Entomologists usually love their work for the diversity of the studied material and the abundance of insects. From a purely aesthetic point of view, the truly endless variety of shapes, colors and appearance options cannot get bored.

Digging deeper, however, the world behind insect behavior and lifestyle is even more exciting. Although in many cases their lifestyle is stereotyped, sometimes it is strikingly eccentric.

Public insects

Although many insects are solitary, some species live in large and complex communities that outwardly resemble an idealized model of human society, where their members play different roles aimed at the prosperity of the colony. However, in social insects, members of the colony are relatives. Usually there is only one female capable of breeding and an unlimited number of male capable of breeding in the entire colony. The bulk of the colony's inhabitants are sterile, and their role is limited to collecting food and defending the settlement from enemies.

Bees and wasps

Probably the most common social insects are bees and wasps. They build large nests with special compartments for raising offspring and for storing food.

Interesting fact: When a bee finds a good source of nectar and pollen and returns home, it informs the other inhabitants of the hive about it. Detailed directions and distance to the food source are conveyed through a complex bee dance.

Working bees have special pouches on their hind legs. They collect pollen from flowers and transfer it to the hive, where it is used for feeding the growing larvae.

True to their name, paper wasps build nests from chewed wood fibers that closely resemble paper. Each cell in the nest will contain an egg, and subsequently a growing wasp larva.

The queen bee is fertilized once in a lifetime, and its only task is to lay eggs thereafter for about five years. Building and repairing the hive, caring for the offspring, collecting food are only part of the responsibilities of worker bees. Each worker bee plays a different role at different times in its life. An entertaining fact - a worker bee that has found a source of nectar and pollen, returning to the hive, can inform other members of the colony about the distance and direction in which to fly, using a kind of dance.

Ants

Among those who have achieved the greatest success in social life, it should be noted that ants live, like bees, in colonies. Some worker ants collect food, others gravitate towards the care of growing larvae, and those with larger jaws become soldiers and protect the anthill. Ant colonies are divided into distinct castes, each of which plays a specific role in the generally established order. The winged queen is responsible for laying the eggs, while the smaller workers gather food.

Termites are common in the tropics. Their striking mounds, up to 6 meters high, are a classic example of daring entrepreneurship in social insects. There are four types of castes in the termite colony: the queen, the fertile males, and the sterile workers and soldiers.

Nutcrackers

Plants are an important food source for all insects, all parts of a plant, from flowers and leaves to seeds and roots, with a certain degree of probability can be eaten by, if not one insect, then another. However, not all relationships between plants and insects are so straightforward, and this is best seen in nutcrackers. These tiny insects, similar in appearance to ants, affect the plant in such a way that it develops abnormal tissue growths called galls.

Gauls serve as larvae and food and protection up to the moment of pupation. As a rule, the female gallstone lays one or more eggs (depending on the species) in the plant tissue. Each type of nutcracker is usually tied to a specific type of plant and forms galls, the size, shape and color of which are unique to this particular nutcracker. Species with a change of generations form different galls at the sexual and partheno genetic stages of the life cycle.

In some species of insects, the way of life is further complicated by the change of generations, already described earlier for aphids. First, successful mating of males and females is required, and the next generation is parthenogenetic females, producing viable offspring without the participation of males.

Walking silkworms

Caterpillars of some silkworms sometimes go on a hike in orderly rows, following each other in single file (nose to tail). Those species whose caterpillars behave in this way are called marching silkworms. The most famous of these is the pine marching silkworm from southern Europe. During the daytime, these caterpillars spend inside a large silk web, which they wrap around tree branches. Stinging hairs from the body of caterpillars can be woven into this web and, when combined with silk, be an effective defense against birds. At dusk, however, the caterpillars come out to eat. By following a single line and marking their path with silk thread, all caterpillars are able to easily find their way back home.

Moth sloths

Everyone knows three-toed sloths - slow creatures that live in the forests of Central and South America.

Each of these animals is home to up to 100 specimens of the moth, using its rough and matted fur. Every time a sloth climbs down from a tree to fulfill its natural needs on the ground, the moth lays eggs in its droppings. The caterpillars subsequently feed on this.

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Arachnids are a class of arthropods of the subtype Chelicera. The most famous representatives: spiders, scorpions, ticks, tarantulas.

