About animals

Secrets of the Cricetidae family Full text of a scientific article on biological sciences

Pin
Send
Share
Send


Hamster family (Cricetidae) The hamster family is the largest and most mixed. Its systematics needs radical development. There are grounds for dividing hamsters into at least 3 families: hamsters, gerbils, and field voles with 3 subfamilies: voles, mole voles, and zocoridae. The family unites more than 580 species and about 100 genera. Information on biology will be given only for a negligible part of them. It is very difficult to give a characterization of such a prefabricated family, since almost all the characters are also characteristic of the murine family. The sizes of these animals range from very small to medium: body length from D) -6 to 35-50 cm, weight from 7-8 g to 3 kg. Tail - from barely visible outside to exceeding the length of the body. It is covered with either horny scales mixed with sparse hair, or hair of different densities and lengths, sometimes with a brush on the end. Legs are either of a normal “running” (ground) type, or adapted for jumping (like jerboa), or digging the ground (legs with powerful claws), or swimming (membranes between the fingers). Auricles are normal or absent. Eyes - from normal to greatly reduced. There are 3 buccal teeth (as in murine) on each side of the upper and lower jaw. Total teeth 16. The chewing surface of the buccal teeth is tuberous, in the form of transverse ridges or angular prisms bordered by enamel walls. The largest number of species of hamsters inhabits South and North America. Significantly fewer of them are in the temperate and northern parts of Eurasia, and very few are in Madagascar and Africa.

Abstract of a scientific article in biological sciences, author of a scientific work - Schmidt E.F., Surov A.V.

The history of the discovery of the species Mesocricetus auratus (golden or Syrian, ho & amp flesh), its breeding and distribution as a laboratory and domestic animal & amp. The hypothesis about the origin of this species as a tetraploid from crossing & amp; in nature of two species of this family is discussed. Cricetidae. Descriptions are given of 14 species of this family that are found on the territory of Russia and neighboring countries.

The text of the scientific work on the topic "Secrets of the Cricetidae family"

BIOMEDICINE • No. 1 2005, p. 52-66

Secrets of the Cricetidae family

E.F. Schmidt, A.V. Harsh

Scientific Center for Biomedical Technologies, Russian Academy of Medical Sciences, Moscow Scientific-Research Institute of Evolution and Ecology Problems A.N. Severtseva RAS, Moscow

The history of the discovery of the species Mevospetiv aigashvv (golden or Syrian hamster), its breeding and distribution as a laboratory and domestic animal is described. The hypothesis about the origin of this species as a tetraploid from the crossing in nature of two species of this family is discussed. Here. Descriptions of 14 species of this family living on the territory of Russia and neighboring countries are given.

Keywords: golden (Syrian) hamster, Baraba, Chinese hamster.

The hero is a child of very noble parents. His birth is preceded by various difficulties, such as abstinence, prolonged infertility, secret, due to external obstacles or prohibitions, the proximity of parents. Then animals or people of low origin save him and feed the animal female or common woman. The grown-up hero finds his noble parents and, in the end, achieves a high position and honor.

Otto Rank. "The myth of the birth of a hero"

Lived in the world and still lives the noble family Crucetidae (Hamster). And, although this family is not so ancient (by evolutionary standards, of course), it occupies a worthy place in the vast and prosperous order Rodentia (Rodents) of the powerful cohort Grilis (Talonous). Until recently, relations between the Cricetidae family and the species Homo sapiens remained, to put it mildly, quite cool, if not hostile, moving from a latent confrontation to direct aggression on the part of the latter. H. sapiens, this impudent upstart from the animal world, seized most of the planet and usurped power over it. He arbitrarily plowed up the steppes that once served as a table and shelter for the Khomyakov family, forcing the destitute to abduct a small fraction of the crop in order to feed himself and his many offspring. However, in the second

In the twentieth century, the situation began to change and the millennial enmity, although it did not die away at all, but noticeably began to decline. The true peacemaker, the messenger of love and hostage to the treacherous friendship of H. sapiens, became a modest hero, a representative of the glorious Khomyakov family, Meso-cricetus auratus - a golden hamster, better known by the nickname Syrian.

Nature or the Creator are big jokers. The story of the appearance, taming and distribution of this little animal, set out in strict accordance with scientific facts, reminds us ridiculously of the myth of the birth of a hero, which in one form or another existed at all times and among all peoples: from the myths of Sargon the First, the founder of Babylon (2800 BC) and Heracles, (Ancient Greece) before the saga of Hydrake (Sigurd, Siegfried), among the ancient Scandinavians and Germans (IX-XIII century BC). It contains all the elements of the immortal

the plot, repeatedly disseminated by the followers of Z. Freud and C. Jung, and who had time to pretty much feed the reading public (see epigraph). Judge for yourself.

In 1839, the English zoologist J.R. Waterhouse (Waterhouse) in Aleppo (Syria) described and registered a new species of hamster, calling it Cricetus auratus (golden hamster). Subsequently, it was found that it belongs to a previously unknown genus, and the golden or Syrian hamster was renamed Mesocricetus auratus.

Fig. 1. George Robert Waterhouse

However, the first mention of these hamsters appeared back in 1797 in the second (posthumous) edition of Aleppo Alexander Russell’s Nature History with additional notes from his younger brother Patrick (cited by Whitney, 1963). But for unknown reasons, the Russell brothers did not adequately formalize the discovery of a new species, so Waterhouse, who published his description in 1840, went to the discoverer’s laurels. It said the following: “This species is smaller than an ordinary hamster, it has a wonderful golden yellow color. The coat is of moderate length and very soft with a silky gloss. Legs and tail are white. The ears are medium sized. Vibrissa ("mustache") consists of dark and white hairs. " The males have a well-developed femoral gland - a pigmented spot of rough skin in the region of

ty hips, covered with hard dark-colored hairs. In females, iron is less developed and barely visible. Like all hamsters, their skin hangs freely and hides the true contour of the body.

The animal caught by Waterhouse turned out to be a female, and, as it soon became clear, was pregnant. For 40 years, the descendants of this female successfully bred, and in 1880 were taken to England, where they were bred until 1910, when the whole colony died, and the skin and skull of the venerable ancestress are still kept in the London Museum of Natural History. Oddly enough, in nature for almost a century no one has ever met golden hamsters, and among zoologists the opinion has grown that the rare species has become extinct.

Fig. 2. Syrian hamster described by Waterhouse

However, there lived at that time a scientist who believed that the Syrian hamsters did not disappear in nature and that they could still be found. His name was Saul Adler and he was a parasitologist at the Hebrew University of Jerusalem. Adler was engaged in the study of leishmaniasis, experiments were supposed to be carried out on Chinese hamsters, known as a suitable biological model for this purpose, but the hamsters stubbornly did not want to breed in the Holy Land. That's when Adler remembered the golden hamsters of Waterhouse. Cause they being

Bio-Medicine-1-2005.pmd Aoeyaoe OuoeemoaSbeemue xepiue

the indigenous people of Syria should have felt great in the local climate. He asked colleagues from the Zoological Department to catch several of these hamsters for him.

The search began with Israel Aharoni (Agagosh), a zoologist who rediscovered many species of animals that lived in the countries of the Middle East and were considered lost. The territory of Aleppo at that time was controlled by Turkey, and Aharoni, having shown considerable diplomatic talent, gained the patronage of the Turkish authorities by giving some copies from his collection to the “head of the local administration”, collecting butterflies.

