Domesticated insects. Classification of insects

The silkworm (lat. Bombyx mori) is the only domesticated insect

The silkworm (lat. Bombyx mori) is an inconspicuous little butterfly with off-white wings that cannot fly at all. But it is thanks to her efforts that fashionistas around the world have been able to enjoy outfits made from beautiful soft fabric, the shine and colorful shimmer of which fascinates at first sight, for more than 5,000 years.

flickr/c o l o r e s s

Silk has always been a valuable commodity. The ancient Chinese, the first producers of silk fabric, kept their secret securely. For its disclosure there was an immediate and terrible death penalty. They domesticated silkworms back in the 3rd millennium BC, and to this day these small insects work to satisfy the whims of modern fashion.

flickr/Gustavo r..

There are monovoltine, bivoltine and multivoltine breeds of silkworm in the world. The first give only one generation per year, the second - two, and the third - several generations per year. An adult butterfly has a wingspan of 40-60 mm, it has an underdeveloped mouthparts, so it does not feed throughout its short life. The wings of the silkworm are dirty white, with brownish bands clearly visible on them.

flickr/janofonsagrada

Immediately after mating, the female lays eggs, the number of which varies from 500 to 700 pieces. The clutch of the silkworm (like all other representatives of the peacock-eye family) is called grena. It has an elliptical shape, flattened on the sides, with one side slightly larger than the other. On the thin pole there is a depression with a tubercle and a hole in the center, which is necessary for the passage of the seed thread. The size of the grenades depends on the breed - in general, Chinese and Japanese silkworms have smaller grenades than European and Persian silkworms.

flickr/basajauntxo

Silkworms (caterpillars) emerge from the eggs, and all the attention of silk producers is focused on them. They grow in size very quickly, molting four times during their lifetime. The entire cycle of growth and development lasts from 26 to 32 days, depending on the conditions of detention: temperature, humidity, food quality, etc.

flickr/Rerlins

Silkworms feed on the leaves of the mulberry tree (mulberry), so silk production is possible only in places where it grows. When the time comes for pupation, the caterpillar weaves itself into a cocoon consisting of a continuous silk thread ranging from three hundred to one and a half thousand meters long. Inside the cocoon, the caterpillar transforms into a pupa. In this case, the color of the cocoon can be very different: yellowish, greenish, pinkish or some other. True, only silkworms with white cocoons are bred for industrial needs.

flickr/JoseDelgar

Ideally, the butterfly should emerge from the cocoon on days 15-18, however, unfortunately, it is not destined to survive until this time: the cocoon is placed in a special oven and kept for about two to two and a half hours at a temperature of 100 degrees Celsius. Of course, the pupa dies, and the process of unwinding the cocoon is greatly simplified. In China and Korea, fried dolls are eaten; in all other countries they are considered just “production waste.”

flickr/Roger Wasley

Sericulture has long been an important industry in China, Korea, Russia, France, Japan, Brazil, India and Italy. Moreover, about 60% of all silk production occurs in India and China.

History of silkworm breeding

The history of breeding this butterfly, which belongs to the family of true silkworms (Bombycidae), is associated with ancient China, a country that for many years kept the secret of making an amazing fabric - silk. In ancient Chinese manuscripts, the silkworm was first mentioned in 2600 BC, and archaeological excavations in southwestern Shanxi province yielded silkworm cocoons dating back to 2000 BC. The Chinese knew how to keep their secrets - any attempt to export butterflies, caterpillars or silkworm eggs was punishable by death.

But all secrets are revealed someday. This happened with silk production. First, a certain selfless Chinese princess in the 4th century. AD, having married the king of Little Bukhara, she brought him silkworm eggs as a gift, hiding them in her hair. About 200 years later, in 552, two monks came to the Byzantine emperor Justinian, who offered to deliver silkworm eggs from distant China for a good reward. Justinian agreed. The monks set out on a dangerous journey and returned the same year, bringing silkworm eggs in their hollow staves. Justinian was fully aware of the importance of his purchase and by a special decree ordered the breeding of silkworms in the eastern regions of the empire. However, sericulture soon fell into decline and only after the Arab conquests it flourished again in Asia Minor, and later throughout North Africa, in Spain.