Arachnids are ubiquitous.
Representatives of this class are one of the most ancient land animals, known from the Silurian period.
Nowadays, some orders are distributed exclusively in tropical and subtropical belts, such are the Storm Legs. Scorpions and bihorchs also live in the temperate zone, spiders, hay makers and ticks are also found in significant numbers in the polar countries.

Arachnids are almost exclusively predators, only a few ticks and jumping spiders feed on plant matter. All spiders are predators. They feed mainly on insects and other small arthropods. The spider grabs the caught prey with its legs, bites with hook-shaped jaws, injects poison and digestive juice into the wound. After about an hour, the spider sucks out all the contents of the prey with the help of the sucking stomach, of which only the chitinous membrane remains. This is called extraintestinal digestion.

Insects - a class or superclass of invertebrates. Refers to the incomplete type. Insects are found in almost all habitats. Insects inhabit the vast majority of known terrestrial biotopes, occupying such inhospitable ecosystems as mountaintops, deep caves, and also nascent ecosystems of newly formed islands of volcanic origin ... There are also known marine insects belonging to a special family of water striders from the order of Hemiptera (apart from them, other, typically freshwater bugs occasionally settle in coastal salt waters) .Insects are usually small in size, many of them can spend their whole life in small areas of soil, in small reservoirs, on separate parts of plants: in fruits, inside branches, on leaves, etc. Insects are content with a small amount of food. Thus, the content of one pea ensures the full development of the larva of the pea weevil beetle; the juices entering the thin root lobe of the vine are enough to feed several individuals of the phylloxera aphid; the development of the apple blossom beetle larva is completed when feeding on the pistil and stamens of only one apple bud.

At the same time, the rapid change of generations and high fertility often lead to a sharp increase in the number of individuals of some species, to their mass reproduction, and then the damage caused to cultivated plants, forests or domestic animals becomes very noticeable.

Insects, like other invertebrates (spiders, crayfish, worms, molluscs, etc.), do not have an internal skeleton. The muscles that set the body in motion are supported by compacted and sometimes very hard areas of the skin, covering the body from above and below in the form of half rings; their alternation with narrow and soft skin surfaces creates segmentation of the body, dividing it into segments. The skin of insects is both strong and elastic: it reliably, like a shell, protects the internal organs of the body and at the same time allows the animal to be flexible and mobile.

Insects are the youngest of the invertebrates and the most numerous class of animals, numbering over 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, the habitat and food sources are divided between larvae and adults. The evolutionary path of many insects is closely related to flowering plants.

More highly developed insects are winged. In the cycle of substances in nature, grave beetles, dung beetles, and consumers of plant residues play an important role, and at the same time, insects - pests of agricultural plants, gardens, food supplies, leather, wood, wool, 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 included in the Red Book of the USSR.

General characteristics of the class

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

• Head, consisting of six merged segments, distinctly detached from the chest and movably connected to it. On the head there is a pair of articulated antennae or cords, an oral apparatus and two faceted eyes; many also have one or three simple eyes.

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

  The oral apparatus consists of three pairs of limbs: upper jaws, lower jaws, lower lip (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 of the oral cavity - the tongue or hypopharynx - also belongs to the oral apparatus.

  

  

  

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

  • gnawing-chewing - elements of the oral apparatus look like short hard plates. They are noted in insects that feed on solid plant and animal food (beetles, cockroaches, orthoptera)
  • piercing-sucking - elements of the oral apparatus look like hair-like bristles elongated in length. They are noted in insects that feed on the cell sap of plants or the blood of animals (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 flower nectar and fruit juice. In many flies, the proboscis is highly transformed, at least five of its modifications are known, from a piercing-cutting organ in horseflies to a soft "licking" proboscis in flower flies feeding on nectar (or in feeding on liquid parts of manure and falling flies).

  Some species do not feed as adults.

  The structure of the antennae, or bunches, of insects is very diverse - filiform, bristle-like, serrate, comb, clavate, lamellar, etc. Antennae are one pair; they carry the organs of touch and smell, and are homologous to the antennae of crustaceans.

  The senses on the antennae of insects tell them not only the state of the environment, they help to communicate with relatives, find a suitable habitat for themselves and their offspring, as well as food. The females of many insects attract males through their smells. Males of the Lesser Night Peacock's Eye can smell the female at a distance of several kilometers. Ants recognize females from their nests by smell. Some species of ants mark their way from the nest to the food source 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 pick up the odor to the same extent, then the insect is on the right track. Attractants that are secreted by female butterflies ready to mate are usually carried away 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 carries two, less often one pair of wings.

