You are mistaken if you think that man dominates the earth. For a long time already all continents, cities, villages and almost every corner of nature subjugated the beast, whose name is the rat pasyuk, or just gray. Most of us cannot stand them. And they’re doing it right, because rats eat a huge part of the crop, maim pets and birds, and reward us with deadly ailments. But on the other hand, in laboratories they give their lives in thousands, helping us deal with diseases, including cancer and AIDS, test the effects of toxins and new drugs, and “work” on the secrets of genetics and psychology. Do you know how the rat pasyuk lives? How is he looking for a mate? How does offspring grow? Why settles next to a man? We will tell you about rats all the most interesting.
Where did they come from
12 thousand years ago, gray rats lived only in East Asia. The ice age left them a small space, where East China is now located.
With the warming rat, the pasuk gradually occupied Altai, Primorye, Transbaikalia, and the south of China. But large-scale migrations have occurred with the development of navigation. It was on the ships that the tailed animals moved to Europe, Australia, Africa, America, having populated all settlements and suitable natural spaces. Now they are not only in Antarctica and in the Arctic. As they arrived at new places on ships, even a certain John Birkenhout, an English naturalist, christened them Norwegian rats, thinking that schooners and bots came to England from there, and not knowing that at that time there were no rats in Norway. Despite the mistake, the name of the species Rattus norvegicus exists to this day.
Rat pasyuk: description
Among their relatives, these rodents are considered large. Males grow to a length of 25 cm, plus a 19 cm bald tail. In this case, the weight of an adult is up to 400 grams. The sizes of the females are a bit more modest. There are no other external differences. Pasyuk's muzzle is often not very elongated, ears are small. The fur of rats is conditionally gray, but red, dark, brownish shades, similar to agouti, may also be present, which is why they are called brown abroad. Rarely, there are pasukas pure black and pure white. The abdomen of everyone is also white, and throughout the body there are long ostral hairs, often dark at the base. There are two subspecies of Pasyuk - Indian and East Asian. In rats, the chromosome set is 42 units, and they have 25,000 genes, so all sorts of combinations are possible.
Behavior
The gray rat pasyuk is a social beast; in nature it lives in groups; loneliness is extremely rare. One family can occupy an area of up to 2 square km, which is carefully marked and guarded. But if necessary, called "food extraction", the boundaries of the territory are easily expanded. A family can have from 100 to 2000 members. Among male rats, like other mammals, there is a strict hierarchy consisting in the selection of females for the extension of the genus. But there is no help and protection for each other. Rats are always self-explanatory. They are very smart, have a good memory, if everything suits them, they are not aggressive, but they can stand up for themselves. Rats fight excellently, and not only with relatives, but also with large animals. Previously, the English sirs even staged spectacular rat-dog fights, which, fortunately, had already been banned.
Nutrition
Rat pasyuk - omnivorous beast. In nature, its menu includes grains, vegetables, fruits and necessarily proteins: eggs, chicks, fish, seafood (stolen or thrown to the ground), insects, small rodents, sometimes even feces. Having settled near a man, the rats somewhat changed their gourmet tastes. Now in their menu there are any food leftovers, products left unattended (especially grain in granaries), as well as electrical wiring, books, and other things people need. An interesting fact: in order to get a tidbit, a rat is able to squeeze into a hole where its relatively small head was able to crawl. Pasyuki have chosen warehouses, cellars, subways, and in their homes they travel freely along the sewer network and garbage chutes.
Breeding
Just fantastically prolific rat pasyuk! The photo above captures a 3-day brood. These caudate become sexually mature as early as 3 months old! Females in females can have up to 20 pieces per litter. Often 3-4 mothers arrange a common nest to take care of the babies. Scientists have noticed that in such cubes, the bodies of newborns are sometimes intertwined, and it seems that the grown up rats are two-three-headed. Perhaps this was the prototype of the rat king from The Nutcracker.
In nature, animals build nests in hollows or dig shallow burrows. In cities, they settle in any suitable place. After 18 hours, the female who resolved from the burden can conceive again, and her pregnancy lasts only 24 days. Imagine the progression of the rat population!