After the IV Crusade (1203–1204), silkworm eggs came from Constantinople to Venice, and since then silkworms have been quite successfully bred in the Po Valley. In the XIV century. Sericulture began in the south of France. And in 1596, silkworms began to be bred for the first time in Russia - first near Moscow, in the village of Izmailovo, and over time - in the southern provinces of the empire that were more suitable for this.

However, even after Europeans learned to breed silkworms and unwind cocoons, most of the silk continued to be delivered from China. For a long time, this material was worth its weight in gold and was available exclusively to the rich. Only in the twentieth century did artificial silk somewhat replace natural silk on the market, and even then, I think, not for long - after all, the properties of natural silk are truly unique.
Silk fabrics are incredibly durable and last a very long time. Silk is lightweight and retains heat well. Finally, natural silk is very beautiful and can be dyed evenly.

Used sources.

Types of domestic insects.

Of all the known insects, humans have domesticated only the honey bee and the silkworm. When breeding bees, it was possible to have honey and wax, and when breeding silkworms, silk was possible.

Bee family.

Honeybees live in large families: wild ones in tree hollows, domestic ones in hives. Each family has a female - the queen, several hundred males - drones (they live from the time they emerge from the pupae until autumn) and up to 70 thousand worker bees. The queen bee is the largest bee in the family. Starting in spring, she lays eggs (up to 2000 per day). Drones are medium-sized bees with large eyes touching at the back of the head. They fertilize the uterus. Worker bees do all the work in the hive. They are smaller than the rest of the family.

Features of the structure and behavior of worker bees.

On the underside of the worker bee's abdomen there are smooth areas called speculum. Wax is released onto their surface. Bees make hexagonal cells from it - honeycombs: large, medium and small. On the hind legs of bees there is one “basket” and one “brush”. With their help, they collect flower pollen. Having arrived at the hive, the bees place it in the cells of the honeycomb. Other worker bees compact the pollen and soak it in honey. Bee bread is formed - a supply of protein feed. The bees regurgitate the nectar collected from flowers into cells from the honey crop. Here it turns into honey - a supply of sugary food. “Milk” is produced in special glands of worker bees. They feed the queen and larvae with it. At the end of the abdomen of worker bees there is a retractable serrated sting associated with a poison gland and used for protection.

Worker bees also perform other work: ventilate the hive, clean it, seal the cracks, etc. Each of them goes through all types of activities during its life as it develops certain glands.

Bee development.

The uterus lays fertilized eggs in large and small cells, and unfertilized eggs in medium cells. The worker bees feed the larvae hatched from the eggs with “milk”. Then only the larvae of large cells receive the “milk”, the rest receive pollen and honey. After the last molt of the larvae, the worker bees seal the cells with wax. Soon the larvae pupate, and then adult insects emerge from the pupae. They gnaw through the wax caps and crawl out to the surface of the honeycomb. Queens emerge from large cells, drones emerge from medium cells, and worker bees emerge from small cells.

Silkworm.

The silkworm is a medium-sized white butterfly. Before pupation, its caterpillars weave cocoons from silk thread. Silkworm breeding began in China about 5 thousand years ago. In the process of domestication from generation to generation, butterflies were left for breeding, which laid many eggs and had underdeveloped wings, and their caterpillars wove large cocoons (their thread became up to 1000 m long or more).

Over the past decades, various breeds of silkworms have been developed, differing in the size of the cocoons, their color, length and strength of the thread.

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» Arthropods » Beneficial insects

Insects, like all living organisms without exception, play an important role in nature. Representatives of this superclass (both large beetles and tiny flies) exist everywhere and take their place in the biosphere. There are practically no places on Earth where they are not at least one, or even several, important links in the food chain. Some insects eat plants, some eat their own kind, but both the first and second serve as food for larger animals. From this point of view, tiny arthropods are no less significant elements of the fauna than, for example, animals or fish.

We should not forget that insects pollinate flowering plants, and this is the primary basis for the functioning of most of the world's flora. What is a person? What does he get from beetles, butterflies, ants, grasshoppers and the like? It turns out that insects take an active part in our lives.