  The number and structure of the limbs are characteristic of the class. All insects have 6 legs, one pair on each of the 3 chest segments. The leg consists of 5 sections: the basin (plow), trochanter, femur, tibia (tibia) and articulated tarsus (tarsus). Depending on the lifestyle, the limbs of insects can be very modified. Most insects have walking and running legs. In grasshoppers, locusts, fleas and some other species, the third pair of legs is of the jumping type; the bear cubs making passages in the soil have the first pair of legs - digging legs. In aquatic insects, for example, the swimming beetle, the hind legs are transformed into rowing, or swimming.

  Digestive system presented

  • The anterior gut, which begins in the oral cavity and subdivides into the pharynx and esophagus, the posterior part of which expands, forming a goiter and chewing stomach (not 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 also belong to the anterior gut (up to three pairs). The secret of the salivary glands performs a digestive function, contains enzymes, and moistens food. In bloodsucking, it contains a substance that prevents blood clotting. In bees, the secret of one pair of glands is mixed in the goiter with flower nectar and forms honey. In worker bees, the salivary glands, the duct of which opens into the pharynx (pharyngeal), secretes special protein substances ("milk"), which are fed to the larvae that turn into queens. In caterpillars of butterflies, larvae of caddis flies and hymenoptera, the salivary glands are transformed into silk-separating, or spinning glands, producing a silky thread for making a cocoon, protective formations, and other purposes.

  • The midgut at the border with the anterior gut is covered from the inside with glandular epithelium (pyloric outgrowths of the intestine), which secretes digestive enzymes (the liver and other glands are absent in insects). The absorption of nutrients occurs in the midgut.
  • The hind gut receives undigested food debris. Here water is sucked out of them (this is especially important for desert and semi-desert species). The posterior intestine ends with an anus that leads out excrement.

  

  Excretory organs are represented by malpighian vessels (from 2 to 200), which have the form of thin tubes flowing into the digestive system at the border between the middle and hind intestine, and the fatty body, which performs the function of "accumulation kidneys". The fatty body is a loose tissue located between the internal organs of insects. Has a whitish, yellowish or greenish color. The cells of the fat body absorb metabolic products (uric acid salts, etc.). Further, the products of excretion enter the intestines and, together with excrement, are excreted. In addition, the cells of the fat body store reserve nutrients - fats, proteins and the 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. Large main trunks (trachea) begin from the stigmas, which branch into smaller tubes. In the chest and anterior part of the abdomen, the trachea are dilated and form air sacs. Tracheas penetrate the entire body of insects, entwine tissues and organs, enter individual cells in the form of tiny branches - tracheoles, through which gas exchange is carried out. Carbon dioxide and water vapor are removed to the outside through the tracheal system. Thus, the tracheal system replaces the function of the circulatory system in supplying oxygen to tissues. 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 system, it is relatively poorly developed, open, consists of a heart and a short unbranched aorta extending from the heart to the head. The colorless liquid circulating in the circulatory system, containing white blood cells, is called, unlike blood, hemolymph. It fills the body cavity and the gaps between the organs. The heart is tubular, located on the dorsal side of the abdomen. In the heart there are several chambers capable of pulsating, in each of which a pair of openings, equipped with valves, open. Through these holes, 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 flows through the cracks between them into the body cavity, into the gaps between the organs, from where it enters the heart through special holes (ostia). Insect blood is colorless, or greenish-yellow (rarely red).

  Nervous system reaches an exceptionally high level of development. It consists of the supraopharyngeal ganglion, periopharyngeal connectives, the subopharyngeal ganglion (it was formed as a result of the fusion of three ganglia) and the abdominal nerve chain, which in primitive insects consists of three thoracic ganglia and eight abdominal ganglia. In the higher groups of insects, the adjacent nodes of the abdominal 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 true flies or lamellar beetles).