Newborn baby rats are real babies weighing up to 5 grams. They can be enjoyed by a hungry dad, and sometimes by a mother, if she thinks the children are too weak. But mostly females are rather caring, lick their tailed children, feed them very nutritious milk, clean up the nest.
Until 17 days, children remain blind, but at the age of 1 month, and sometimes only 21 days old, they begin an independent life. Now there are about 15-18 billion rats on Earth, almost twice as many as we humans. And this despite the fact that the growth of their population is restrained by diseases, predators, people and too short a life span not exceeding three years, even in the most ideal conditions.
Highscores
The rat pasyuk can surprise with its abilities. In case of danger, it jumps up to 80 cm in height, up to 1 meter in length, accelerates up to 10 km / h, can swim in water for 3 days, and winds up to 17 km per day by land. These animals can be said to be extreme. They can live and even breed at -18 ° C. So, in one of the meat freezers, rat nests with babies in frozen carcasses were discovered. They calmly tolerate heat up to + 45 ° C, and even radiation up to 300 x-rays per hour. Where atomic explosions were carried out and all living creatures were destroyed, only the pasuk rat remained unharmed. Their small ears are capable of catching the tiniest noise in the 40kHz range. We only capture up to 20 kHz, which is perfectly used in ultrasonic repellers.
But with eyesight in rats is rather weak. They have a viewing angle of only 16 °, so they often have to turn their heads. Of the flowers, they distinguish only bluish-green, and basically they see everything in gray colors.
Each individual needs only 20 grams of food per day, but this is already 10 kg per year. Without food, rats can last only 4 days. It was the search for food that caused them to move to new territories. Pasukas also need water. If their menu consists of only dry feed, they can live only 5 days without drinking. If the feed contains at least 50% moisture, it lasts for almost a month without water.
Harm and Benefit
Rodents living only in nature annoy people a little. All they can do is gnaw vegetables in the garden or grain in the fields. A much more unpleasant pasyuk house rat. There are two varieties here - those who live with a person constantly, and those who move to people only in the cold. Both of them are capable of completely destroying supplies of food, de-energizing the house and entire areas, biting off wiring, eating paws of poultry and rabbits, killing rabbits, chickens and other chicks. But the worst thing is that rats suffer from plague, typhus, Q fever, salmonellosis, helminths and other infections. For all these reasons, people are constantly fighting with pasukas, poisoning them with poisons, and setting traps.
But on the other hand, it is rats, due to their fantastic fecundity, that are the main experimental animals that are tested on drugs, conduct a bunch of experiments, infecting them with all kinds of diseases, in order to find treatment for them later. Therefore, despite the damage caused by the pasukami, you need to have a share of respect for them.
Pets
It turns out that there are people who enjoy rats with great pleasure and even save them from trouble. One such community of rat lovers is called Felis Lynx (rats). "What happened to the pasuk?" - This is one of the topics on their forums on the Internet. A community has been created so that everyone who wants to have a rat in their home can help with advice, because raising a little easter is not so easy. There are people in the community raising exclusively domesticated animals that are more sociable, not at all aggressive, a kind of small living lumps that require love and care. But there are people who undertake to go out wild rat pups. Pasyuki also get used to captivity, with difficulty, but are tamed, respond to a name, and can even afford to play with them. But for example, males are more difficult to tolerate the appearance of an alien in their cage, they can even bite him, at first they can hardly clean the cage or bowl of food.
Selection
The large fecundity of rats helps to breed their numerous breeds. Basically, they differ in the color of the eyes and hair. There are even sphinx rats (bald), downy rats (with a delicate fluff instead of wool) and double-rex (these have changed parts of their body covered with wool all their lives). A hybrid of a pasuk and a decorative rat, which has lost some of its former talents, can also be obtained. This is done in the project "Home Pasuk." Children from such a union are born not only of a variety of colors, but also stronger, more savvy. True, sometimes this offspring comes out somewhat aggressive. In general, messing with rats is very interesting. They are affectionate animals, neat, eat little, are trained and take up very little space in the apartment.