In winter, mammals hibernate because. Hibernation

This is a playful version of the answer to the question of why animals hibernate in the winter. But of course she is wrong. There is another version of the answer to this question, which is also incorrect. Many children (and adults too) believe that animals sleep in winter to wait out the cold. This is only partly true. Of course have cold-blooded animals These are animals that cannot maintain their body temperature on their own. In order to lead an active lifestyle, they need heat to come from outside. Such animals include reptiles, amphibians, fish and all invertebrates: insects, mollusks, worms, etc. As soon as the air temperature drops to a certain point, they all hibernate.
But they are not the only ones sleeping. Some sleep in winter warm-blooded animals : many rodents, hedgehogs, badgers, raccoons. And, of course, the most famous of the dormouse is the bear.

Exercise.
In this picture, I drew different animals. Ask your child to name which ones are warm-blooded and which ones are cold-blooded.

If everything depended only on the cold, then why doesn’t he sleep in the winter polar bear, although it lives in a much colder climate than brown? We have already studied why polar bears do not freeze in winter: they have a number of adaptations to keep warm. But after all, the brown bear also has its own adaptations in order not to freeze. Moreover, he is not much warmer to sleep than not to sleep. After all, bears sleep in winter not only in closed dens dug in the ground (which are called unpaved), but they also use riding dens, i.e. simply pits in which they sleep right under the snow. And they must be cold there.

So, something else besides the cold, in winter, makes animals hibernate. And what else distinguishes winter from other seasons, except for the low air temperature? The lack of vegetation. There is no grass, no berries, no flowers, no green leaves. Therefore, herbivores that fed mainly on them experience great nutritional difficulties.
Ask the child what kind of wild animals does he know (domestic animals are not considered here, because people take care of their food), which feed on vegetation? These are deer, moose, roe deer, wild boars and other ungulates. These are many types of birds and fish. These are rodents. And if large herbivores can somehow get their own food: digging it out from under the snow, switching to eating branches and bark of plants, moss, etc., then small animals cannot live without plants. That is why they go into hibernation. In winter, many rodents sleep: ground squirrels, hamsters, marmots, dormouse.
And since in winter there is not only vegetation, but also small rodents, frogs, worms, mollusks and other small living creatures, as well as insects, then there is nothing to eat for animals that fed on them: many birds, hedgehogs, shrews, bats, badgers, raccoons - striped and bears. And they have to either move to warmer climes where insects do not sleep (as birds do), or hibernate (as hedgehogs do). And some do it at the same time: for example, insectivorous bats are leather. They are typical inhabitants of urban buildings and are distributed over a vast territory, including all continents except Antarctica. With the onset of winter, the leathers migrate from the northern territories, flying like birds, to the south. And there they hibernate in caves, attics and other secluded places.

I drew pictures with various animals and their food. These cards can be printed by downloading the full size file from Yandex.Disk

They can complete several tasks.
1. Invite the child to take a card with a favorite animal and choose from the rest of the cards those that show what he eats. For example, a fox eats eggs, mice, hares, snails, lizards, beetles.
2. Invite the child to find and make different food chains - who eats whom. For example, "grain-mouse-hedgehog".

By the way, animals hibernate not only from the cold, but also from the heat. Except winter also happens aestivation . Those animals that cannot maintain the body temperature they need in conditions of high temperature and drought fall into it. These are some fish and amphibians, as well as mammals. For example, the African hedgehog and tenrec (Madagascar insectivorous animal). The sandy ground squirrel, which lives in Central Asia, Kazakhstan and the Volga region. The most amazing thing is that his summer hibernation without interruption turns into winter! And he wakes up only in February-April. That is, this gopher does not sleep only 2-4 months a year!

Thus, we can conclude that hibernation is needed by animals as a seasonal adaptation to adverse conditions. environment. Some animals switch to other food, while others hibernate.