  The epopharyngeal 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 the mushroom bodies - the highest associative and coordinating center of the nervous system. The behavior of insects is very complex, has a clearly expressed reflex character, which is also associated with significant development of the brain. The subopharyngeal ganglion innervates the mouth organs and the anterior intestine. The pectoral 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 a high level of 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 - sensilla, consisting of one cell or a group of sensitive receptor cells with two processes. The central process goes to the central nervous system, and the peripheral process goes 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 olfactory organs 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, ant), 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 a well-expressed sexual dimorphism. Females have developed a pair of tubular ovaries, oviducts, accessory gonads, a seminal receptacle, and often an ovipositor. The males have a pair of testes, the vas deferens, the ejaculatory duct, the accessory gonads, and the copulatory apparatus. Insects reproduce sexually, most of them lay eggs, there are viviparous species, their females give birth to live larvae (part of aphids, gadflies, etc.).

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

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

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

  In insects with complete transformation, larvae emerge from eggs, which are sharply different in structure (have a worm-like body) and habitat from adult forms; for example, 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. During the last molt, a stationary stage is formed - the pupa. Pupae do not feed. At this time, metamorphosis occurs, the larval organs undergo decay, and instead of them, the organs of the imago develop. At the end of the metamorphosis, a sexually mature winged individual emerges from the pupa.

  Tab 16. Development of insects	Development type
  	Superorder I. Insects with incomplete transformation	Superorder 2. Insects with complete transformation
  Number of stages	3 (egg, larva, adult insect)	4 (egg, larva, pupa, adult insect)
  Larva	It looks like an adult insect in external structure, lifestyle and nutrition; it is smaller, the wings are absent or incompletely developed	Differs from an adult insect in external structure, lifestyle and nutrition
  Chrysalis	Missing	Yes (in the immobile pupa, histolysis of larval and histogenesis of adult tissues and organs occurs)
  Detachment	Orthoptera order (Orthoptera)	Order cruel-winged, or beetles (Coleoptera) Order Lepidoptera, or butterflies (Lepidoptera) Order Hymenoptera (Hymenoptera)

  Class overview

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

  Beneficial insects

  Honeybee, or domestic, bee [show] A family usually lives in the 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 queen bee is larger in size than the rest of the bees, she has well-developed reproductive organs and ovipositor. Every day, the uterus lays from 300 to 1000 eggs (on average, this is 1.0-1.5 million for a lifetime). Drones are slightly larger and thicker than worker bees, and they do not have wax glands either. Drones develop from unfertilized eggs. Worker bees are underdeveloped females unable to reproduce; their ovipositor has become 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 the feeding of nectar, the gnawing mouth organs have changed significantly; when they eat, 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 for honeycomb construction and other construction work. The nectar is collected in an enlarged crop and turns into honey, 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 removes pollen from the body, and it accumulates in the form of a lump, or pollen, in special recesses - baskets on its hind legs. Bees drop pollen into honeycomb cells and cover it with honey. A perga is formed, which the bees feed the larvae with. On the last four segments of the bee's abdomen, there are wax glands, which outwardly look like light spots - a mirror. The 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 a working bee begin to secrete wax on the 3-5th day of its life, reach the greatest 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. After three days, larvae hatch from the eggs. The worker bees for 5 days feed them with "milk" - a substance rich in proteins and lipids, which is secreted by the maxillary glands, and then bee bread. After a week, the larva weaves a cocoon inside the cell and pupates. After 11-12 days, a young worker bee emerges from the pupa. For several days she does various work inside the hive - cleans the cells, feeds the larvae, builds honeycombs, 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 queen cells. From them larvae hatch, which the bees feed with "milk" all the time. Young queens develop from these larvae. Before the young queen leaves, the old one tries to destroy the queen bee, but the worker bees prevent her from doing it. Then the old queen with some of the worker bees flies out of the hive - swarming takes place. The swarm of bees is usually transferred to a vacant hive. The young queen flies out of the hive together with the drones, and returns after fertilization. The bees have a well-developed epopharyngeal node, or brain, it is distinguished by the strong development of mushroom, 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 on the combs begins to describe figures resembling the number 8; at the same time her abdomen fluctuates. This peculiar dance signals to other bees in which direction and at what distance the bribe is. 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 raising 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 is 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 is a valuable food product; it is also used for therapeutic purposes in diseases of the gastrointestinal tract, heart, liver, and kidneys. Royal jelly and bee glue (propolis) are used as medicinal products. Bee (wasp) venom is also used in medicine. Beeswax is widely used in various industries - electrical engineering, metallurgy, chemical production. The annual world collection 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 feed. Inactive, whitish female silkworms lay 400-700 eggs (the so-called green). Caterpillars are taken out of them in special rooms 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-secreting 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 are left alive - later butterflies hatch from them, which lay eggs. Most of the cocoons are killed by hot steam or exposure to an ultra-high frequency electromagnetic field (in this case, 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 are obtained from 1 kg of cocoons.