Further, as is often the case in historical chronicles, "testimonies of the chroniclers" diverge. According to one version, the construction workers — the Arabs, when digging a pit, accidentally dug up a hole, on their own initiative they caught an unknown animal with cubs and gave them away completely by chance, passing by Aharoni. With all due respect to the Syrian proletarians, the version seems unlikely. What looks more convincing is the other, according to which Aharoni turned to the local sheikh with a request to contribute to the capture of living and possibly healthy hamsters. How the clever zoologist paid for the services of the Sheikh, the story is silent, in any case, the Sheikh informed his fellow tribesmen that those who catch the animals will receive a reward. Residents responded to the call with great enthusiasm, because these small creatures, among other things, caused damage to the grain. The fishing method was simple: they dug holes in the field with damaged wheat. A few hours later, at a depth of 11 feet, a female nest was excavated with 12 still blind cubs. Unfortunately, the female had to be euthanized, since, having been captured, she began to devour her offspring. Yet 9 animals survived. Upon his return, Aharoni handed the survivors

hamsters to the founder and head of the Jewish Veterinary University, Hein Ben-Me-nachin. The next morning, it turned out that 4 animals ran away. Another female was killed by a male. Among the four remaining was either one or two females. Nevertheless, the animals began to breed, and a year later the colony numbered about 150 animals.

Remembering the unfortunate fate of the first English colony of golden hamsters, Adler tried to create their laboratory populations in different countries. So, in 1931, he smuggled into England Syrian hamsters in his coat pocket. He transferred them to E. Hindley from the Zoological Association in London. In 1938, they were brought to America and gradually spread to laboratories around the world. From now on, the existence of this species, at least in captivity, was no longer threatened. We can assume that Saul Adler was the "godfather" of domesticated Syrian hamsters, Israel Aharoni was the "midwife" and Hein Ben-Menache was the "foster parent". But how was the matter with them in nature?

However, the time has come to introduce the reader to the close and distant relatives of our hero.

The Khomyakov family, like any noble family, is simply obliged to have its own family tree. Here it is - in fig. 3.

Immediately make a reservation that in this true story we will focus only on those Khomyakovs who live or lived in the vast expanses of our once immense Motherland, or, to put it differently, in Russia, neighboring countries and in adjacent territories. For the same geopolitical reason, there are no data in the determinants and taxonomy of mammals published after the collapse of the USSR

about “our former” hamsters, which suddenly turned into foreign ones, which they don’t know about.

We will not engage in thoughtful discussions about whether the Hamsters are an independent Sgievev family 10, 8 or just a subfamily of the Sgievev family 5, 1, whether it is subdivided into subgenuses or represented by separate genera, some of which are more similar to each other and others less. For researchers who use hamsters of one species or another as laboratory animals and for lovers who breed them, this is not the point.

The central trunk of the tree, mottled hamsters, is divided into two branches: the genus real hamsters (Sgieviev), represented by a single species, the common hamster, and the genus middle hamsters (Mvzoegiev), with three or four species 10, 8.

Let's start our acquaintance with the most respectable and significant (in the physical sense) family member - with an ordinary hamster (Сгіевіт эгіевїиз). It was described by Linnaeus in 1758, the first of the entire family. The largest hamster (body length up to 35 cm, tail - almost 6 cm), that is, the size of a large rat *. It has a beautiful skin, for which it sometimes suffers. The color is bright, often tricolor: the top is reddish-brown, the abdomen is black, there are white spots on the neck and sides of the head, sometimes black individuals (melanists) are found. Instead of a claw, on the first finger of the forelimbs there is a flat nail. The diploid set of chromosomes is 22. It is widespread in nature - throughout the entire steppe and forest-steppe zone of Eurasia, reaching the Yenisei in the east, but the number is low everywhere. Preferred forbs and cereal-forbs or steppe or forest-steppe. Penetrates into the forest zone through meadows and mountains to the lower border of forests. It populates forest belts, gardens, vegetable gardens. Digs deep, complex burrows, having-

Fig. 3. Family tree of the OpovMav family

up to 10 inlets. Swims well. In the fall, they sometimes make fodder migrations to harvested fields, during which they overcome considerable distances and cross large rivers, and in the spring they return back to the steppe. They are omnivorous, but for most of the year plant foods dominate the diet. A hamster is a domestic animal: it stores holes for 10-16 kg of grain in winter in special pantry chambers (which annoys farmers very much), and each variety

* All photos were taken by st.s. Research Institute of Ecology and Evolution A.N. Severtsev RAS, Ph.D. biol. sciences, A.V. Harsh

Fig. 4. Common Hamster (OpovYu opovyu)

it stores grains separately 2, 3, 8. Contact with an animal withdrawn from the natural environment, or manipulations with its carcass pose a threat to humans, since a hamster and fleas parasitizing on it can be carriers of especially dangerous diseases, such as plague and tularemia. The last remark applies to hamsters of all species and other rodents that live in the endemic natural foci of these diseases. In laboratories, it is practically not used because of the difficulty of breeding. Being tamed, it doesn’t bite over trifles, but if it snaps, it will not seem enough. With neighbors is non-life-giving, spends most of the year alone. However, nothing human, sorry, animal, is not alien to him. But, alas, in our days, even a hamster, while on vacation, in a private setting, is not immune from the attention of the ubiquitous paparratsi.

Another branch of motley hamsters is the genus medium-sized hamsters (MvioepevShi). They differ from real hamsters in smaller sizes (up to 28 cm), a very short tail and a different arrangement of light and dark spots on the head, neck and front of the body 1, 5, 8. The main character of our true story - the golden hamster belongs to this genus ( Mw $ oegіevSh $ aigaSh $), he is also Syrian, he is also an Near Asian. In the karyotype, there are 44 chromosomes.

Fig. 5. A scene from the intimate life of ordinary hamsters

Fig. 6. The wild type of the Syrian (golden) hamster (MvzoopovUz aigaYue

The range of the species originally described under this name encompassed the Balkans, Turkey, Iran, Syria, Lebanon, and possibly part of Transcaucasia, but modern taxonomy considers the species living only in Syria and the adjacent small part of Turkey as M. auratus. Prefers dry treeless highlands (up to a height of 2300 m). It eats grass, seeds, grains, roots, tubers and everything that turns up. Far from being a convinced vegetarian. The hole, the depth of which can reach 2 m, is divided into a bedroom, pantries, toilet, has up to three inlets.

His golden brothers are very similar to their brethren, the Brandt, Radde and Newton hamsters, which were described in the last decade of the 19th century. The ranges of these species are partially superimposed 1, 8.

Aoyuoyoyo Oiyoyetoaa © ёёё херійе

Brandt's hamster (Mesocricetus brandti), it is also Asia Minor, it is also Transcaucasian, rather faded and medium-sized (body length up to 15 cm).The color is predominantly yellowish or grayish-buffy, less bright than in other species of motley hamsters, the location of the spots is similar to the rest of the average hamsters. In karyotype there are 42 chromosomes, although there are forms with 44. It is widespread in the dry upland steppes of Asia Minor and Transcaucasia. Avoid wet areas. The hole usually consists of a horizontal stroke and several vertical holes with a single inlet. The nesting chamber is located approximately at a depth of 2 m. It mainly consumes plant foods and collects significant reserves for the winter.