Domesticated insects

Throughout his existence, man has constantly domesticated animals, in particular those that were of obvious benefit to him, were easily kept in captivity and were amenable to training. Such pets are found among mammals, birds and even fish. Insects are not left out either: the honey bee and the silkworm are domesticated. True, these species are practically the only ones. Apart from them, the only people that come to mind are the inhabitants of exotariums and various exhibitions (stick insects, strange beetles and other tropical six-legged creatures), but it is a stretch to consider them domesticated.

In the service of man

Even if we leave aside the production of silk and the storehouse of products that the striped workers of the hives provide, the benefits of insects for humans are still undeniable. Pollination and its importance for wildlife have already been mentioned above, but it is obvious that this phenomenon is no less important for cultivated plants, and therefore for global agriculture and the economy as a whole. In addition, since some representatives of the superclass are pests, then in the fight against them, who, if not their potential enemies (carnivorous species), will become the most formidable weapon? It is for these purposes that, for example, the odorous beetle (Calosoma sycophanta), ichneumon wasps and other predators are used. Cochineal mealybugs (Dactylopius coccus) are no less valuable - the dye carmine is extracted from them, as well as dried borers, click beetles and some other beetles - they are used to make jewelry. Finally, we should not forget that many insects can be eaten.

Refer to Figures 166, 167, 171 to see the structural features of the honey bee and the silkworm. How are these insects useful?

Types of domesticated insects. Of all the known insects, humans have domesticated only the honey bee and the silkworm. Bees began to be bred for honey and wax, and silkworms for silk. Subsequently, branches of the economy developed - beekeeping and sericulture.

Honey bee. This insect lives in large families: wild - in tree hollows, domestic - in hives. Each family has a female - the queen, several hundred males - drones and up to 70 thousand worker bees (Fig. 166).

The queen bee is the largest bee in the family. Starting in spring, she lays eggs day and night (up to 2000 per day). Drones are medium-sized bees with large eyes touching at the back of the head (they live in the colony from the time they emerge from the pupae until autumn). Worker bees are smaller than other family members and differ from them in a number of structural and behavioral features.

On the underside of the worker bee's abdomen there are smooth areas without hairs - speculum. Wax is released on their surface. Bees make hexagonal cells from it - honeycombs: large, medium and small. On the outer side of the hind legs of worker bees, one depression is noticeable, surrounded by long hairs. These are baskets. The hind legs also have brushes - wide segments with hard bristles (Fig. 167). With their help, bees collect adhering flower pollen from their bodies, moisten it with nectar and place it in baskets. The resulting clumps of pollen are called pollen pollen. Having arrived at the hive, the bees place them in the honeycombs. Other worker bees compact the pollen and soak it in honey. Bee bread is formed - a supply of protein feed.

Bees collect nectar from flowers in the extension of the esophagus (honey crop), and then secrete it into the cells of the honeycomb. Nectar mixed with secretions from the pharyngeal glands of a worker bee turns into honey. This creates a supply of sugary food in the hive. “Milk” is produced in special glands of worker bees. They feed it to the queen and white worm-like larvae that develop from the eggs laid by the queen.

At the end of the abdomen of worker bees there is a retractable serrated sting. This is a modified ovipositor. There is a poison gland at the base of the sting. With the help of a stinger, a bee stings its enemies. A bee that has stung a person cannot remove the stinger from his skin, and it comes off with part of the internal organs. This leads to the death of the bee.

Worker bees also do other work: ventilate the hive, clean it, and seal the cracks.

Development of bees. The uterus lays fertilized eggs in large and small cells, and unfertilized eggs in medium cells. The worker bees feed the larvae hatched from the eggs with “milk”. Then only the larvae developing in large cells receive the “milk”, the rest receive pollen and honey (Fig. 168). Queens emerge from large cells, drones emerge from medium cells, and worker bees emerge from small cells.

Swarming. Before leaving the cell, the young queen makes sounds. The old queen tries to kill her, but this is prevented by the worker bees protecting the young one.

Soon after this, the old queen leaves the nest with some of the worker bees. The emerging swarm of bees lands somewhere on a branch (Fig. 169) or at the base of a tree, and then, having found a hollow, the bees settle in it. Mating flight. The young queen emerging from the cell seeks out the sealed cells in which other queens are developing and kills them. After a few days, she flies out of the hive, rushes upward, and several dozen drones fly behind her. This is the mating flight of the female and males. After fertilization, the female returns to the hive and begins laying eggs.