  If it was 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 on their own. The aroma and color of higher flowering plants developed in the course of evolution as special signals to attract bees and other pollinating insects. The sanitary significance of such insects as grave 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 pastures, which interfered with the growth of grass.

  Insects play a significant role in soil formation processes. Soil animals (insects, millipedes, etc.) destroy fallen leaves and other plant debris, assimilating only 5-10% of their mass. However, the excrement of these animals is decomposed by soil microorganisms faster than mechanically crushed leaves. Soil insects, along with earthworms and other soil inhabitants, play a very important role in mixing it. Lacquer bugs from India and Southeast Asia secrete a valuable technical product - shellac, other types of bugs - a valuable natural dye carmine.

  Harmful insects

  Many types of insects damage agricultural and forest crops; in Ukraine alone, up to 3000 species of pests have been registered.

  [show] In spring, adult beetles eat young leaves of trees (they eat leaves of oak, beech, maple, elm, hazel, poplar, willow, walnut, fruit trees). The females lay their eggs in the soil. Until autumn, the larvae feed on thin roots and humus, hibernate deep in the soil, and in the following spring continue to eat up the roots (mainly of herbaceous plants). After the second wintering in the soil, the larvae begin to feed on the roots of trees and shrubs; young stands with an underdeveloped root system may die as a result of damage. After the third (or fourth) wintering, the larvae pupate. Depending on the geographical latitude of the area and climatic conditions, the development of the May Khrushchev lasts from three to five years. [show] The Colorado potato beetle began to damage potatoes in 1865 in North America in Colorado (hence the name of the pest). After the First World War, it was introduced 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. In a month, a beetle can eat 4 g, a larva - 1 g of leaves. Considering that the average female lays 700 eggs, then already 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] In spring, adult beetles devour the seedlings of sugar beet, sometimes completely destroying the crops. The female lays eggs in the soil, the larvae feed on the roots and roots of sugar beet. At the end of summer, larvae pupate in the soil, young beetles hibernate. Bug harmful turtle [show] The bug is a harmful bug damaging wheat, rye and other cereals. Adult bugs hibernate under fallen leaves in forest belts and bushes. From here in April-May they fly to winter crops. At first, bugs feed by piercing the stems with their proboscis. Then the females lay 70-100 eggs on the leaves of the cereals. The larvae feed on the cell sap of stems and leaves, and later move to the ovaries and ripening grain. By piercing the grain, the bug secretes saliva into it, which dissolves proteins. Damage causes drying of grain, a decrease in its germination and deterioration of baking qualities. [show] The forewings are light brown, sometimes almost black. On them - a typical "scoop pattern", represented by a kidney-shaped, round or wedge-shaped spot, edged with a black line. The hind wings are light gray. Antennae in males are weakly combed, in females threadlike. Wingspan 35-45 mm. Caterpillars are earthy-gray in color, with a dark head. In autumn, the caterpillar of the winter moth damages (gnaws) mainly the seedlings of winter cereals (hence the name of the pest), to a lesser extent vegetables and root crops; in the southern regions it harms sugar beet. Adult caterpillars hibernate buried in the soil in the fields sown with winter crops. They pupate quickly in spring. The butterflies that emerged from pupae in May fly at night and at dusk. Females lay eggs on millet and row crops - sugar beets, cabbage, onions, etc. and in places with sparse vegetation, so they are often attracted to plowed fields. Caterpillars destroy the sown grains, gnaw the seedlings of plants in the area of ​​the root collar, and eat up the leaves. Very voracious. If 10 caterpillars live on 1 m 2 of crops, then they destroy all plants and "bald patches" appear in the fields. At the end of July, they pupate, in August, butterflies of the second generation emerge from the pupae, which lay their eggs on weeds on stubble or winter seedlings. One female winter moth can lay up to 2000 eggs. In Ukraine, during the growing season, two generations of the winter moth develops. [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 hind wings 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 hind wings is of a characteristic yellowish-green color. Wingspan up to 60 mm. The body of the cabbage is covered with dense, very short hairs, giving it a velvety appearance. The variegated coloring of the caterpillars is a warning about inedibility. Caterpillars are bluish-green, with yellow stripes and small black dots, the abdomen is yellow. In cabbage butterflies caterpillars, the poisonous gland is located on the lower surface of the body, between the head and the first segment. Defending themselves, they regurgitate a green gruel from their mouths, to which they also mix the secretions of the poisonous gland. This discharge is a pungent, bright green liquid, with which the caterpillars try to smear the attacking enemy. For small birds, a dose of a few of these animals can be lethal. Swallowed cabbage caterpillars are the cause of death of domestic ducks. People who collected these insects with their 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 in the afternoon 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 heaps 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, while older ones eat out all the pulp of the leaf. If 5-6 caterpillars feed on a cabbage leaf, then they eat it whole, leaving only