Sleep is different.
Very few animals sleep in a deep sleep that cannot be interrupted by anything: these are bats, hedgehogs, ground squirrels, hamsters, jerboas, dormouse, marmots. Are you familiar with the expression "Sleep like a groundhog"? So they say precisely because it is almost impossible to bring a groundhog out of hibernation. In such a deep hibernation, the animal's metabolism decreases, the temperature drops to near zero (from +5 to -2 in ground squirrels, according to some reports), the heart begins to beat almost 10 times less than usual, the respiratory rate decreases 40 times. All this is necessary in order for the animal to spend as little energy as possible. It is like a computer or a phone that "goes" into standby mode, lives in economy mode. This state is actually called true hibernation.

Hazel dormouse. Photo from Wikipedia

Another type of hibernation superficial (superficial numbness) . Such hibernation is typical, for example, for bears, chipmunks, and prairie dogs. During sleep, the animal's body temperature decreases, but slightly: by several degrees. And the heartbeat and breathing roughly correspond to normal sleep. Such an animal is easy to wake up.

And there is hibernation daily - Hummingbirds and bats fall into it. They cannot maintain their body temperature on their own, so at night, during a period of cooling, they fall into a stupor that lasts until morning.

Bat. Photo from Wikipedia

Exercise:
Look at the picture with winter forest and look for all the animals on it. Which one is hibernating? (In order for the picture to open in full size, it must be opened in a new window by “clicking” on it with the right mouse button).
If desired, this picture can be printed and given to the child to color.

At the end of my story, I want to offer you make a craft.
Choose a hibernating animal with your child. Maybe it will be a bear, a chipmunk, a hedgehog or a snake, or maybe a sandy gopher or an animal with a speaking name dormouse? Find out in the encyclopedia or the Internet how he arranges a place for hibernation. And try to make this "bedroom" with your own hands. If you wish, post the craft on your blog and leave a link to it in the comments here. It will be interesting to visit you and see what you can do 🙂
Katya, for example, chose a hamster. We learned that hamsters build very complex burrows, with burrows, numerous pantries and different chambers. They line their winter nest with soft straw. We didn’t have straw, so Katya simply cut strips of yellowish paper. Here is the nest for the hibernation of the hamster she got:

And I also want to give a little a list of cartoons that tell about how winter hibernation goes for fairy-tale animals.

Distinctive features

The brown bear is a large animal. Individuals living in the European part of the continent reach 1.4 - 2 m with a weight of up to 400 kg. Bears of Kamchatka and Alaska can weigh up to 1000 kg. Such a giant, standing on its hind legs, has a height of up to 3 m.

Body brown bear powerful. The head is massive, with small eyes and ears, high withers, thick fur, wide set and short tail - the typical appearance of brown (up to 10 cm long) does not hide on powerful five-fingered paws.

Bears are plantigrade animals. If necessary, for a short time they develop speeds up to 40-50 km / h. Water obstacles are overcome with ease. It will not work to hide on a tree from an angry bear.

Their diet is dominated by plant foods (by ¾). First of all, these are berries, acorns, nuts, roots and tubers of plants, as well as their succulent stems. It is this feature that is decisive in understanding why the bear hibernates in a harsh time. As for the color, the main color is brown. The shade of wool can differ significantly even in individuals living in the same territory (from black, fawn-gray and gray to reddish-brown).

Lifestyle

Bears define their territory and fix the boundaries with marks. It is believed that they live settled, although they may make migrations associated with the search for more suitable feeding places. In early spring, they look for clearings where the snow melts and the ground thaws faster. During the period of midge activity, they can leave the thicket to open places. During spawning, they make trips to rivers to hunt for fish in shallow water.

But they cannot move to the southern regions during the winter - this is another good reason in understanding why bears hibernate in winter. They lead and are forced to return to their traditional habitats. With the advent of autumn, food is becoming more difficult to find - you have to look for a way to wait out the cold.

The ability to fall asleep in the cold is also characteristic of other animals. By the way, not only the winter period causes hibernation. In the desert area, small rodents can enter a sleepy state in the summer, during a period of drought. Under adverse conditions, unplanned hibernation can last until spring.

