking qualities. [show] The front wings are light brown, sometimes almost black. They show a typical "scoop pattern", represented by a kidney-shaped, round or wedge-shaped spot, edged with a black line. The hindwings are light grey. Antennae in males slightly combed, in females filiform. Wingspan 35-45 mm. Caterpillars are earthy gray in color with a dark head. The caterpillar of the Winter scoop in autumn damages (gnaws) mainly seedlings of winter cereals (hence the name of the pest), to a lesser extent vegetable crops and root crops; in the southern regions harms sugar beets. Adult caterpillars overwinter by burrowing into the soil in fields sown with winter crops. In spring they quickly pupate. Butterflies emerging from pupae in May fly at night and at dusk. Females lay their eggs on millet and tilled crops - sugar beets, cabbage, onions, etc., and in places with sparse vegetation, so they are often attracted to plowed fields. The caterpillars destroy the sown grains, gnaw the seedlings of plants in the area of ​​the root neck, eat the leaves. Very voracious. If 10 caterpillars live on 1 m 2 of crops, then they destroy all plants and "bald spots" appear on the fields. At the end of July, they pupate, in August the second generation butterflies fly out of the pupae, which lay their eggs on weeds on stubble or winter seedlings. One female winter cutworm can lay up to 2000 eggs. In Ukraine, during the growing season, two generations of the winter cutworm develop. [show] One of our most common butterflies. The upper side of the wings is white, the outer corners are black. Males have no black spots on the front wings, females have 2 black round spots and 1 club-shaped spot on each wing. The hindwings of both males and females are the same - white, with the exception of a black wedge-shaped spot at the anterior margin. The underside of the hindwings is a characteristic yellowish-green coloration. Wingspan up to 60 mm. The body of the cabbage is covered with thick, very short hairs, giving it a velvety appearance. Variegated coloring of caterpillars is a warning about inedibility. Caterpillars are bluish-green, with yellow stripes and small black dots, the abdomen is yellow. In caterpillars of cabbage butterflies, the poisonous gland is located on the lower surface of the body, between the head and the first segment. Defending themselves, they burp a green slurry from their mouths, to which the secretions of a poisonous gland are mixed. These secretions are a caustic bright green liquid, which the caterpillars try to coat the attacking enemy with. For small birds, a dose of several individuals of these animals can be fatal. Swallowed cabbage caterpillars cause the death of domestic ducks. The people who collected these insects with bare hands happened to end up in the hospital. The skin on the hands was reddened, inflamed, the hands were swollen and itchy. Cabbage butterflies fly during the day in May-June and with a short break throughout the second half of summer and autumn. They feed on the nectar of flowers. Eggs are laid in clusters of 15-200 eggs on the underside of a cabbage leaf. In total, the butterfly lays up to 250 eggs. Young caterpillars live in groups, scrape off the pulp of cabbage leaves, older ones eat away the entire pulp of the leaf. If 5-6 caterpillars feed on a cabbage leaf, then they eat it whole, leaving only large veins. To pupate, caterpillars crawl onto surrounding objects - a tree trunk, a fence, etc. During the growing season, two or three generations of cabbage whites develop. Cabbage is common in the European part of the former USSR; this pest does not exist in Siberia, since butterflies cannot withstand severe winter frosts. The damage caused by cabbage is very great. Often, many hectares of cabbage are completely destroyed by this pest. Interesting flights of butterflies. With strong reproduction, butterflies gather in large masses and fly over considerable distances. [show] Willow borer - Cossus cossus (L.) Willow wood borer damages the bast and wood of poplars, willows, oaks, and others. deciduous trees and fruit trees. Butterflies appear in nature from the end of June, mainly in July, and depending on the geographical location, in some places even before mid-August. They fly slowly in the late evening. Summer lasts a maximum of 14 days. During the day, they sit in a characteristic pose with a slanting chest on the lower part of the trunk. Females lay eggs in groups of 15-50 pieces in cracks in the bark, in damaged places, cancerous wounds of trunks at heights up to 2 m. Caterpillars hatch after 14 days. First, the bast tissues are eaten together. On older trees with thick bark in the lower part of the trunk, the caterpillars eat out separate long, irregularly passing, oval passages in the cross section only after the first wintering. The walls of the passages are destroyed by a special liquid and are brown or black. On thinner trunks with smooth bark, caterpillars penetrate the wood earlier, usually within a month after hatching. The chips and excrement of the caterpillar are pushed out through the bottom hole. At the end of the growing season, when the leaves fall, the feeding of the caterpillars stops, which hibernate in passages until the foliage blooms, i.e. until April - May, when the caterpillars continue to feed in separate passages again until autumn, hibernate once more and finish feeding. They pupate either at the end of a circular passage, where a