large veins. For pupation, 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 is absent in Siberia, since butterflies cannot withstand severe winter frosts. The harm caused by cabbage is very great. Often, many hectares of cabbage are completely destroyed by this pest. The flights of butterflies are interesting. With strong breeding, butterflies gather in large masses and fly over considerable distances. [show] Willow tree borer - Cossus cossus (L.) Willow woodworm damages the bast and wood of poplars, willows, oaks, other deciduous trees and fruit species. Butterflies appear in nature from the end of June, mainly in July, and depending on the geographic location, in some places even before mid-August. They fly slowly in the late evening. The years 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, on damaged places, cancerous wounds of trunks at heights of up to 2 m. Caterpillars hatch after 14 days. First, they jointly eat away the bast tissue. On older trees with thick bark in the lower part of the trunk, the caterpillars eat out separate long, incorrectly passing, oval passages in 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. Caterpillar splinters and excrement are pushed out through the bottom opening. At the end of the growing season, when the leaves fall off, feeding of caterpillars stops, which hibernate in the passages until the period of foliage blooming, that is, 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 the circular path, where they will prepare an air hole, closed with chips, or in the ground, near the damaged trunk in a cocoon of chips. The pupal stage lasts 3-6 weeks. Before departure, 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. Generation is maximum two years. The willow tree borer is distributed throughout Europe, mainly in the middle and southern parts. It is found throughout the forest zone of the European part of Russia, in the Caucasus, in Siberia, as well as in the Far East. Known in western and northern China and Central Asia. The front wings of the butterfly are from gray-brown to dark gray with a "marble" pattern and vague gray-white spots, as well as dark transverse wavy lines. Hindwings are dark brown with matte dark wavy lines. The chest is dark from above, whitish to 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-visible ovipositor. Caterpillar is cherry-red immediately after hatching, later meat-red. The head and occipital plate are black shining. 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 plate has two dark spots. The airway is brown. The egg is oval-longitudinal, light brown with black stripes, dense, 1.2 mm in size. Many insects, especially those with a piercing-sucking mouth apparatus, carry pathogens of various diseases. Malaria plasmodium [show] Plasmodium malaria - the causative agent of malaria - enters the human bloodstream when bitten by an anopheles mosquito. Back in the 30s of the XX century. in India, over 100 million people fell ill with malaria annually; in the USSR in 1935, 9 million malaria cases were registered. In the last century, malaria was eradicated in the Soviet Union, and the incidence in India dropped sharply. The center of the 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 V.N. Beklemishev and his students. The nature of damage to plant tissues depends on the structure of the pest's oral apparatus. Insects with gnawing mouth organs gnaw off or eat away parts of the leaf blade, stem, root, fruit, or make passages in them. Insects with a piercing-sucking mouth apparatus 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, 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 Ukraine include about 300 species, in particular beetles, larvae of click beetles, bear, bread beetles, Colorado potato beetle, common beet weevil, turtle bugs, meadow and stem moths, winter and cabbage scoops , hawthorn, unpaired silkworm, ringed silkworm, apple moth, American white butterfly, beet root aphid, etc. Fight against harmful insects To combat harmful insects, a comprehensive system of measures has been developed - preventive, including agricultural and forestry, mechanical, physical, chemical and biological. Preventive measures consist in compliance with certain sanitary and hygienic standards that prevent the mass reproduction of harmful insects. In particular, timely cleaning or disposal of waste, garbage helps to reduce the number of flies. Drainage of swamps leads to a decrease in the number of mosquitoes. Compliance with the rules of personal hygiene (washing hands before eating, thoroughly washing fruits, vegetables, etc.) is also of great importance. Agrotechnical and forestry activities, in particular, weed control, correct crop rotation, correct soil preparation, the use of healthy and sedimentary material, pre-sowing seed cleaning, 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 jars, trapping grooves, etc. In winter, in the gardens, they remove from the trees and burn the wintering nests of the hawthorn and goldtail caterpillars. Physical measures - using some physical factors to kill insects. Many moths, beetles, dipterans fly into the light. With the help of special devices - light traps - you can timely find out about the appearance of some pests and begin to fight them. To disinfect citrus fruits infected with Mediterranean fruit flies, they are refrigerated. Barn pests are destroyed using high frequency currents. Therefore, integrated pest control is of particular importance, providing for a combination of chemical, biological, agrotechnical and other methods of plant protection with the maximum use of agrotechnical and biological methods. Integrated control methods provide for chemical treatments only in the outbreaks that threaten a sharp increase in the number of pests, and not a continuous treatment of all areas. With the tsnlya nature conservation provides for the widespread use of biological plant protection products.