The hamster Radde (Mesocricetus raddei), otherwise the Pre-Caucasus, otherwise the Dagestan, was initially mistaken for a variety of the Syrian hamster. Of medium-sized hamsters, it is the largest (up to 28 cm) and occupies an intermediate position in size between an ordinary hamster and a Syrian hamster, but its tail is ridiculously short - less than 1.5 cm. In animals that belonged to this species, there were 42— 44 chromosomes, that is, it was assumed that this species is distinguished by chromosomal polymorphism. However, later they began to tend to the fact that in nature there are two subspecies (and possibly independent species): actually M. Raddei and M. nigriculus. Brownish-ocher tones predominate in the classic variety, while M. nigriculus is characterized by a more contrasting color with a blackish “cheprak”.

It is found in the dry steppes of the middle belt of the mountains of the Ciscaucasia. Inhabitant of the steppes. Digs deep, complex burrows with several inlets, pantries and a whole system of vertical and horizontal moves. In spring and early summer, it feeds on grassy vegetation (clover,

Fig. 7. Hamster Radde (MvzoopovYue gabbv! Subspecies M. p1dg1oi! Iv)

clover, alfalfa, etc.) and in the fall - seeds, especially legumes, as well as root crops, which are stored in large quantities for the winter - more than 16 kg “per capita”.

Returning to the history of the golden hamster, we note that its path is dotted with continuous riddles. Zoologists were surprised to find that, although the range of this species is quite large, and the animals are by no means rare (judging by the complaints of local residents about damage and harvest), Syrian hamsters periodically seem to completely disappear and cannot be found in nature on for several years or even tens of years. And then the participants of the next expedition to study them, literally on the very first day, easily catch the required number of animals for the endless lamentations of the natives about the losses incurred due to the “damned hamsters”. To explain the mysterious disappearances and no less mysterious occurrences of this kind of mirage, Sach (8acI) put forward an original hypothesis in 1952. But before proceeding to its presentation, we must get acquainted with the next batch of relatives of the golden hamster.

On the family tree of the Khomyakov family there is a mighty branch: the hamster (Cricetulus). It is divided into three genera: Gray Hamsters (Cricetulus), Hamsters

Eversmanns (Allocricetulus) and rat-like hamsters (Tscherskia).

The last of the listed genera is represented in the fauna of Russia by one species of the same name - the rat hamster (Tscherskia triton). This is a very peculiar species in all respects, really looking more like a wild gray rat than a hamster, both in appearance and in character. The expression of the muzzle is appropriate. A meaningful look, with a kind of familiar squint, such as: “And what did you do, dear comrade, until the seventeenth year?”. Body length - up to 25 cm, tail - up to 10 cm. The color is gray-brown, the belly is whitish, the tip of the tail is often also white.

Fig. 8. Rat hamster (Tscherskia triton)

It differs from rats by the absence of clear transverse rings on the tail (sometimes they are, but weak) and the pubescence of the soles of the hind legs, and from the eastern vole by short and sparse hairs on the tail. There are 28 chromosomes in the karyotype, but there may be additional (B-chromosomes) that are not included in the diploid number. This, most likely, indicates the existence of two subspecies. This assumption is supported by the fact that rat-shaped hamsters from Northern Primorye are much larger than from Southern.

They live in Northeast China, Korea, and in the south of Primorye. Unlike other hamsters gravitate to the shores of water bodies, settling in floodplain meadows and artisanal

nikovym thickets in river valleys. Often used for housing human buildings. Burrows are relatively complex, consisting of vertical and horizontal passages, chambers and snouts. The nesting chamber is located at a depth of about 1.5 m. They feed mainly on soybeans, corn and sunflowers, seeds of wild herbs, acorns, quinoa shoots, and sometimes feed on animals - insects, bird eggs. Make reserves for the winter (up to 10 kg). Used as laboratory animals. In nature, they are often carriers of focal diseases, including tsugugamushi fever, and in Southeast Asia - plague.

Two types of hamsters from the genus Eversmanny (AІІosgіseShІzh) - the Eversmann hamster and the Mongolian hamster (A. siggaYb) - are relatively poorly understood. It is only known that the Eversmann hamsters (AІІosgіseShІZh euyet-tappi) are slightly larger (body length up to 16 cm), have a darker color in brownish or sandy-buffy tones and a dark spot on the chest.

Karyotype - 26 chromosomes. They are more numerous and live in traps (from the Volga to northern Xinjiang, including the Volga region, Southern Urals and Northern Kazakhstan) 6, 8. They prefer to settle in dry flat steppes, semi-deserts, deserts on sandy, gravelly and desert

Fig. 9. Eversman's hamster (Allocricetulus eversmanni)

saline soils, on fixed tuberous sands, in forest-steppe zones - along the edges of clefs. Adhere to areas of cereal-wormwood steppe, solonetz, deposits and outskirts of plowed massifs. They live in deep, but simply arranged burrows 1, 10. In their diet, animal feed (insects, mollusks, lizards, chicks, voles) make up a larger proportion than other hamsters and hamsters. There have been cases of attacks of eversman hamsters even on young gophers. Unfortunately, the rest of the diet consists mainly of crops, including melons.

Aggressive to relatives, however, despite their predatory inclinations, when kept in captivity in relation to humans - cute, meek, obedient creatures, true angels among hamsters. It is not clear why they are not bred as domestic or laboratory animals.

Mongolian hamsters (Allocricetulus curtatus) are smaller (up to 15 cm), lighter in color, do not have a dark spot on their chests, are small and distributed east of the Eversmanns - in Mongolia, Tuva, Qinghai and Northern Xinjiang. Karyotype

- 20 chromosomes. The lifestyle is poorly understood. A significant place in the diet is occupied by locusts.

The genus of Gray Hamsters (Cricetulus) includes three types of hamsters, of which the Barabinsky and the Gray were described by Pallas in 1773, and the Longtail - almost a hundred years later 5, 8.

The Daurian hamster (Cricetulus barabensis), also known as the Barabinsky hamster, is a small, slightly largest mouse, like other gray hamsters, a small animal (body length up to 13 cm). The tail length is not more than 1/3 of the body length. The back is light brown, with ocher and rusty tones. A black line runs along the ridge, sometimes somewhat blurred. The belly is whitish, with a white border on the ears.

Fig. 10. Daurian hamster (barabinsky) (SpesTi1iz lagabaepvv)

There are 20 chromosomes in the karyotype, but karyomorphs are found. Allocate 4 subspecies. Distributed from forest steppes to semi-deserts of the south of Western Siberia, Tuva, Transbaikalia, Mongolia, Northeast China, Primorye, Korea. Often settles on the developed lands - arable land, deposits, in residential buildings, including - in stone houses. Lives in complex burrows, often dug by animals of other species. It feeds mainly on plant foods, but also eats insects 2, 10. One of the subspecies of the Daurian hamster, Chinese, sometimes considered as a separate species (Cricetulus griseus), was the first from the Cricetidae family to be introduced as a laboratory animal in 1919 for study leishmaniasis (kala azara). This species is especially suitable for cytogenetic studies; its diploid set contains 22 chromosomes.

Breeding Chinese hamsters is not difficult, as they are easily tamed, breed throughout the year with proper care and have no unpleasant odor. They are used to study leprosy and rickettsioses, the induction of chromosomal aberrations under the influence of radiation, in the study of stress. According to the adrenal glands response to chronic stress, Chinese hamsters are more likely to be similar to other types of laboratory animals than to their closest relatives - golden hamsters,

since adipose tissue in their adrenal glands is more evenly distributed in the cortex than in the latter.

The long-tailed hamster (Cricetulus longi-caudatus) is very similar to representatives of two other species of this genus. From a Daurian hamster, it differs in the absence of a black strip along the ridge, from a gray hamster

- a longer tail (tail length equal to 1/3 of the body length or exceeds it) and a white border on the ears. He, if I may say so, is a gray gray hamster and somewhat darker in color. There are 24 chromosomes in the karyotype.

