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Jerboas belong to the family of mammals of the order of rodents, whose representatives live in the steppes, semi-deserts and deserts of the Palaearctic. Thus, these rodents are adapted to the specific living conditions in these territories.
Jerboas are rodents that range in body length from four to twenty-six centimeters (that is, jerboas range in size from very small to medium). Jerboas have a long tail (from seven to thirty centimeters). The latter is often endowed with a flat brush that has a black and white color. The brush acts as a steering wheel when the animal is running.
The head is quite large, and the neck is almost invisible from the outside. The muzzle is a little dull. The ears are usually rounded and long, covered with sparse hair.
Jerboas have big eyes. The hair of the jerboa is very soft and thick. The upper body is usually buffy-sandy or brownish in color.
The number of teeth in these animals varies from sixteen to eighteen. The incisors have several functions. First, they are, of course, necessary for chewing food. And secondly, they play a leading role in loosening the soil during digging. Already loosened soil, the animals rake with the help of their limbs.
For jerboas, such a phenomenon is characteristic as hibernation, in which animals usually lie in September, and wake up in early spring.
Pregnancy of female large jerboas lasts about twenty-five days, after which an average of three to six cubs are born. Jerboas reach sexual maturity by the age of two.
Jerboas have strong hind limbs. It so happens that the length of the latter is four times the length of the forelimbs. Only some jerboas move with all four limbs, and then only if the movement is slow. Most species of jerboas move exclusively on their hind legs. If the movement is fast, then the jerboas cover the distance with the help of jumps, the length of which reaches three meters. This method of movement is possible thanks to the modified hind limbs of the animal. Such changes include: fusion of the three middle metatarsal bones into one bone (called the tarsus), shortened lateral toes (or none at all), lengthening of the foot itself. In representatives of those species of jerboas that live on sands, an increase in foot area is sometimes achieved due to coarse hair. The latter in this case create a kind of "brush" around the foot. The forelimbs of representatives of jerboas are short. Claws are well developed. Moreover, the latter, as a rule, are somewhat longer on the hind legs than on the front ones.
When moving, the tail is of great importance. Or rather, its peculiarity is to be long. The tail plays an important role in jumping, serving as a balancer. The tail of the jerboa is very necessary in this role during sharp turns at considerable speed.
The large jerboa is the largest member of the family. The body length of an adult reaches twenty-six centimeters. The length of the tail (which ends with a fluffy tassel) is approximately thirty centimeters, which is 1.3 times longer than the body of the animal. The weight of a large jerboa is approximately three hundred grams. The muzzle of a large jerboa is wide and slightly elongated. The hind legs have three-toed feet. The jerboas move by jumping, which is carried out exclusively with the help of the hind limbs. The animals can reach speeds of up to fifty kilometers per hour.
The tail carries information about the jerboa. You can say so. By the tail of this animal, it is possible to determine whether the jerboa feeds well enough. The emaciated jerboa has a tail with protruding vertebrae. A well-fed jerboa has an almost round tail.
For jerboas, such a concept as geographic demorphism is applicable. This is manifested, in particular, in the following: the color of the back of the jerboa changes (brightens) when moving from west to east and from north to south, in addition, when moving from north to south, the ears of jerboas become longer.
The distribution area of the large jerboa is limited to areas with a dry and arid climate. In practice, this is so, although this animal can adapt to other living conditions. Thus, the large jerboa is distributed in the territory from the forest-steppe to the northern part of the desert zone (including semi-desert) in the south of Western Siberia, as well as in Eastern Europe and Kazakhstan. The distribution area of the large jerboa is represented not only by a continuous massif (the main habitat is the territory from the Altai Mountains and the Ob River to the Black Sea coast), but also by single isolates (for example, such an isolate with an area of about 82,400 square kilometers is available in the northern foothills of the Tien Shan ). The northern border of the main distribution area for the most part coincides with the northern border of the forest-steppe, and the southern border runs along the northern Black Sea coast, along the foothills of the Caucasus, after which it skirts the Caspian Sea from the northern side and continues to the east.
The large jerboa is widespread. Within its habitat, this is indeed the case. However, its distribution is very uneven, the reason for which lies in the variability of the natural habitats of the large jerboa, as well as with an increase in the influence of the human factor. As for the latter, the following example is very pertinent. Until the mid-1990s, representatives of the large jerboa met in their natural habitats in the area of the city of Serpukhov. However, due to the destruction of their habitat, these animals died out in the vicinity of this city. The density and number of local populations of this animal increases as it moves from north to south.