The earth, especially in forests and fields, hides millions of insects. Each handful of forest land is home to up to a thousand Fork-tails. One square meter of land in a field can feed over 70,000 of these little wingless creatures. Many insects feed on fungi, rotten leaves and other plant and animal debris, contributing to the circulation of substances in nature. Plants serve as food for other insects, such as root aphids and beetle larvae. Predatory larvae of ground beetles, short-winged and click beetles hunt insects, earthworms and snails. Several species of beetles live in the darkness of the caves. The eyes of most of them have atrophied in the process of evolution, but their sense of touch is developed to an incredible degree. For cave beetles, the dark color of the body is not as important as for their relatives of other species, they do not need protection from harmful ultraviolet rays. Sometimes there are light yellow or reddish species. Colorless and blind is the cave grasshopper, a wingless predatory inhabitant of karst caves.

Are insects found in ice?

In summer, in the mountains, snow and glacial fleas multiply at such a rate that the snow, due to the variegated color of insects, acquires a "bloody" hue. They feed on pollen and organic particles that the wind brings.

Can insects survive in the desert?

The beetles that live in the South African Namib Desert do an excellent job of coping with the lack of moisture. Darkling beetles of the genus Lepidochim dig grooves in the sand perpendicular to the direction of the wind. When the wind brings humid air from the Atlantic, moisture settles at the edge of the groove. Other types of beetles make headstands during wet winds. Droplets of moisture roll down the body of the beetle, and he licks them off.

Extreme conditions

Some insect species adapt to incredibly harsh environmental conditions: in Java, the larvae of Dasyhelea tersa, a species of mosquito from the midge family, develop at 51 ° C. The darkling beetles Upis ceramboides, which live in North America and Siberia, can withstand temperatures of -50 ° C.

Depth record

Siberian Lake Baikal, 1620 m deep, is the deepest lake on Earth. At the very bottom, several types of insects live. The larvae of the midges Sergerttia koschowi have set a kind of record: they live at the bottom of the lake at a depth of 1360 m.

Water striders

The largest bodies of water in the world - the seas - are practically not inhabited by insects. An exception is the Halobates water strider. Like ordinary water striders living in our area, they hunt animals that have fallen into the water. Halobates can sometimes be found in a closed ocean bay.

How insects breathe underwater

Clean streams and rivers from source to mouth are the habitat of many insects. Dragonflies, mayflies, caddis flies, stoneflies and other dipterans in the early stages of development live at the bottom of streams. Stagnant water bodies such as ditches, puddles and ponds are also home to many larvae and adult insects. The larvae of mayflies, dragonflies, caddis flies and stoneflies have no breathing holes through which oxygen-saturated air could enter their body. These insects absorb oxygen dissolved in water through filamentous, leaf-like or bundle-like appendages - trachea. Underwater adult insects store air on their bodies. The swimmer is bordered - under the wings, where its respiratory openings fit. Other water beetles and bugs have a silvery container on their abdomen. The fine hairs in the airway guide the water, preventing it from moving back. Some insects, such as the water scorpion and mosquito, breathe through an air-filled tube on the surface of the body of water.

A bumblebee is an arthropod insect. It got its name from the sound it makes during flight. These insects are brightly colored, large, beautiful. They are capable of carrying a lot of pollen. What bumblebees are in nature is described in the article.