Only the queen and worker bees overwinter in the apiary in hives (Fig. 170). The worker bees drive the drones out of the hive in the fall and they die.

Silkworm. The silkworm is a medium-sized white butterfly (Fig. 171). Before pupation, its caterpillars weave cocoons from silk thread, which is formed when the liquid secreted from the silk gland on the lower lip hardens.

Silkworm breeding began in China about 5 thousand years ago. In the process of domestication from generation to generation, butterflies that laid many eggs and had underdeveloped wings were left for breeding. As a result of long-term selection, female silkworms stopped flying, which made them easier to maintain. The selection of large cocoons led to the fact that their thread became long - up to 1000 m or more.

The spread of sericulture is associated with the places where the mulberry tree, or mulberry, grows, the leaves of which feed on the silkworm caterpillars. Over the past decades, various breeds of silkworms have been developed, differing in the size of the cocoons, their color, length and strength of the thread.

Female silkworms lay 300–600 eggs. The eggs are covered with a dense chitinized shell and are called grena. Caterpillars are raised on special shelves with canvas shelves. They are fed mulberry leaves.

Caterpillars grow and molt. After the fourth molt, brooms made of dry twigs - cocoon racks - are placed on the shelves. Caterpillars crawl onto them, spin cocoons and pupate.

The cocoons are collected and some of them are sent to special stations to obtain greens, while the rest are sent to factories, where they are treated with hot steam and unwound on special machines. The threads are used to make silk, and the frozen pupae are used to feed farm animals.

➊ What insects are domesticated by humans and for what purpose? ➋ What is the composition of the bee colony? ➌ What kind of work do worker bees do in a colony? ➍ What adaptations do worker bees have for collecting pollen and nectar, for building honeycombs, and for feeding larvae? ➎ In what case do queens hatch from eggs laid by a queen, and in what case do drones and worker bees hatch? ➏ What is a swarm of bees and how is it formed? ➐ What is the significance of the honey bee in nature and in human life? ➑ For what purpose are silkworms bred? ➒ What changes occurred to the silkworm during the process of domestication? ➓ How are silkworm caterpillars raised?

Using Figure 77, remember what types of animals you studied and what main classes they combine. From type to type, trace which animals developed certain organ systems and how they improved during the historical development of the animal world.

In order for 100 g of honey to be produced in a hive, a worker bee must visit about 1,000,000 flowers. A person receives from bees not only honey and wax, but also poison, royal jelly, propolis (the glue that bees use to seal the cracks in the hive), which are widely used in medicine.
In sericulture farms, 70-80 kg of cocoons are obtained from 25 g of grain.

Types of domestic insects.

Bee family.

Worker bees also perform other work: ventilate the hive, clean it, seal the cracks, etc. Each of them goes through all types of activities during its life as it develops certain glands.

Bee development.

Silkworm.

Over the past decades, various breeds of silkworms have been developed, differing in the size of the cocoons, their color, length and strength of the thread.

Articles and publications:

PIKINGDOOM MULTICELLULAR ANIMALS

TYPE ARTHROPODA

DOMESTIC INSECTS

Types of domestic insects. Since ancient times, people have been breeding certain types of insects to obtain valuable products from them. First of all, it is a honey bee, which gives humans honey, propolis, bee bread, royal jelly, and wax. Silkworm breeding for the purpose of producing natural silk is an important branch of the national economy of many countries.

Honey bee. Bees are social insects. They live in large families: wild ones in tree hollows, domestic ones in hives. Each family has a female - the queen, several hundred males - drones (they live from the time they emerge from the pupae until autumn) and up to 70 thousand worker bees. The queen bee is the largest bee in the family, whose function is to lay eggs. Starting in spring, the queen lays about 2 thousand eggs per day. Drones are medium-sized bees with large eyes that touch at the back of their heads. It is the drones that fertilize the queen. All the work in the hive is done by worker bees - underdeveloped females incapable of reproducing. They are smaller than other family members.