A brown bear cannot afford such a long rest. The period of his hibernation can vary from 2.5 to 6 months. But sometimes it lasts longer if circumstances so require. It is difficult to answer the question why the brown bear hibernates, and does not prepare stocks of roots, nuts and acorns for the winter. Apparently, he prefers to store them in the form of subcutaneous fat - it is more reliable and warmer.

It should be clearly understood why the bear hibernates. This is caused by the only way animals can survive the winter. At the same time, it should be noted that individuals living in the southern regions with a sufficient food supply can do without seasonal sleep all year round.

It is also worth dispelling the myth about the alleged ability of bears to suck their paw and thus eat in winter. This habit, according to experts, is associated with the peculiarity of the molting of the soles of bears. climbs off them during their stay in the den. This is due to lack of movement and load. Young and delicate skin on the soles freezes. Therefore, the bears warm it with their breath and lick it with a warm tongue.

Rods: why the bear hibernates in winter

What happens if you wake up an animal in a lair? Hibernation of bears is superficial. An alarmed animal will wake up and be able to quickly react to danger or abrupt change conditions. As a rule, an awakened bear will look for a new lair if the old one is not suitable for sleeping.

In that case, why does the brown bear hibernate again in winter, and not wait for spring? This is the easiest way to survive. But there are situations when, for various reasons, animals do not gain enough fat over the summer. They cannot lie in a den in this state until spring. Hunger makes them leave the lair and go in search of food. Roots, nuts, acorns and other edible things cannot be found under the snow. The only way to survive is to engage in predation.

Under such circumstances, the bear decides to attack weakened animals and even predators. He is ready to take prey from wolves and foxes, eat carrion. He can enter the neighborhood settlements, destroy apiaries, attack livestock and people. A meeting of a person with a starving rod-bear can end sadly - this must be remembered and understood.

Hibernation (hibernation) is a slowdown in vital processes and metabolism for a certain period of time. At the same time, body temperature decreases, breathing and pulse slow down, nervous activity and other body processes are inhibited.

It is difficult for many animals to get their own food in winter and they choose this way of survival in order to make it to warm days. Before hibernation, they feed with a vengeance, thus accumulating the energy they need during hibernation.

The winter hibernation of animals is a perfect way invented by nature to save their offspring from conditions that are unusual for their normal life.

There are a lot of animals that hibernate in winter. Most of them live in a temperate climate characterized by warm summer and cold winter during which it is difficult for them to find food. Some of them will be discussed below.

Bear

by the most famous representative animal world hibernating in winter is the bear. It should be noted that his hibernation is considered shallow. It's more of a snooze. Its body temperature does not become as low as in other animals that are in true hibernation. The same goes for his heartbeat. This means that if you try to touch him in this state, he can wake up very quickly and immediately begin to fight. Bears are animals that hibernate in winter, do not lose their orientation in space and time.

However, bears can remain in this state without touching food or water for up to seven months. This becomes possible thanks to the fat accumulated over the summer, the layer of which can reach 15 cm. In the summer, a bear does not just eat food, it brutally overeats. This process is somewhat reminiscent of fattening a pig, and is also equal to 30 full meals eaten per day by a person.

hedgehog

Hedgehogs are engaged in active life from 4 to 7 months, dividing this period into three stages: awakening, reproduction of offspring, preparation for long hibernation. With the onset of cold weather, they hibernate. The main reason for this phenomenon for hedgehogs is a lack of food, a secondary one is cold. They do not stockpile food for the winter as they feed on insects. Therefore, they have to stock up on fat in the summer season, and hibernate in the winter. In addition, their thermoregulation is imperfect, which leads to the need for prolonged winter stupor.