Description

The body of the insect is thick and heavy. Their wings are small and transparent. The wings do about 400 strokes per second. In the female, the head is elongated, broadly rounded at the back of the head, while in the male it is triangular and rounded. The insect bites, using its jaw for protection.

The bumblebee has a proboscis with which it collects nectar. All species can have different lengths, for example, a small earthen bumblebee has a body of 7-10 mm, and a garden one - 18-19 mm. Insects have 6 legs. The hairs that cover the body are usually black, white, yellow, orange, reddish, or gray.

Food

Where does the bumblebee live? These insects collect pollen and nectar from plants. It turns out that they are polytrophic. To feed the larvae, bumblebees use fresh nectar and honey, which they produce on their own. The second product is more liquid than the bee product, and is also light and light. It contains over 20% water.

Residence

Where do bumblebees live? They live on all continents, with the exception of Antarctica. In the Northern Hemisphere, there are more of them in temperate latitudes, and their habitat extends beyond the Arctic Circle.

Bumblebees are considered the most cold-resistant bees. They cannot survive in the hot tropics. The body temperature can be up to 40 degrees, which is associated with the rapid contraction of the chest muscles. This causes a loud buzzing sound. This is how the bumblebee gets warm. With the cessation of movement, it cools down.

Location of nests

Where do bumblebees live? The nests can be underground. Insects settle in rodent burrows and mole holes. In the minks of rodents there is a material that can insulate a bumblebee's nest - wool, dry grass. Nests can also be on the ground. Where do bumblebees live if their dwellings are on the surface? Some species live in grass, moss bumps, bird nests.

Where else do bumblebees live? Some nests are located above the ground. These can be tree hollows, birdhouses, buildings. The nests are different in shape, depending on the cavity used by the bumblebee. A ground dwelling is usually insulated with dry grass, moss, wax. They are produced by bumblebees thanks to the abdominal glands, and then with their paws they clean off thin wax strips from the belly, put them in growth, knead them and use them to sculpt everything necessary. The optimum temperature in the nests is 30-35 degrees.

In nature

Bumblebees are considered social insects. Like all bees, they live in families, which include:

1. Large breeding uterus.
2. Small worker bumblebees.
3. Males.

If there are no queens, working males lay eggs. The family lives for 1 year - from spring to autumn. It includes fewer individuals than the bee - about 100-200, but sometimes 500.

Life span

Usually, the life span of an insect is 2 weeks. They die for various reasons, including rapid wear and tear when collecting feed. Males can live no more than a month, they die after mating. In females, after fertilization, wintering begins. Then they lay eggs, feed the larvae, and then die.

Bites and aftermath

This insect is considered to be peaceful. It is not aggressive and only bites when protecting, for example, when closing the entrance to the nest. But such a bumblebee bite is weak and not harmful. Females sting in danger. The sting does not remain in the body, compared to bees, so bumblebees do not die after being bitten. But the poison causes pain, itching, redness. There may be swelling. Symptoms may persist for several days.

Insect venom is similar to bee venom, but contains fewer components that can cause a toxic reaction. For most healthy people, this is not dangerous. It is better not to allow a bumblebee bite, but if this happens, first aid should be provided:

1. Treat the painful area with an antiseptic, alcohol or soap and water.
2. Apply a cold compress.
3. Provide an abundant warm drink.
4. Eliminate itching with an antihistamine, for example, Suprastin.

At home, you can remove the effects of a bite with folk remedies. Compresses of gruel with soda, diluted in water with an aspirin or validol tablet will help. Infusions of tansy or chamomile are suitable. The crushed foliage of parsley, plantain, dandelion has a healing effect. The compresses need to be changed after 2 hours. An excellent effect is given by chopped potatoes, onions, and apples. In case of a strong bite in the neck, eyes, lips with the appearance of allergies, you should consult a doctor.

Bumblebees are considered important pollinators of meadow, forest and agricultural crops. Many insect species cross-pollinate several times faster than bees. They pollinate clover, alfalfa, legumes.

Ants are harmful to bumblebees. They can steal honey, eggs, larvae. Therefore, insects prefer to build nests above the ground, far from anthills, and also underground. Wasps and brachycoma flies can steal honey. Canopid flies are dangerous for them. Bumblebee offspring can be destroyed by caterpillars of the amophia moth butterfly.

Thus, bumblebees are unique insects that are beneficial to nature. And they can cause harm only for the purpose of self-defense.