Distributed in the mountain steppes of North and North-West China, Mongolia, Tuva, Transbaikalia in the Sayan Mountains. It populates, as a rule, the rocky slopes of the foothills in the semi-desert (up to an altitude of 1900 m above sea level), low grass and wormwood-steppe. Lives both in natural shelters and in independently dug burrows with up to 6 inlets. It feeds mainly on seeds of wild plants. In small areas of habitats, the abundance is quite high, but in general the species is rather rare.

The gray hamster (Cricetulus migratorius), unlike the Daurian one, has no black strip along the ridge. It differs from a long-tailed one with a shorter tail (less than 1/3 of the body length) and the absence of a white rim on the ears. Ears are one-color, relatively large, rounded, muzzle is sharp.

Fig. 11. The hamster is gray (OpoeTiShe t1dgaTog1ie)

The color of the upper side is from dark gray, smoky gray, brownish-gray to reddish-sand. There may be a darkening on the head and on the ridge, but fuzzy, the abdomen is light.

There are 10-11 subspecies. There are 22 chromosomes in the karyotype, but probably there is a form with 24 chromosomes. Distributed from Greece to Altai and from the northern reaches of the forest-steppe to Iran and Afghanistan. On the territory of Russia it is found throughout the south of its European part (the northern border of the range passes along the Kaluga - Ryazan - Nizhny Novgorod - Kazan line) and in the steppes in the south of the Novosibirsk region. It is also found in the Caucasus, throughout Central, Minor, Western Asia, Kazakhstan, in the Pamirs (up to 4300 m above sea level). The southern border of the range passes through Afghanistan to Xinjiang, southern Mongolia 1, 2. It inhabits the plains and mountain steppes. It often spreads after a person through the moist areas of deserts and semi-deserts. The holes dug by him have a simple device, most often with two moves and one camera. He willingly settles in the abandoned burrows of other rodents and in natural shelters. Often climbs into a person’s dwellings, in the south even lives in multi-storey buildings of large cities (Ashgabat, Bishkek, Yerevan), up to attics. Able to even drive out mice from there.

It feeds mainly on the seeds of wild and cultivated plants. Constantly eats animal feed: mollusks, beetles, ants, up to phalanges and scorpions 2, 10. In Armenia, an attempt was made to breed ^. migratorius in the laboratories of Yerevan, however, the fate that befell the colony after the collapse of the USSR is unknown.

Now, after meeting with the genus of gray hamsters, you can return to the hypothesis of Sach, who was trying to unravel why he periodically disappears and from where the golden hamster reappears. He drew

Aoyouoyoyo Oiyoyetoaaёёёyo herTyo

attention to the fact that an ordinary hamster and a species of gray hamster have a diploid set of 22 chromosomes and a golden hamster - 44. The ranges of the first two species are much wider than the last, in addition, they partially overlap each other, and the Syrian distribution area the hamster is located just in the place of imposition of these areas. In addition, in evolutionary terms, the golden hamster as a species is much younger.

Comparing these three facts, Sach concluded that the Syrian hamster is a tetraploid, derived from the crossing in nature of two parent species. Since the fruit of the adultery was not adapted enough for the hardships of the struggle for existence, it dies from time to time under the influence of natural selection.

However, ordinary hamsters and some of the kind of gray hamsters with regrettable persistence indulge in forbidden love again and again. The hypothesis is witty, although somewhat frivolous. But, alas, science still does not know cases of the emergence of new species in this way and, as modern genetic studies show, Mesocricetus auratus is no exception to this rule. In addition, putting forward the hypothesis of a hybrid origin of Syrian hamsters, Satch made an unfortunate mistake.

The fact is that the Daurian hamster, also referred to in Russian as barabinous, and sometimes Chinese, as mentioned above, is called Cricetulus barabensis in Latin, and one of its varieties

- Cr. pseudogriseus (which literally means “false gray”). In English, the name of this species is “gray hamster”, which, again, literally means “gray hamster”. But Russian zoologists call the gray hamster another species - Cr. migratorius (in translation from Latin - "migrating"). One of the alleged parental species of Sech

calls Daurian, Chinese, gray, indicating as its Latin name Cg griseus and Cg barabensis. So it’s as if we are talking about a Baraba hamster. However, in his karyotype, not 22, but 20 chromosomes. But even if we assume that some isomorphic race, having a suitable number of chromosomes, is prone to amorous pranks with a different species, there are geographical inconsistencies, since although the areas of the common hamster and the Baraba hamster are adjacent to each other, the contact area occupies part of the territory of Western Siberia, but not related to Syria. At the same time, the ranges of the common hamster and the gray hamster (Cr migratorius) coincide over a considerable area, and the distribution area of ​​the golden hamster is located just in its center, in addition, there are 22 chromosomes in the gray hamster karyotype. So, apparently, Sach was referring to a gray hamster.

But regardless of whether the Syrian hamster was born as a result of the incestuous connection of two zoological species from different genera, or in a less extravagant way, it turned out to be a truly invaluable laboratory animal for biomedical experiments. This species is widely used in the study of infectious diseases: parasitological (leishmaniasis, opisthorchiasis), bacteriological and virological (poliomyelitis, Newcastle disease).

Golden hamsters suffer from caries with an appropriate diet, causing a change in the microflora of the oral cavity, so they conduct experiments in the field of dentistry. They are suitable for studying natural or induced hypothermia. The presence of a cheek bag devoid of wool is convenient for microcirculation studies. Syrian hamsters are especially useful in the study of reproduction processes, as due to an unusually short period

feeding (16 days), and thanks to the extremely clear estrous cycles in females. The histochemical lipid response of the golden hamster adrenal glands to stress effects is different from that of other laboratory animals. They also have unusual immunogenetic features, which can be very valuable when testing chemotherapeutic drugs for the treatment of human malignant tumors.

In addition to all of the above, the triumphal procession of Syrian hamsters around the world was most promoted by their natural charm. Employees of the laboratories where these animals were bred brought golden animals home, as a gift to children. There they also bred and multiplied.So, at present, the number of Syrian hamsters bred by amateurs at home significantly exceeds the number of those kept in scientific institutions. Over the past half century, several dozen mutations in the color and structure of the hair have been identified and maintained in domesticated golden hamsters.

Fig. 12. Mutant forms of the Syrian (golden) hamster

The popularity of Syrian hamsters is explained not only by their striking appearance, cleanliness and lack of an unpleasant smell, but also by their "manner of behavior". J. Darrell repeatedly wrote

that among animals, from a human point of view, there are born comedians, and very talented ones. What he said fully applies to golden hamsters. It is impossible to watch without laughing at how they fill the cheek pouches with seeds with an anxious look, unmistakably discarding empty or spoiled ones, or, hanging on a twig like on a horizontal bar, suddenly release one foot to scratch the abdomen, and then, having no strength to pull oneself up, that's all they sag more, bulging their eyes in surprise, and finally fall to the floor of the cage, like a ripe pear. After which everything is repeated from the beginning.

However, after the Syrian hamsters in the biomedical laboratories of the world, another representative of the SpseShae family, the Dzungarian little legged hamster, entered and settled there.

One of the species of the bryfoot Hamsters (Phodopus), small animals (body length up to 10 cm) with a tail protruding from the lush fur and solely fur-covered soles of the hind legs, the Dzungarian hamster was described by Pallas in 1773, and the other two by Campbell's Hamster and Roborovsky Hamster - more than 130 years later.