flight hole is prepared in advance, closed with chips, or in the ground, near a damaged trunk in a cocoon of chips. The pupal stage lasts 3-6 weeks. Before flying, the pupa, with the help of spines, protrudes halfway out of the flight hole or out of the cocoon, so that the butterfly can more easily leave the exuvium. The generation is maximum two years. The willow borer is distributed throughout Europe, mainly in the middle and southern parts. It occurs throughout the forest zone of the European part of Russia, in the Caucasus, in Siberia, as well as in Far East. Known in western and northern China and Central Asia. The front wings of the moth are gray-brown to dark gray with a "marble" pattern and blurry gray-white spots, as well as dark transverse wavy lines. The hindwings are dark brown with matte dark wavy lines. The chest is dark above, whitish towards the abdomen. The dark abdomen has light rings. The male has a wingspan of 65-70 mm, the female - from 80 to 95 mm. The abdomen of the female is terminated by a retractable, well-marked ovipositor. The caterpillar immediately after hatching is cherry-red, later - meat-red. Head and occipital shield shiny black. An adult caterpillar is 8-11 cm (most often 8-9 cm), then it is yellowish meat-colored, brown on top with a purple tint. The yellow-brown occipital shield has two dark spots. The breathing hole is brown. The egg is oval-longitudinal, light brown with black stripes, dense, 1.2 mm in size. Many insects, especially those with piercing-sucking mouthparts, carry pathogens of various diseases. Malarial Plasmodium [show] Plasmodium malaria, the causative agent of malaria, enters the human bloodstream when bitten by a malarial mosquito. Back in the 30s of the XX century. in India, more than 100 million people fell ill with malaria every year; in the USSR in 1935, 9 million malaria cases were registered. In the last century, malaria was eradicated in the Soviet Union; in India, the incidence has dropped sharply. The center of incidence of malaria has moved to Africa. Theoretical and practical recommendations for the successful fight against malaria in the USSR and neighboring countries were developed by VN Beklemishev and his students. The nature of damage to plant tissues depends on the structure of the oral apparatus of the pest. Insects with gnawing mouthparts gnaw or eat away sections of the leaf blade, stem, root, fruit, or make passages in them. Insects with piercing-sucking mouthparts pierce the integumentary tissues of animals or plants and feed on blood or cell sap. They cause direct harm to a plant or animal, and also often carry pathogens of viral, bacterial and other diseases. Annual losses in agriculture from pests amount to about 25 billion rubles, in particular, the damage from harmful insects in our country annually averages 4.5 billion rubles, in the USA - about 4 billion dollars. Dangerous pests of cultivated plants in the conditions of Ukraine include about 300 species, in particular, beetles, larvae of click beetles, mole cricket, grain bugs, Colorado potato beetle, common beet weevil, turtle bugs, meadow and stem moths, winter and cabbage scoops , hawthorn, gypsy moth, ringed moth, apple codling moth, American white butterfly, beet root aphid, etc. The fight against harmful insects To combat harmful insects, a comprehensive system of measures has been developed - preventive, including agro- and forestry, mechanical, physical, chemical and biological. Preventive measures consist in observing certain sanitary and hygienic standards that prevent the mass reproduction of harmful insects. In particular, timely cleaning or destruction of waste, garbage helps to reduce the number of flies. Drainage of swamps leads to a decrease in the number of mosquitoes. Of great importance is also the observance of the rules of personal hygiene (washing hands before eating, thoroughly washing fruits, vegetables, etc.). Agrotechnical and forestry activities, in particular the destruction of weeds, proper crop rotations, proper preparation soils, the use of healthy and sedimentary material, pre-sowing cleaning of seeds, well-organized care of cultivated plants, create unfavorable conditions for the mass reproduction of pests. Mechanical measures consist in the direct destruction of harmful insects manually or with the help of special devices: flycatchers, adhesive tapes and belts, trapping grooves, etc. In winter, wintering nests of hawthorn and goldtail caterpillars are removed from trees and burned in gardens. Physical measures - the use of some physical factors for the destruction of insects. Many moths, beetles, Diptera fly towards the light. With the help of special devices - light traps - you can timely learn about the appearance of some pests and start fighting them. To disinfect citrus fruits infected with the Mediterranean fruit fly, they are subjected to cooling. Barn pests are destroyed using high frequency currents. Therefore, integrated pest management is of particular importance, which involves a combination of chemical, biological, agrotechnical and other methods of plant protection with the maximum use of agrotechnical and biological methods. In integrated control methods, chemical treatments are carried out only in foci that threaten a sharp increase in the number of pests, and not continuous processing all areas. With the aim of protecting nature, it is envisaged that biological means of protecting plants will be widely used.