The large jerboa is not very important to humans. The fishery for the preparation of skins of this animal was carried out in Kazakhstan in the period from 1920 to 1960, but at present it has been discontinued. The reason for this was the fact that the great jerboa is a natural carrier of tularemia, plague, and Q fever pathogens. For some people, the jerboa has a certain meaning as a pet.
Large jerboas are characterized by the presence of a considerable number of habitats. The sparse grass stand in open areas becomes a place for the population of large jerboas in the northern part of their habitat. Field edges, dirt road sides, gentle ravine slopes, etc. become the location of jerboas in the steppe zone of their habitat. These animals inhabit the entire desert zone, with the exception of areas with moving sands, and are also often found in mountainous areas at an altitude of 1650 meters above sea level.
By way of life, jerboas are loners. They make contact with each other only during the breeding season. Moreover, jerboas are active only at night. These animals emerge from their shelters to the surface about half an hour after sunset. The jerboas return to their burrows about thirty to fifty minutes before sunrise. During the night time, these animals cover a distance of about four kilometers. The day is used by jerboas as an opportunity to sleep well before the next nightfall.
Jerboas are extremely wary animals. Due to this feature, the animal will never leave its hole if it feels the slightest potential danger.
The large jerboa is a good digger. Individuals living on gravelly and clayey deserts, when building up their underground shelters, encounter dense soil. The thin and long front incisors allow the jerboas to cope with this task. Individuals living in sandy deserts use their front limbs to build shelters. Immediately, the incisors are used only when, when digging a hole, strongly compressed sand or a plant root suddenly comes across.
Jerboas equip themselves with both permanent and temporary burrows. Permanent burrows are subdivided into wintering and summer burrows and have a rather complex structure. Temporary burrows are much simpler than permanent shelters. An almost horizontal passage leads to the permanent burrow, the length of which often reaches six meters; in the middle of the stroke, the inclined stroke is separated sharply down. In addition, from the main course, there are sometimes branches (the number of which varies from one to four). Their function is to create one or more emergency exits for the jerboa. The inclined path leads to the nesting chamber of the animal (where there is a spherical nest made of moss, wool, down, feathers, dry grass), which is localized at a depth of forty to one hundred and ten centimeters. The horizontal course used by these animals during the day is clogged with an earthen plug. The popular name for this plug is the navel. Winter burrows are much deeper than summer ones. They can be localized at a depth of two and a half meters. The winter burrows include two nesting chambers located at different depths. The temporary burrows of the jerboa are shallow. They are made in the form of a move that goes obliquely into the ground. One animal can have several shelters connected to each other by galleries. Some jerboas living on the northern border of their distribution range use empty gopher burrows.
The large jerboa is an omnivorous rodent. The animal eats not only plant products, but also animal products. The former include the roots, bulbs and seeds of plants. The second group includes insects. The jerboa easily changes one food for another. However, this process is directly related to the availability of a particular food, and in addition, it also depends on the season. Still, the diet of jerboas includes mainly green parts of plants, bulbs and seeds, that is, food of plant origin. Jerboas often diversify their diet, picking up sown seeds of melons and watermelons, as well as peas, sunflower seeds and cereals.
For jerboas, such a phenomenon as hibernation is characteristic. As for some other representatives of rodents. The beginning of hibernation in jerboas falls on the autumn onset of cold weather, as a rule, this occurs in September. True, there are times when jerboas go into hibernation only in October. The duration of hibernation in jerboas, as a rule, varies from four to six and a half months, but may be interrupted during thaws. The duration depends on the region of residence of the jerboa. A large jerboa does not accumulate food for the winter time, compared, for example, with chipmunks. Instead, the large jerboa becomes very fat before hibernation. At the same time, his body weight often almost doubles. Hibernation ends in the first half of spring, after which the mating season begins immediately. Pregnancy in females of large jerboas lasts about twenty-five days - each year a female jerboa brings one litter (two very rarely). The number of cubs varies from one to eight, usually three to six - until the age of one and a half months, the cubs live with their mother. Large jerboas reach sexual maturity at about two years of age. Their average life span is three years, which is associated not only with the presence of a large number of enemies, but also with physiology (although the former is very important).