Djungarian hamster (Phodopus sungorus)

- a small, slightly largest mouse, an animal with a very short tail (up to 2 cm long). Brownish or ocher-gray tones predominate in the color of the upper body. A black strip runs along the ridge. The dark coloring of the back with two or three distinct protrusions protrudes into the light coloring of the sides. The muzzle is not pointed, although the front of the skull is relatively long, the ears are small. The fur is thick and lush.

Karyotype - 28 chromosomes. Distributed in the south of Western Siberia, in East Kazakhstan. There is an isolate in Khakassia. It inhabits dry plain and mountain steppes without shrubs, found in gravel

Fig. 13. Djungarian hamster (Phodopus sungorus)

steppe, although it prefers cereal-wormwood. Digs holes with branching passages, one or two chambers to a depth of 1 m. Willingly settles in the holes of other rodents, sometimes lives in a common hole with them. By winter, it accumulates subcutaneous fat, although it does not hibernate. Of all the Khomyakovs, the fur color has a clearly pronounced seasonality: in winter it becomes much brighter (up to white in the eastern part of the range). In addition to plant foods (seeds), it often eats insects and their larvae. The abundance in some places is quite high. It can carry many dangerous and especially dangerous diseases: plague, tularemia, pasteurellosis, typhoid fever 1, 5, 8, 10. It reproduces well in captivity. Widely used as a laboratory animal.

A small digression should be made here.

Of course, in biomedical laboratories, for some research, the Dzungarian hamster is indispensable, and there is nothing to be done. But in recent decades, among amateurs in Russia, it has become fashionable to keep Dzungarian hamsters as pets. Just before you start them, you should think carefully. No, they look charming, especially in winter fur: such small hamster Santa Clauses in gray fur coats with a dark stripe

on the back, with a fluffy, as if made of cotton wool, white "mustache" and "beard". But, here is their temper. In order not to slander the dumb creatures, I just note that the Universe in the view of the Dzungarian hamster consists of two main parts: one that can be bitten off, and one that can be bitten. The rest, a very insignificant part of the universe of the Dzungarian hamster does not care. We add that with their small size, these animals have quite decent and very sharp self-sharpening incisors. So, before purchasing a Djungarian hamster, a masochist-lyubitel should acquire a metal cage with a frequent net (wooden gnawed on the first night), or a glass terrarium, garden mittens and enough dressings and hydrogen peroxide.

Campbell's Hamster (Phodopus campbe Ш)

in appearance it is almost indistinguishable similar to the Dzungarian, but the color is lighter, fawn. Unlike the Dzungarian, he does not have a seasonal change in color. Species isolation from the Dzungarian hamster is proved hybridologically. Distributed in Mongolia, Tuva, Transbaikalia. Widely used in laboratories, and also bred by amateurs as a pet. On one of the sites that unites hamster lovers on the Internet, it was

Fig. 14. Campbell's Hamster (Phodopus campbe Ш)

Bio-Medicine-1-2005.pmd Aoyuoyoyo 6iooyooya® © ёtёyhertiyo

it is written that "Campbell's hamsters are somewhat meaner than the Dzungar hamsters." Hard to imagine

- however, there is no limit to perfection.

Due to the fact that Campbell's hamster was

isolated as a separate species relatively recently, terminological difficulties have arisen: hamsters of this species are sometimes also called Dzungarian or both species

- Siberian, moreover, the zoologists of the English-speaking countries name Campbell's hamsters as Djungarian or Siberian. Lovers of bony hamsters claim that sellers on the Bird Market adhere to the English interpretation (oh, this is our cringing attitude to the West!). The confusion with the names was aggravated by the following circumstances.

Campbell first introduced Khomyachkov into the laboratory practice of E.E. Poghosyants in 1965. She created and supported a colony of these animals at the Institute of Oncology of the Academy of Medical Sciences of the USSR, where for many years they were used in experiments. At that time, zoologists had not yet divided the bore hamsters into PH. Tue ^ Egive and PH. satrish, and they were called both those and others Dzungarian. Thus, the bony hamsters of this wiring are known as Dzungarian.

Under this name, they were bred in the 70s of the last century in the Stolbovaya nursery of the USSR Academy of Medical Sciences (Moscow Region) and delivered to the research institute for experiments, but in reality they were Campbell's hamsters. Actually, Dzungarian hamsters are more often used in laboratories in Western Europe and in America to study photoperiodism, since the seasonal color change of fur strongly correlates with the level of hormones and the duration of light exposure.

Roborovsky hamster (Phodopus roborov-skii) is the smallest of the bore hamsters (body length up to 9 cm, tail - about

1 cm). The upper part is painted in relatively light, pinkish-ocher tones. There is no black strip along the ridge. More

the dark color of the back protrudes into the lighter coloration of the sides, but only one protrusion is clearly pronounced.

Fig. 15. Hamster Roborovsky (Phodopus roborovskii)

There are 34 chromosomes in the karyotype. It is widespread in Mongolia and the adjacent territories of Russia (south of Tuva), Kazakhstan (Zaysan Valley) and China 8, 10. It populates sandy deserts and semi-deserts. Prefers fixed sands and sand steppes. Digs in the sand simple burrows of 1-2 moves and a nesting chamber. In the summer, clogs the inlets with sand. More active and mobile than other leggy hamsters. It feeds mainly on seeds of hodgepodge, sedge, cereals, tulips.

As a laboratory animal, it is not used, although it may be of interest for studying stress. It is bred by lovers at home, but its maintenance requires great care because of its increased sensitivity to stress, which often leads to the death of the animal.

Finally, let us recall a thin branch on the family tree of the family of hamster, mouse-like hamsters (Calo-myscus). In all honesty, these are not hamsters at all, so there are some foundlings. Perhaps the zoologists simply did not know where to stick them: the SaBuvst hamsters are not too similar, but they are even less similar to the rest of the rodents, and to separate a separate family for such crumbs is somehow

not solid. This strange genus is represented by 5-6 species.

The mouse hamster (Calomyscus bali-wardi) is a very small animal, the size of a small mouse (body length up to 8 cm). But his tail is very long, up to 10 cm, and besides, it is covered with thick wool, with a narrow brush at the end like a whisk. The muzzle is sharp, the ears are large, rounded, the hind legs are developed much better than the front. The back and sides are fawn and sand, the abdomen and legs are pure white, the tail is also two-tone: dark from above, white below.

Distributed in Balochistan, Afghanistan, Iran. On the territory of the former USSR it is noted in Turkmenistan (Kopet-dag mountains) and in the Transcaucasus (Nakhichevan). It lives among the rocks, along the talus of large stones, in gorges, caves. Norah arranges in crevices, cracks and voids among stones. It feeds mainly on seeds, nuts, and uses animal feed.

Exceptionally fast and nimble animal, perfectly climbs stones and narrow cracks. Unlike all other hamsters, he lives in close proximity to his own kind. In captivity, mouse-like hamsters are kept in groups in spacious terrariums or in enclosures with glass walls. It is difficult to convey all the beauty and grace of the movements of the flock of these animals, continuously circling in some kind of bewitching dance. It seems that they glide in the air, like a hummingbird or a bee swarm.

Summing up our acquaintance with the hamsters, we note their common family traits. Members of this family (at least those that live in the Old World) have cheek pouches that serve as containers for transporting feed. In some species, they are well developed, for example, in ordinary hamsters, in others (mouse-like hamsters) they are rudimentary. Most hamsters make decent

food reserves for the winter, sometimes clearly excessive. They do not have true hibernation, in which hypothermia is observed, the respiratory rate decreases and the body plunges into parabiosis, and the body is nourished due to the accumulated brown fat. But many species of hamsters have a more or less prolonged winter sleep with periodic awakenings or a seasonal decrease in activity.