Gophers

Gophers in terms of hibernation are animals that are in a state of torpor for the longest time, to be more precise, up to nine months a year. Moreover, the cyclical nature of their stay in this state is noted. short active period life alternates with a long stupor, after which active life again occurs. It is replaced by prolonged hibernation, etc. This feature of their body is hereditary.

frogs

Frogs, in comparison with animals that hibernate or are in a stupor, can be in a state of deeper suppression of vital activity - in suspended animation. At the same time, their metabolism slows down as much as possible, and survival is carried out at the expense of internal energy reserves. Depending on the variety, frogs can hibernate in a hole dug by them, in crevices that they themselves cover with leaves, and also at the bottom of reservoirs.

The bats

Bats in winter, having found a suitable shelter, fall into a stupor for 7-8 months. Their sleep is interrupted every 2-3 weeks by awakenings to seek a warmer shelter and matchmaking, since winter for these animals is the period of reproduction.

Animals that hibernate also include rodents, Australian echidnas, Chilean opossums, hamsters, dormice, chipmunks and badgers.

I welcome you, dear friends, on the pages of the ShkolaLa blog! My name is Evgenia Klimkovich and I invite you to get another batch of useful and interesting information that will surely come in handy for preparing projects on the world around.

Today we’ll talk about which animals hibernate in winter.

Let's try to make our own list, TOP 5 sleepy animals.

We learn that winter sleep can be different.

And let's figure out why animals generally go to bed for so long? With this, perhaps, we will begin.

Lesson plan:

Why sleep so long?

There are two main reasons for this:

1. Getting cold.
2. Becomes hungry.

Animals - lovers of sleep live mainly in those places on the earth where it becomes quite cold in the winter season. Where snow falls, and because of this, the food that animals eat disappears. There are also in Russia.

And here the question arises. Why then do not all animals fall asleep? Here hares, for example, all winter jump through the forest in white fur coats. Or foxes, they don't go to sleep either.

Let's think.

What do rabbits eat? In summer, they eat herbs, berries, seeds, do not refuse mushrooms and young shoots of shrubs.

And in winter, when all of the above cannot be found under the snow, bunnies eat fallen tree branches, stems sticking out from under the snow, gnaw at the bark from trunks and chew dry grass that they manage to dig up.

Well, foxes, they hunt in summer and winter. The same hares, birds, mice are sometimes raided by chicken coops.

In addition, these animals change their coats for warmer ones closer to winter. And therefore it is difficult for them to survive in winter, but it is possible.

But the poor frog has no fur coat even in the summer, so she cannot survive the cold. This is where you have to go to sleep.

Some animals are able to travel long distances in search of food. So, for example, reindeer act when lichen reindeer, the main food of deer, runs out in their habitats.

And what about hedgehogs, for example? Until they run somewhere on their short legs, the winter will already be over.

Migratory birds flee from cold and hunger, flying to warmer climes.

And if gophers could fly, then they would fly after the birds. But they don't know how to fly. And so they also have to hibernate.

Did you know that animals sleep differently?

Types of winter sleep

Animals are all different and therefore they sleep differently in winter too. There are three types of winter sleep:

1. Hibernation.
2. Numbness.
3. Anabiosis.

hibernation

Hibernation is scientifically called hibernation.

Deep sleep, during which the animal changes all the processes in the body:

• heartbeat and breathing slow down;
• body temperature decreases;
• nerve activity is inhibited.

torpor

An animal that has fallen into a stupor is completely motionless, all vital indicators are sharply reduced in it. And often the body temperature of the animal is only slightly different from the ambient temperature.

Anabiosis

"Suspended animation" comes from a Greek word meaning "return to life"

Compared to torpor and hibernation, anabiosis is a deeper slowdown of all life processes. An animal that is in a state of suspended animation can be easily mistaken for a dead one, since the heartbeat and breathing are so slow that they can only be detected with the help of special equipment.

And now I present the top 5 well-known animals that hibernate. Let's start with the well-known brown bear.

Brown bear

With junior group kindergarten we all know that a bear sleeps in a den in winter and sucks its paw. Is it true? Well, at the expense of the paw, of course, this is fiction. But at the expense of sleep - the pure truth.