Class Insects- this is the most highly organized, numerous, diverse class of arthropods, common in all environments of life, in aquatic - secondarily. Most representatives are capable of flight. Insects belong to the phylum Arthropoda.

Meaning of insects:

1. Participation in the cycle of substances

2. Important role in food chains

3. Pollination of flowers and seed dispersal

4. Getting food, medicines, silk

5. Agricultural pests

6. Predatory insects exterminate agricultural pests

7. Damage to fabrics, wood, books, mechanisms

Class Insects

Body sections

Head, chest, abdomen

Structural features

Got wings

Habitat

In all environments

Number of walking legs

At different types-different food and different mouthparts

Respiratory system

Tracheal bundles opening on abdominal segments

Circulatory system

OPEN; blood vessels open into the cavity of the body, on the underside of the body, blood is collected in other vessels; have a heart (two-chamber - one atrium and one ventricle)

excretory system

Malpighian vessels and fat body

Nervous system

Periopharyngeal nerve ring and ventral nerve cord

In insects, the brain is the result of the fusion of clusters of nerve cells (hence more complex behavior)

sense organs

Vision (mosaic), smell, touch, hearing

Representatives

Orders Coleoptera, Scale-winged, Diptera, Hymenoptera, Orthoptera

Major orders of insects

	Representatives		oral apparatus	Type of transformation
Rigid-winged	Zhuzhe-faces, May Khrushchev, lady cow-ka	Upper - rigid (elytra), lower - flying	Gnawing type; there are carnivores and herbivores	↓ Larva (worm with three pairs of legs - caterpillar) pupa (resting stage) adult
Scale-winged	Machaon, pigeon, nettle	Two pairs covered with scales	Suction type (hobo-current); feed on plant nectar; larvae (caterpillars) have gnawing mouthparts
Two-winged	Flies, mosquitoes, gadflies, horseflies	A pair; second pair of wings modified into halteres	piercing-sucking type; feed on the blood of humans and animals
Hymenoptera	Bees, wasps, ants	Two pairs, with distinct veins	Gnawing or licking mouthparts, feed on nectar and pollen of flowers
Straight-winged	Saran-cha, grasshoppers, bear-ka	Front - with longitudinal veining, rear - fan-shaped	Gnawing mouthparts (feed on plant foods)	INCOMPLETE (larva similar to adult; growth during moult)
Bedbugs (Hemiptera)	Forest bug, berry bug, bed bug	Two pairs of wings	Piercing-sucking mouthparts
Homoptera	Aphid, copperhead	Two pairs of transparent wings	oral organs - piercing-sucking proboscis

Insects with incomplete metamorphosis

Lice, about 150		Human louse (head and clothes)
Bed bugs, over 30,000	2 pairs of wings (anterior - semi-elytra, posterior - membranous) folded flat at rest on the back. Mouth apparatus - piercing-sucking	Bed bug, water strider, harmful turtle
Orthoptera, over 20,000	2 pairs of wings (front - elytra with direct venation, back - fan membranous wings). The oral apparatus is gnawing. The hind legs are usually hopping	Common grasshopper, house cricket, locust
Dragonflies, around 4500	2 pairs of mesh wings. The body is usually elongated. The head is mobile, the eyes are very large. Mouth apparatus - gnawing	Rocker, hatch, beauty
Cockroaches, 2500	2 pairs of wings (front - leathery elytra, back - fan membranous). The oral apparatus is gnawing. Eggs are laid in a shell	Black cockroach, red cockroach, or Prussian

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A source of information: Biology in tables and diagrams. / Edition 2e, - St. Petersburg: 2004.