All hamsters and hamsters live in holes, at least in certain periods of the year. Digging holes, as a rule, on their own, but, sometimes, others use it. Some of them do not hesitate to drive out the "legitimate" owners from there or live in a "communal" with animals of other species. Because of squabbling and aggressive morals, they do not form colonies (except for Chinese, borefoot and mouse-like), nor do married couples. When breeding in captivity, some types of hamsters can be kept in pairs or even in groups, but this is the result of selection.

And finally, the sacramental question: are hamsters pests? It makes no sense to deny that by their procurement activities they cause some damage to agriculture. But ecologists have long proved that there is no division into "clean" and "unclean" creatures, "useful" and "harmful" animals. In nature, hamsters play an important and constructive role, not only as a food base for rare species of predators. Hamster digging helps aeration the soil, fertilize it and build up the fertile layer.

Since hamsters almost never eat the stocks of seeds of wild herbs, stone fruits, tubers and bulbs that are completely accumulated for the winter, they contribute to their distribution in nature and, thereby, the consolidation of sand and natural “reclamation” of deserts and semi-deserts in the steppe and forest-steppe.

The main purpose of this excursion into the history of the Khomyakov family is to capture a number of simple postulates in the memory of experimenters working with laboratory animals (and this is mainly doctors).

1. At least 14 species of the subfamily Cricetinae of the family Cricetidae inhabit the territory of the former USSR and neighboring countries. In laboratory practice, hamsters and hamsters of 5 zoological species are used (Chinese, Syrian, Campbell, Dzungarian, and possibly gray). Hamsters of another species (Roborovsky) are bred by amateurs as pets.

2. Hamsters are not cubs of hamsters, but representatives of other genera that differ significantly both from the genus of hamsters and from each other.

3. The Dzhungar hamster, in the opinion of Russian zoologists, is Phodopus vyschotsh, and in the Wild West (in the USA) and in the no less wild Bird Market - Phodopus sashrvSh.

So is the Syrian hamster, in fact, a natural hybrid of two different zoological species, besides belonging to different genera? Hard to say. Romantic but unlikely. However, who can argue that Hercules was in fact the son of Zeus, Theseus - Poseidon, and Siegfried - Wotan? That is the myth.

1. Bobrinsky N.A., Kuznetsov B.A., Kuzyakin A.P. The determinant of mammals of the USSR M .: Education, 1965, p. 306-313.

2. Gromov I.M., Erbaeva M.A. Mammals of Russia and adjacent territories. Hare and rodents. SPb., 1995.

3. Gromov I.M., Polyakov I.Ya. Voles (Micro-tinae). Fauna of the USSR, mammals. L .: Nauka, 1977, 3 (8).

4. Darrell J. Under the canopy of a drunken forest. M.: Thought, 1964, p. 29.

5. Kuznetsov B.A. Key to vertebrates of the fauna of the USSR. Part 3. Mammals. M .: Education, 1975.

6. Mammals of Kazakhstan, t, 1 (3). Gerbils, voles, Altai zokor. Alma-Ata: Science, 1978.

7. Terrestrial mammals of the Far East (qualifier). M .: Nauka, 1984.

8. Pavlinov I.Ya., Rossolimo O.L. Systematics of mammals of the USSR. M.: Publishing House of Moscow State University, 1987.

9. Rank O. Myth about the birth of a hero. M .: Refl beech - Wakler, 1997, p. 168-216.

10. Flint V.E., Chugunov Yu.D., Smirin V.M. Mammals of the USSR. M.: Thought, 1970, p. 336-353.

11. Wintley R. Hamsters. In: Animals research. Ed. W. Lane-Petter. London — N.Y. Academic Press, 1963, pp. 287-321.

THE MYSTERIES OF CRICETIDAE E.F. Schmidt, A.V. Surov

Research Center for Biomedical Technologies of RAMS, Moscow A.N. Sevetsev Research Institute for Evolution and Ecology Problems

The history of Mesocricetus auratus (golden, or syrian hamster), its cultivation and distribution is related. The hypothesis about its origin by crossing two species of the Cricetidae in nature is discussed. Descriptions of 14 species of this family living on the territory of Russia and neighboring countries are given.

Key words: golden (sirian) hamster, barabiens, chinese hamster.

General about animal chromosomes

A chromosome is the structure of the nucleus of a cell in which hereditary information is stored. It is formed from a DNA molecule that contains many genes. In other words, a chromosome is a DNA molecule. Its number in different animals is not the same. So, for example, a cat has 38, and a cow has -120. Interestingly, earthworms and ants have the smallest numbers. Their number is two chromosomes, and the male of the latter - one.

In higher animals, as well as in humans, the last pair is represented by XU sex chromosomes in males and XX in females. It should be noted that the number of these molecules for all animals is constant, but in each species their number is different. For example, we can consider the content of chromosomes in some organisms: in chimpanzees - 48, crayfish -196, in the wolf - 78, hare - 48. This is due to the different level of organization of one or another animal.

On a note! Chromosomes are always arranged in pairs. Genetics claim that these molecules are the elusive and invisible carriers of heredity. Each of the chromosomes contains many genes. Some believe that the more these molecules, the more developed the animal, and its body is more complex. In this case, a person should not have 46 chromosomes, but more than any other animal.

How many chromosomes do different animals have

It is necessary to pay attention! In monkeys, the number of chromosomes is close to the value of a person. But for each species, the results are different. So, different monkeys have the following number of chromosomes:

  • Lemurs have 44-46 DNA molecules in their arsenal,
  • Chimpanzee - 48,
  • Baboons - 42,
  • Monkeys - 54,
  • Gibbons - 44,
  • Gorillas - 48,
  • Orangutan - 48,
  • Macaque - 42.

The family of canine (carnivorous mammals) has more chromosomes than monkeys.

  • So, the wolf - 78,
  • coyote - 78,
  • small fox - 76,
  • but the ordinary - 34.
  • The predatory animals of the lion and tiger have 38 chromosomes each.
  • The pet cat has 38, and his opponent’s dog has almost twice as many dogs - 78.

In mammals that are of economic importance, the number of these molecules is as follows:

  • rabbit - 44,
  • cow - 60,
  • horse - 64,
  • pig - 38.

Informative! The largest chromosome sets among animals are hamsters. They have 92 in their arsenal. Also in this row are hedgehogs. They have 88-90 chromosomes. And the smallest number of these molecules are endowed with a kangaroo. Their number is 12. It is very interesting that the mammoth has 58 chromosomes. Samples taken from frozen tissue.

For clarity and convenience, data from other animals will be presented in a summary.

Name of animal and number of chromosomes:

Spotted martens12
Kangaroo12
Yellow marsupial mouse14
Marsupial Anteater14
Common possum22
Opossum22
Mink30
American Badger32
Korsak (fox steppe)36
Tibetan fox36
Panda small36
Cat38
a lion38
Tiger38
Raccoon38
Canadian beaver40
Hyenas40
House mouse40
Baboons42
Rats42
Dolphin44
Rabbits44
Human 46
Hare48
Gorilla48
American fox50
Striped skunk50
Sheep54
Elephant (Asian, savannah)56
Cow60
Goat60
Woolly monkey62
Donkey62
Giraffe62
Mule (hybrid donkey and mare)63
Chinchilla64
Horse64
Gray fox66
White tailed deer70
Paraguayan fox74
Small fox76
Wolf (red, red, maned)78
Dingo78
Coyote78
Dog78
Jackal ordinary78
A hen78
Dove80
Turkey82
Ecuadorian hamster92
Common lemur44-60
Arctic fox48-50
Echidna63-64
Hedgehogs88-90

The number of chromosomes in different species of animals

As you can see, each animal has a different number of chromosomes. Even in representatives of the same family, indicators differ. You can consider the example of primates:

  • the gorilla has 48
  • the macaque has 42, and the monkey has 54 chromosomes.