Moreover, the bear begins to prepare for his long sleep in the summer. He switches to an enhanced diet in order to accumulate more subcutaneous fat, the layer of which by autumn can reach 10 cm. Nutrients should be enough, because bears do not eat or drink during hibernation.

Sweet bears eat berries, roots, honey of wild bees. They like to eat fish or ants, as well as small animals.

But gaining fat isn't the bears' only concern before bed. We still need to find a place where to hibernate and equip a lair. For dens, bears choose places that are dry, warm and protected from possible intrusion of enemies.

A bear can make a lair:

• between the roots of trees;
• in the hollow;
• in an old anthill;
• in the dugout he dug.

And sometimes a bear builds a riding lair from tree branches, it resembles a large nest. In order to sleep comfortably and warmly, the bottom of the den is lined with moss and spruce branches.

When does the bear go to bed? Between November and December. The further north and colder the habitat of a bear, the earlier it climbs into its lair.

It is interesting! Pregnant bears and mothers with cubs go to bed first.

Well, bears wake up in the period from late February to April.

Sleep in bears is not so deep. He rolls from side to side in the den, you can wake him up. The she-bear wakes up in winter on her own in order to give birth to cubs and feed them in a cozy and safe den with her milk.

The body temperature of a bear during hibernation drops slightly, by only 5 degrees. And the heart beats at a speed of 10 beats per minute.

It also happens that the bear does not have time to prepare for winter. Does not gain the necessary supply of fat or does not equip the lair. Then he does not hibernate, and walks all winter through the forest, hungry, angry and very dangerous. Such a bear is called a connecting rod. And it's better not to meet him.

Do you want to know which of the animals besides the bear falls into winter sleep? Then read on)

Hedgehog

Do hedgehogs go into hibernation? That's right, they fall! Yes, not just hibernation, but a real stupor. At the same time, their body temperature drops from the usual 34 degrees to 1, and the number of heartbeats is reduced to a minimum.

In order to understand why the hedgehog sleeps in winter, you need to get acquainted with its diet. So, the favorite dishes of our prickly friend are:

• worms;
• slugs
• snails;
• frogs;
• beetles;

These are mainly insects that a hedgehog cannot prepare for the future, such as squirrel nuts.

And hedgehogs can eat snakes, even poisonous ones. Poison does not work on them. Scientists still cannot understand why this happens.

And due to the fact that there is no food for hedgehogs in winter, they go to bed. But first, prepare carefully for this. The hedgehog, like the bear, tries to eat more to accumulate fat, and is looking for a mink in some secluded place.

The hole must be about 1.5 meters deep. Otherwise, it will be very cold there and the hedgehog will simply freeze. The animal lines the bottom of the hole with dry grass and carefully compacts it. Then he clogs the entrance to the hole, curls up into a ball and falls into a stupor. The colder it gets outside, the deeper the hedgehog's numbness.

In this state, the hedgehog can stay up to 240 days without food and water. Well, when it gets warmer outside in the spring, the hedgehog comes out of his stupor and gets out of his mink.

Bat

Another big lover of insects, which is forced to hibernate due to lack of food and low temperatures in winter.

Some species bats like migratory birds, they fly to warmer climes, but most species remain to winter where they hunt in summer.

For their winter sleep, bats choose places where the air temperature, even in winter, does not fall below 7 degrees. Where the humidity is quite high and there are no drafts. These can be caves, mines, dungeons, hollow trees, attics and basements of houses.

The bat sleeps, firmly clinging its paws to the ceiling or wall.

Body temperature during this period drops significantly, as does the number of heartbeats per minute. Moreover, if it becomes too cold in the wintering place, or if someone disturbs the animals, they come out of hibernation and move to a more suitable place, where they fall asleep again.

Mice can stay in this sleepy state for up to 6-8 months.

It is interesting! It is not easy for bats to find a place to hibernate. Therefore, they remember successful places where they have already spent the winter and return there again.

Frog

And how do the well-known frogs survive the harsh winter? It is impossible to give one answer here. There are about 500 species of frogs. And they winter differently.