It is completely impossible to calculate how many insects live on Earth, but scientists are trying to establish at least an approximate number. First of all, they defined what an insect is. Insects began to be called small invertebrate arthropods. Flies, mosquitoes, moths, beetles, ants, bees, butterflies and others were assigned to this class of animals and subdivided into species. But this was not enough, since all beetles, butterflies, ants and other insects are not the same, they are very different from each other. Among all insect species, subspecies have been identified.

To date, it has been established that in total there are about 4 million various kinds insects, but scientists have determined this number approximately. How many of them actually exist, no one knows. In total, only 625,000 species were described, and that was the result of many years of painstaking work. Each of these thousands of insects had to be discovered, caught, studied, determined in what way it differs from already known species, and its distinctive features were established.

With all certainty, only one thing can be said: there are many times more species of insects on Earth than all other animals and fish. And if you try to calculate the number of all insects living on Earth in general, you get an absolutely huge figure. As far as possible, scientists are trying to solve this practically insoluble problem.

A method was developed by which it was possible to approximately count all the insects found in an area of ​​one square meter fertile moist soil. There are about 500 to 20,000 of them there. This means that about 8 million insects live in one hectare of similar soil.

Of all the insects, there are several thousand harmful ones, which scientists are trying to study better in order to find a way to deal with them.

Take, for example, the well-known flies. There are about 40 thousand of them. Among them there are harmless ones, like fruit flies, and there are those that spread pathogenic microbes or can cause death with their bites. For example, forest black flies flying in swarms are known for the fact that their bites often end in the death of people and animals. The tsetse fly, which lives in Africa, carries deadly sleeping sickness germs, even common houseflies spread many dangerous viruses such as dysentery, cholera, hepatitis, tuberculosis, typhoid, etc. The same typhoid and other infectious diseases are carried by lice and fleas.

Among poisonous spiders, a black widow spider is known, living in humid, hot places in Southern California, Chile, etc. The poison of this spider causes intestinal spasm, which causes death.

Many insects are also dangerous because they are not immediately noticed. Most insects are so small that they can only be seen under a microscope, which means that we simply do not see them when we pick up the earth or scoop up handfuls of water from a stream.

When they say about the Earth that it is a planet of people, it would be more correct to say that the Earth is a planet of insects, among which a person lives.

Where do the largest and most venomous snakes live?

There is a saying: "Fear has big eyes." The same can be said about all the legends that exist about snakes. So, they say that huge snakes live somewhere, up to 20 meters or more. But no one has actually seen such snakes and, fortunately, never will.

Experts say that the largest snake that exists on the globe is the royal python, whose length is 10 meters. This is also not a small value, but it is far from 20 meters. The royal python lives on the Malay Peninsula, Burma, Indochina and the Philippine Islands.

Python

Slightly smaller, only 7 meters, the anaconda, which lives in the tropics of South America.

The third largest is the Indian python - 6-7 meters in length. He lives in India and on the Malay Peninsula. The African rock python has about the same length. A little smaller, up to 6.5 meters long, grows a diamond python that lives in Australia and New Guinea.

For some reason, people consider the boa constrictor to be the largest snake in the world, but it is not so big and reaches only 5 meters in length. Boas live in southern Mexico, Central and South America.

And finally, the king cobra. It is considered not only one of the largest snakes (its length reaches 5.5 meters), but also the most deadly. Cobra venom is very dangerous and fast acting. It happens that people die from the bite of a king cobra within an hour.

Cobra

By the way, the longest kites are not always the heaviest. So, the royal python, the longest snake in the world, is inferior in weight to the same anaconda, which can weigh up to 160 kilograms, which is 45 kilograms more than the heaviest python.

Of all known poisonous snakes, of which there are approximately 412 species, 200 are dangerous to humans. Of these snakes, only the viper lives in Russia. Its length is not so big, only half a meter, but in India the most poisonous of the vipers lives, the length of which is one and a half meters.