Features of the structure and behavior of worker bees. On the underside of the worker bee's abdomen there are smooth, hairless areas - mirrors, on the surface of which wax is secreted, from which it makes hexagonal cells - honeycombs (large, medium and small). On the hind legs of bees there is one “basket” and one “tassel” with which they collect pollen. Having arrived at the hive, the bees place it in the cells of the honeycomb. Other worker bees compact the pollen and soak it in honey. Bee bread is formed - a supply of protein feed. Bees regurgitate the nectar collected from flowers into honeycombs from the honey crop. Here it turns into honey - a supply of sugary food. “Milk” is produced in special glands of worker bees. They feed the queen and larvae with it.

At the end of the abdomen of worker bees there is a retractable serrated sting, which is connected to a poison gland and is used for protection.

In addition, worker bees ventilate the hive, clean it, seal the cracks, etc. Each of them, during its life, goes through all types of activities to the extent that certain glands develop in it.

Bee development. The queen lays fertilized eggs in large and small honeycombs, and unfertilized eggs in medium ones. The larvae that develop from eggs are fed “milk” by worker bees. Then only the larvae of large ones receive the “milk”, while others receive pollen and honey. After the last moult of the larvae, the worker bees seal the honeycombs with wax. Soon the larvae turn into pupae, and subsequently into adult insects. They gnaw through the wax caps and crawl to the surface of the wax. The large ones produce queen bees, the medium ones produce drones, and the small ones produce worker bees.

Silkworm. This is a medium-sized white butterfly. While lining, its caterpillar wraps itself with a thin thread, which is secreted by the spinning glands. By unwinding these cocoons, a person receives natural silk. Silkworm breeding began in China about 5 thousand years ago. In the process of domestication from generation to generation, butterflies were left for breeding; they laid many eggs and had underdeveloped wings, and large cocoons were woven from their caterpillars (their thread reached a length of up to 1000 m or more).

In recent decades, various breeds of silkworms have been bred, differing in the size of the cocoons, their color, length and strength of the thread.

Of all the known insects, humans have domesticated only the honey bee and the silkworm. When breeding bees, it was possible to have honey and wax, and when breeding silkworms, silk was possible.

Bee family

Honey bees

Families of honey bees can be classified as clearly social colonies. In a family, each bee performs its own function. The functions of a bee are conditionally determined by its biological age. However, as has been established, in the absence of older bees, their functions can be performed by bees of younger ages.
It is necessary to distinguish between the actual and biological age of the bee, since during the honeybee the worker bee lives from 30 to 35 days, and during wintering the bee remains biologically young for up to 9 months (Central Russian gray bee in the conditions of northern Russia and Siberia). When indicating the life span and periods of development of bees, they usually focus on the life expectancy of the bee at the time of the honeybee.

Features of the structure and behavior of worker bees. On the underside of the worker bee's abdomen there are smooth areas called speculum. Wax is released onto their surface. Bees make hexagonal cells from it - honeycombs: large, medium and small. On the hind legs of bees there is one “basket” and one “brush”. With their help, they collect flower pollen. Having arrived at the hive, the bees place it in the cells of the honeycomb. Other worker bees compact the pollen and soak it in honey. Bee bread is formed - a supply of protein feed. The bees regurgitate the nectar collected from flowers into cells from the honey crop. Here it turns into honey - a supply of sugary food. “Milk” is produced in special glands of worker bees. They feed the queen and larvae with it. At the end of the abdomen of worker bees there is a retractable serrated sting associated with a poison gland and used for protection.

Worker bees also perform other work: ventilate the hive, clean it, seal the cracks, etc. Each of them goes through all types of activities during its life as it develops certain glands. Young worker bees (up to 10 days old) make up the queen’s retinue, feeding her and the larvae, since young bees secrete royal jelly well. From approximately 7 days of age, wax glands begin to work on the lower part of the bee's abdomen and wax begins to be secreted in the form of small plates. Such bees gradually switch to construction work in the nest. As a rule, in the spring there is a massive rebuilding of white honeycombs - this is due to the fact that by this period the overwintered bees en masse reach the biological age corresponding to the rebuilding bees.