A bullfrog, for example, sinks to the bottom of a lake and burrows into the mud. It stays that way all winter. Her body temperature is very much reduced. She doesn't eat, drink or even inhale oxygen.

The question arises, how does a frog breathe? And why doesn't she die without air? The fact is that in this state the frog does not need to spend energy, and therefore it practically does not need oxygen. And the small amount of oxygen that is needed penetrates through the skin.

The bullfrog comes out of suspended animation when the ice on the surface of the lake melts. She just couldn't get out before. Well, since lakes rarely freeze to the very bottom, the frog stays all winter in a kind of thermos that does not allow it to freeze completely.

But not all frogs hibernate in water. There are those who make themselves a "bed" on the shore. Under snags, under stones. When winter comes, these frogs fall into deep suspended animation. It even happens that their body temperature drops below zero degrees.

Such an animal looks just like a dead one. But if you warm the frog, it will come to life.

Gopher

That's who loves to sleep, so it's a gopher. Squirrel relative. In winter, he falls into a stupor and can be in this state for more than 6 months. But the most interesting thing is that if there is little food for the gopher in summer, then it can lie down in summer hibernation.

Summer hibernation is scientifically called "estivation".

Ground squirrels feed on roots and leaves of plants, herbs, grains, seeds.

Gophers are excellent diggers. They dig holes for themselves up to 3 meters deep. Well, the length of such a mink can reach 15 meters. A nest is arranged in a mink, which is lined with grass and leaves. In this nest gophers give birth to offspring and sleep in winter.

The animals sleep, sitting on their hind legs, they lower their heads to the abdomen and cover themselves with their tails. And they sleep very deeply. Neither a loud sound nor a slight warming can wake them up.

To the touch, the sleeping gopher is completely cold, his feet turn white. If in a state of wakefulness the gopher inhales 150 times per minute, then in a stupor only 1 time in 8 minutes. And the body temperature drops very much, sometimes up to -3 degrees.

During hibernation, ground squirrels lose up to half their weight. Therefore, animals should definitely eat well before a long sleep in order to accumulate more fat and muscle mass. Otherwise, you may not survive the winter.

What can be added to the project to make it even more beautiful? For example, poems about wintering animals. Some you can hear in one of the episodes of the program "Visiting Dunyasha", which I found for you.

There are many more interesting things on the blog for you. For example, in you can get to know the owner of the mountains - the snow leopard, and you will find a lot of fascinating information about the cockchafer.

That's all for today!

I wish you happy learning!

Evgenia Klimkovich.

It's no secret that bears sleep in winter. This is perhaps one of the most famous and interesting features bears. But why do bears sleep in winter, and how exactly does this happen?

Causes of bear hibernation

Not all bears fall into hibernation, but only those that live in regions with long cold winters and a lot of snowfall.

The main reason bears sleep in winter is related to their diet. The fact is that bears are extremely large animals, the weight of some representatives reaches 700 kg.

Such a huge animal needs a lot of food. Despite the fact that the bear is practically omnivorous, with the onset of cold weather, it has great difficulty in obtaining food. Under a layer of snow, it is almost impossible to find plant food, and hunting in winter is much more difficult.

In addition, in cold weather, energy costs increase greatly, because the animal also needs energy for heating.

That is why, with the onset of cold weather, bears choose a safe place and go to bed. Hibernation can last from 4 to 6 months. All this time, the bear exists due to the reserves of subcutaneous fat accumulated over the summer.

During hibernation, the animal's body works differently. Energy requirements are reduced to a minimum, the breathing rate changes, which saves air in the den. In this state, the bear can sleep for many months without a threat to his life. Bear cubs appear in the bears' dens, and they spend the winter with her, feeding on her milk.

Bears are very light sleepers, so even the slightest noise can wake them up. A sleepy hungry bear is a serious threat to the tranquility of the forest. Rod bears are very aggressive and ferocious.