Why this is so remains a mystery.

Video

A chromosome is a structure that contains nucleic acid and is responsible for the storage, execution and transfer of information about hereditary traits. It is based on a DNA molecule - deoxyribonucleic acid. There are two types of chromosomes:

  • eukaryotes - contain DNA molecules in the nucleus and mitochondria,
  • prokaryotes - DNA-containing structures are located in a nuclear-free cell.

The chromosomes located inside the nucleus are long chains with genetic information. A gene is a unit of heredity of living things, a stretch of DNA. Chromosomes are also called particles of heredity, they make up pairs - a person has 23, that is, all hereditary information about a person is contained in 46 particles.

The number of chromosomes in animals

In cats, the number of pairs of chromosomes is 19 and the total number of particles of heredity is 38. Each gene is responsible for a separate feature of the body, many of which interact with each other and one feature can be controlled by several genes at once, so they are difficult to study.

Cells are formed from DNA and chromosomes. . We can say that the chromosome is a DNA molecule and there are many genes in it. The number of chromosomes in different animals may be the same, for example, a pig has the same number as a cat - 38. The smallest number of particles of heredity was seen in earthworms (2). Ants are also champions in this regard: females have 2 particles, and males have 1 at all.

The last pair of chromosomes in a male person looks like XU, and in women XX. The situation is similar in higher animals, including cats and dogs. But the number of molecules for each animal species, although constant, is different in number for each organism:

  • hare - 48,
  • crayfish - 196,
  • monkey - 54,
  • cow - 60,
  • horse - 64.

Among animals, the most numerous chromosome set in hamsters (92), slightly less in hedgehogs (90). The minimum number of such molecules in a kangaroo is 12. According to samples of frozen tissue mammoth found that he had 58 chromosomes.

Particles of heredity cats

The study of heredity and the number of chromosomes is the science of genetics. The number and structure of particles of heredity in each animal species is a constant parameter and it is called a karyotype. Any deviations can provoke hereditary diseases, the appearance of inactive individuals or new species. All pairs of chromosomes, and there are 19 of them in a cat, are identical in shape and appearance. The exception is one pair , which is responsible for sexual characteristics - it has particles of heredity of different sizes: the chromosome X, which determines the female sex, is larger, and the male sex, Y, is smaller. The sex of the future individual depends on their combination during fertilization.

The information embedded in DNA is called the genotype, and the outward expression of the features is called the phenotype. All genes are paired - one from a cat and a cat. One of them is dominant, more powerful and determines the manifestation of their signs in kittens. The other is recessive, it is oppressed by the dominant and hidden on demand. And when the two recessive - from a cat and a cat, you get kittens that are not like either one or the other. For example, a white cat and a black cat may have red offspring if both recessive genes were responsible for the red color. Feline inherited symptoms are as follows:

  • dimensions and contour of the auricle, the location of the ears,
  • color of wool and length of villi,
  • pigmentation of the eyes
  • tail length and others.

Culling of defective individuals is carried out in order to maintain breed cleanliness based on the analysis of the chromosome set. It is important to keep track of deviations of the observed violations in order to try to influence the correction of anomalies by rational feeding and training of cats. Thus, it is possible to reveal oppressed genes that can affect the improvement of the breed or give impetus to the creation of a new one.

Color of wool and pupils

20 years ago map hereditary particles of a cat included only dozens of genes, and today there are already thousands of them. Among them are the units responsible for coloring, mutations in which lead to a change in the color of the coat. For example, one of the somatic particles, non-sexual, contains elements of a mutation of six colors: it is located in the proto-oncogen and inhibits the migration of melanoblasts. As a result, the latter do not have the opportunity to get into the skin in time, which means that the pigment does not reach the hair coat. Therefore, a white coat is formed.

If some melanoblasts penetrate into the hair sacs on the cat's head, this causes the appearance of colored spots. Mutational melanoblasts can reach the retina, but their number can be different: with a small number, the color turns blue, and if there are many, the pupils will be yellow.

On the same chromosome - a particle of heredity is responsible for the gene for painting hair coloring. Its usual structural form gives a banded color, and the stripes can be interrupted or be continuous. There is a semi-dominant change, for example, the Abyssinian tabby. Homozygous individuals with a pair of ordinary structural forms for this change are generally without stripes and their coat color is uniform. But in heterozygous individuals from such a mutation, bands appear on the muzzle, legs and tail. When the change is recessive, the transverse stripes are deformed in the line of irregular shape and a powerful black longitudinal stripe appears on the back of the cats.

Mutations in the gene that affects the tyrosinase enzyme cause albinism, which occurs not only in cats, but also in other mammalian species. Decreased tyrosinase activity depends on the temperature of the cat - the lower it is, the more active the enzyme. From this comes a more intense staining of the peripheral parts of the body: nose, tips of paws and tail, ears of Burmese cats.

  • Subclass: Theria Parker et Haswell, 1879 = Viviparous mammals, real animals
  • Infraclass: Eutheria, Placentalia Gill, 1872 = Placental, higher animals
  • Squad:Rodentia Bowdich, 1821 = Rodents
  • Family: Cricet> Sizes from small to medium. Body length 8–25 cm. Tail length 2.5–10.6 cm. Body type typical for hamsters, heavy, muzzle blunt, limbs short (fig.). The ears are relatively small, slightly protruding from the fur, densely covered with thin silky hair. Eyes of medium size, relatively smaller than those of Dzungarian hamsters. The soles of the feet are bare, sometimes covered with hair. The tail is weakly pubescent with hair or almost naked. Cheek pouches are well developed. The hairline is thick, rather long and soft. Its coloration on the dorsal side of the body is usually gray, sometimes reddish or dark yellow, on the ventral side light gray or white. The limbs and tip of the tail are white. In the Daurian hamster, a dark brown stripe runs along the middle of the back. Nipples 4 pairs.

    In the skull, the facial section is somewhat elongated. The brain capsule is not narrowed. Interorbital narrowing is well defined. Zygomatic arches not wide apart, especially in front. Frontoparietal crests are usually not. The inter-parietal bone is wide. Incisal openings wide, often reaching the level of buccal teeth. The bony palate extends a little further back to the level of the last buccal teeth. Bone auditory drums of relatively large or medium sizes, not flattened, their front section is not elongated into the tube.

    Distribution covers a large territory from southern and eastern Europe, through Asia Minor and Western Asia to the MPR and China, Soviet Primorye and the Korean Peninsula, inclusive.

    Chromosomes in a diploid set from 20 in the Barabinsky, 24 in the long-tailed and up to 28-ZO in the rat-shaped hamster.