Jerboas have a large number of enemies. This circumstance strongly affects the average life span of these animals. The enemies include mammals and birds of prey, reptiles. In addition, considerable harm to the populations of these animals is caused by the influence of an anthropogenic factor, namely, the urbanization of the natural foci of the jerboa habitat.
Jerboas can be kept at home. But of course, this animal is not the best choice when choosing a pet. The reason lies in the natural features of the jerboa: jumping and fast running are vital for it, because these animals are very active, and the living conditions, of course, do not allow animals to fulfill their natural needs. The jerboa is a fairly clean animal. They take great care of their fur coat. In addition, they choose a strictly defined place for the toilet. In view of this quality of animals, cleaning in a new habitat for them should be carried out as needed.
Jerboas are difficult to domesticate. These animals get used to humans very hard. Moreover, contact with humans during the daytime causes stress in jerboas. This inevitably leads to a violation of the vital rhythm of animals that are active during the daytime and at night. But even if the jerboa gets used to a person and goes to his hands, this animal remains just wild for its entire life.
The conditions of keeping the jerboa should allow the animal to receive sufficient physical activity. If a person nevertheless decided to light the jerboa, then he should think about the implementation of this condition. Otherwise, the jerboa can fall ill with hypodynamia and even die. Jerboas must be kept in spacious cages or aviaries, which are of considerable size. This applies not only to the length and width of the limited space, but also to the height - the fact that these animals are capable of jumping up to half a meter in height must be taken into account. Another mandatory condition of detention is the absence of any items made of plastic in the cells. In no case is it allowed to use a plastic pallet, which the animal chews through without much difficulty, and as a result of which it can easily escape. It is impossible to keep several jerboas in one cage or in one aviary at once. This is due to the fact that the animals are quite aggressive towards their relatives.
The landscape in the enclosure must be similar to the natural one. That is, it is necessary to create such conditions that will be as close as possible to the habitat of jerboas in their natural environment. At the bottom of the cage or aviary, it is required either to cover it with sod, or to cover it with sand. This is due to the fact that jerboas in their natural habitat conditions live on soft soils. Hard bedding in the cage can cause serious injuries to the paws of these animals. In addition, the new habitat should have a drinking bowl, bowls for food. The drinker can be presented both as a dispenser and as an ordinary bowl of water. The cage should contain various roots, small sticks, dry grass. These are materials from which the jerboa can equip a nesting house for itself. The animal needs it in order to hide from danger and stay in a state of sleep. Sod litter has its advantages. They boil down to the fact that the jerboa will be able to dig holes, even if they are small. This is an instinctive trait bestowed on animals by nature. Its absence can cause a breakdown of the animal's nervous system and its being in constant stress.
Jerboas can be released from their cage. In no case! At the first opportunity, these animals will escape from the cage. After that, they will hide in the most secluded place.Their extraordinary abilities will help the animals make a new hole for themselves. During the night hours, jerboas are able to gnaw a course 20-30 centimeters long when it comes to a concrete wall of a house, and 50 centimeters when it comes to a brick wall of a house - thus, they go to sleep in a new hole. The latter, by the way, as in nature, clogs up. Only in this case, the jerboas close the entrance with a crumb of concrete or brick.
The diet of jerboas when keeping these animals in an apartment should be similar to their diet in natural habitat. Jerboas do not need to give anything salty, peppery or sweet. Food prepared for humans is not suitable for a jerboa. Exotic fruits and berries, as well as seafood are also recommended to be excluded from the jerboa's diet. The main food for this animal should be cereal mixtures, fruits and vegetables; jerboas are fed a wide variety of cereals. Their diet should preferably include melon, watermelon, pumpkin, sunflower seeds, beets, carrots, apples, pears, potatoes, dandelion leaves, in addition, jerboas are always not against eating plant roots. In winter, it is recommended to give these animals thin sticks of willow, aspen, maple. Do not forget that jerboas are omnivorous by nature, so it is undesirable to limit yourself only to plant foods - crickets, grasshoppers, mealworms and moths, along with plant foods, will make the jerboa's diet complete. Jerboas don't drink much water. However, it must always be available to the animals. It is important to keep the water and all other food items clean and change every day.