Around 14-15 days, the productivity of the wax glands drops sharply and the bees switch to the following types of nest care activities - they clean the cells, clean up and remove garbage. From the age of about 20 days, bees switch to ventilating the nest and guarding the entrance. Bees older than 22-25 days are mainly engaged in honey collection. To inform other bees about the location of nectar, the foraging bee uses visual biocommunication. Bees over 30 days old switch from honey collection to collecting water for the needs of the family. This bee life cycle is designed for the most rational utilization of nutrients and the use of the available number of bees in the family. The bee's body contains the largest amount of excess nutrients when it leaves the cell. At the same time, most bees die when they take water from natural reservoirs. Much fewer of them die when collecting honey from flowers and when approaching the hive.

Bee development. The uterus lays fertilized eggs in large and small cells, and unfertilized eggs in medium cells. The worker bees feed the larvae hatched from the eggs with “milk”. Then only the larvae of large cells receive the “milk”, the rest receive pollen and honey. After the last molt of the larvae, the worker bees seal the cells with wax. Soon the larvae pupate, and then adult insects emerge from the pupae. They gnaw through the wax caps and crawl out to the surface of the honeycomb. Queens emerge from large cells, drones emerge from medium cells, and worker bees emerge from small cells.

Silkworm

Silkworm

The silkworm belongs to the insect class, a representative of the arthropod phylum. This silkworm may be an example of a domesticated insect. As a domestic insect, people have been breeding the silkworm for several millennia; it has lost the properties of its wild ancestors and can no longer live in natural conditions. He has developed a number of adaptations that greatly facilitate his breeding. For example, silkworm butterflies have essentially lost the ability to fly. Females are especially inactive. The caterpillars are also inactive and do not crawl away.

The silkworm, like other butterflies, develops with complete transformation. The silkworm butterfly has a wingspan of 40 to 60 mm. The color of its body and wings is dirty white with more or less distinct brownish bands. By appearance, a female silkworm is quite easy to distinguish from a male. She has a more massive abdomen than the male, and her antennae are less developed. On the first day after leaving the cocoon (silk shell), the female insect lays eggs, the so-called grena. A clutch contains on average from 500 to 700 eggs. Egg laying lasts three days.

A caterpillar emerges from an egg. She grows quickly and sheds four times. Caterpillars develop within 26–32 days. The duration of their development depends on the breed, temperature, air humidity, quantity and quality of food, etc. The silkworm caterpillar feeds on mulberry leaves. At the end of development, the caterpillar strongly develops a pair of silk glands. They intensively secrete liquid, which quickly thickens in air, turning into a silk thread. From this thinnest thread, reaching 1000 m in length, the caterpillar spins a cocoon. In the cocoon, the caterpillar turns into a pupa. The co-con shell protects the pupa from various adverse conditions.

Cocoons come in different colors: pink, greenish, yellow, etc. But for industrial needs, currently only breeds with white cocoons are bred. A butterfly is formed from the pupa.

It secretes a special liquid that dissolves the sticky substance of the cocoon. With its head and legs, the butterfly pushes the silks apart and exits the cocoon through the resulting hole. Over the past decades, various breeds of silkworms have been developed, differing in the size of the cocoons, their color, length and strength of the thread.

Of all the known insects, humans have domesticated only the honey bee and the silkworm. When breeding bees, it was possible to have honey and wax, and when breeding silkworms, silk was possible.

Bee family

Honey bees

Silkworm

A caterpillar emerges from an egg. She grows quickly and sheds four times. Caterpillars develop within 26–32 days. The duration of their development depends on the breed, temperature, air humidity, quantity and quality of food, etc. The silkworm caterpillar feeds on mulberry leaves. At the end of development, the caterpillar strongly develops a pair of silk glands. They intensively secrete liquid, which quickly thickens in air, turning into a silk thread. From this thinnest thread, reaching 1000 m in length, the caterpillar spins a cocoon. In the cocoon, the caterpillar turns into a pupa. The cocoon shell protects the pupa from various unfavorable conditions.

Cocoons come in different colors: pink, greenish, yellow, etc. But for industrial needs, currently only breeds with white cocoons are bred. A butterfly is formed from the pupa. It secretes a special liquid that dissolves the sticky substance of the cocoon. With its head and legs, the butterfly pushes the silks apart and exits the cocoon through the resulting hole. Over the past decades, various breeds of silkworms have been developed, differing in the size of the cocoons, their color, length and strength of the thread.