    There are 10 species in the genus:

    gray hamster - C. migratorius Pallas, 1773 (from the Eastern Balkans in the west to Altai, western Mongolia, Northeast and Central China in the east and from the northern reaches of the forest-steppe in the CIS in the north of the range to Iran and Afghanistan, Asia Minor, Syria, Palestine, Balochistan and Kashmir in the south, in the CIS, the northern border of the range passes approximately along the lines of Chernivtsi, Shepetovka, Zhytomyr, Kiev, Chernigov, Kaluga, Ryazan, Gorky, Kazan, Ufa, the southern tip of the Urals, northern Aral Sea, and the southern shore of Lake Chelkar- Tengiz, north of Bet-Pak-Dala and the Kazakh Highlands, Semipa Latin, southwest of the Altai Territory),

    Eversmann hamster - S. eversmanni Brandt, 1859 (Russia - Trans-Volga region, southeastern regions of Tatarstan, Southern Urals, Volga-Ural interfluve, Northern Kazakhstan, Mongolia, Northern China),

    long-tailed hamster-C. longicaudatus Milne-Edwards, 1867 (in Russia - Tuva, the extreme south of the Krasnoyarsk Territory, the Jida River in Transbaikalia, Mongolia, China),

    barabinsky hamster -C. barabensis pallas, 1773 (Russia - Baraba forest-steppe, pre-Altai steppes, Tuva basin, Baikal region to the north to the upper reaches of the Lena, Transbaikalia steppe to the north to the Sretensk-Chita-Ulan-Ude line, the Far East - the middle reaches of the Amur and the south of Primorye, Mongolia, Northern China) ,

    Chinese hamster-s. griseus Milne-Edwards, 1867 (North China),

    Transbaikal hamster - S. pseudogriseus Orlov et Iskhakova, 1974 (Southern Transbaikalia, eastern part of Mongolia),

    Tibetan hamster - S. lama Bonhote, 1917 (Tibet),

    Short-tailed hamster-C. aliicola Thomas, 1917 (Tibet, Kashmir),

    Mongolian hamster -C. curtatus G. allen, 1925 (Mongolia),

    rat hamster - C. triton de Winton, 1899 (in Russia - the southwestern part of the Primorsky Territory, the Korean Peninsula, Northeast and Central China).

    The structure of the chromosome in late prophase metaphase mitosis. 1 chromatid, 2 centromeres, 3 short shoulders, 4 long shoulders ... Wikipedia

    I Medicine Medicine is a system of scientific knowledge and practice, the goals of which are to strengthen and maintain health, extend people's lives, and prevent and treat human diseases. To accomplish these tasks, M. studies the structure and ... ... Medical Encyclopedia

    A branch of botany that deals with the natural classification of plants. Instances with many similar characteristics are grouped into groups called species. Tiger lilies are one species, white lilies are another, etc. Similar species in turn ... ... Collier Encyclopedia

    ex vivo genetic therapy - * ex vivo genetic therapy * ex vivo gene therapy gene therapy based on isolation of the patient’s target cells, their genetic modification under cultivation and autologous transplantation. Genetic therapy using germline ... ... Genetics. encyclopedic Dictionary

    Animals, plants and microorganisms are the most common objects of genetic research. 1 Acetabularia acetabularia. The genus of unicellular green algae of the siphon class is characterized by a giant (up to 2 mm in diameter) core namely ... ... Molecular biology and genetics. Explanatory dictionary.

    Polymer - (Polymer) Definition of a polymer, types of polymerization, synthetic polymers Information about the definition of a polymer, types of polymerization, synthetic polymers Content Description Definition Historical background The science of Polymerization Types ... ... Encyclopedia of the investor

    A special qualitative state of the world, perhaps a necessary step in the development of the Universe. A naturally scientific approach to the essence of J. is focused on the problem of its origin, its material carriers, on the difference between the living and nonliving, on evolution ... ... Philosophical Encyclopedia

    1. A total of 7 genera of hamsters are known, including about 19 species. The largest is an ordinary hamster (up to 35 cm in length, weight up to 400 g or more), the smallest is a Roborovsky hamster (4-5 cm in length, weight usually does not exceed 10 g). Dagestan hamster 2. In the wild, hamsters can be found in the steppes, semi-deserts and deserts of Eurasia. Some hamsters climb mountains up to 4000 m, some enjoy living next to a person - in the fields, in gardens, kitchen gardens and even in buildings.

    3. A pet that is popular in many countries - a golden or Syrian hamster in nature has a rather limited range - it can be found in western Syria and the border regions of Turkey. Millions of animals of this species, living in homes and laboratories around the world, all come from the one and only brood obtained by Professor Aharoni in 1930. Khomyachkov was able to propagate, and a year later part of the resulting offspring was exported to England, from where they began their further “procession around the world” as domestic and laboratory animals.
    Baraba hamster 4. Several other species are also kept in captivity: the Chinese hamster, and representatives of the genus of the bipedal hamster — the Dzungarian, the Campbell hamster and the Roborovsky hamster. The rest are practically unknown to anyone except zoological specialists.

    5. The idea of ​​hamsters as good-natured bumps is not quite true. Most of them are rather aggressive animals. In nature, almost all hamsters lead a solitary lifestyle, not maintaining any constant positive contacts with their fellow tribesmen. By smell, the male finds a female ready for mating, mates with her, and this is where his participation in procreation usually ends - the female grows cubs alone. This asociality of hamsters extends to communication with humans: in captivity, as a rule, they are poorly tamed, do not become attached to the owner and are not interested in communicating with him. In lines that have been brought up in captivity for many generations, aggression towards humans is usually stopped, but you should not expect the same from animals caught in nature: when you try to pick them up they will violently bite, and representatives of relatively large species bites can be very painful.
    Gray Hamster 6. Contrary to popular belief, hamster holes are almost never complex. In general, the life of a loner and does not have to acquire a large and complex housing. The hamster’s burrow, as a rule, has one or two exits, a nesting chamber and, in some cases, a pantry. But the volume of stocks in some species can be very significant. Hamsters do not fall into real long hibernation (such as gophers), so they have to take care of the "food warehouse" for the winter - so as not to be so sad to spend long winter evenings.
    An ordinary hamster 7. One of the most probably known features of hamsters is their cheek pouches.This device really deserves at least a separate mention. It is clear that in order to create any significant feed reserves, you need to have a device for their transportation. In this case, evolution “tried” - in the cheek pouches, hamsters can carry a feed volume comparable to the size of the hamster itself.

    8. As everyone knows, the basis of the diet of hamsters is grain (seeds of various plants, both wild and cultivated). However, in addition to this, hamsters can use a variety of power sources. The green parts of plants are used mainly as a source of water - since plentiful dew does not always fall out, and hamsters most often have no other ways to get water in nature. Hamsters of some species can happily use various fruits and root crops for food. Also, most species exhibit predatory tendencies to one degree or another and make up for the lack of protein due to animal food - from insects to frogs and lizards.
    Gray hamster 9. The uniformity of the “hamster” look and lifestyle has its exceptions. For example, the name of the rat-shaped hamster speaks for itself - in appearance it can really be confused with a rat. The “rat” color, the elongated body shape, the relatively long tail - all this goes well with the “rat” lifestyle: unlike other types of hamsters, the rat-shaped hamster inhabits relatively moist habitats and has an appropriate metabolism.

    10. In total, 7 genera of hamsters are known, including about 19 species. Around - because the status of some forms remains the subject of discussion by zoologists. Hamsters Dzhungarsky and Campbell were previously considered one species, but now the species status of each of them causes no doubt. But hamsters of Barabinsky, Transbaikal and Chinese are considered by some researchers to be different species, while others are considered forms within the same polymorphic species. They differ in the number of chromosomes, but give fertile offspring.

    George Rurikov,
    Institute of Problems
    Ecology and Evolution (IPEE RAS)

    Pin
    Send
    Share
    Send