Not all types of bears sleep in winter. For example, in Arctic polar bears, only pregnant she-bears and females with cubs fall into hibernation - their energy consumption is very high. Males remain awake, eating nutritious seal fat and meat.

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Who waits in a dream not for winter, but for summer, which birds hibernate and other amazing facts.

In a fairy tale, because of the machinations of an evil sorceress, a beautiful princess pricked herself with a spindle and fell into a deep sleep for many years. No matter how magical fairy tales are, reality is more amazing than fantasy. Hibernation is one of the adaptation mechanisms that animals have developed to survive in adverse conditions. This is not just a deep and prolonged sleep, it is rather a "little death". Body temperature drops, sometimes even below 0 °C. The metabolism slows down dramatically, sometimes rearranging itself to help the animal cope with prolonged exposure to low temperatures. Introducing ten hibernating animals that are just as good as the fairy-tale sleeping beauty.

alpine marmot “Sleeps like a groundhog” - they say about a soundly sleeping person. This is both true and false at the same time. Groundhog really belongs to those animals that prefer to wait out the winter, plunging into sweet dreams. Hibernation lasts about six to seven months, during which the groundhog does not eat or drink, managing exclusively with internal reserves accumulated over the summer. Marmots hibernate in burrows with the whole family: in the center, where it will be warmest, young individuals go to bed, and adult animals are located around them. Groundhogs usually wake up at the same time every two weeks to clean up, and also fall asleep again at the same time. But if it gets very cold, the animals wake up outside the schedule in order to raise the air temperature in the hole with the heat of their bodies.

american spadefoot These tiny amphibians that live in arid regions North America, can be easily mistaken for ordinary frogs, if not for the amazing structure of the limbs. Unlike other animals hibernating in winter, spadefoot spend the hot months in sweet dreams, when all living things suffer from a lack of moisture. They hide underground, burrowing into soft soil at the bottom of ponds and streams. To do this, in the process of evolution, the spadefoot acquired hard growths on the legs, thanks to which they turned into an excellent working tool, and the amphibians themselves got their name.

Gray mouse lemur Located in the tropics, Madagascar is hard to suspect in such a harsh climate that the animals were forced to hibernate. Nevertheless, the gray mouse lemur is so gentle that it resorts to this adaptation mechanism, completely atypical for primates, during the relatively cold and dry Madagascar winter. These animals prefer to get food alone, but to rest - in the company of their own kind. Interestingly, only females gather in groups for hibernation, but males hibernate in splendid isolation.

hummingbird Hummingbirds are undoubtedly the “most-most” among birds. The smallest birds can fly backwards, and flap their wings so fast that they make a buzzing sound, just like insects. Hummingbirds feed on nectar and small insects that they get by hovering over the flower like butterflies. These birds are distinguished by a truly high-speed metabolism: they need to eat every 20 minutes. At night, this becomes impossible, and in order to survive the night, hummingbirds do not just fall asleep, but fall into a state of suspended animation: the body temperature drops from 42 ° C to 16 ° C, the heart beats at a frequency of 20 beats per minute instead of 500. Life in a tiny body freezes to be reborn with the first rays of the sun.

American wood frog In winter, forest frogs, living in Canada and the northern United States, are more like figurines skillfully carved from motley jasper, covered with an openwork lace of ice and snow. It is hard to believe that they will come to life, one has only to warm them up. The main threat that cold poses to animals is that fluid in the body turns into ice crystals that destroy cells. Warm-blooded animals solve the problem simply by keeping their body temperature above 0 °C, but cold-blooded animals had to turn into real chemical plants for the production of cryoprotectants. Thus, on the eve of winter, the American forest frog not only increases the level of urea in the blood, known for its antifreeze properties, but also accumulates glycogen in the liver. When it gets cold, glycogen starts to turn into glucose. The frog is literally soaked in sugar syrup, which lowers the freezing point (as you know, jam does not freeze). Thanks to these tricks, ice forms only around the cells, and not inside them, which allows forest frogs to successfully endure low temperatures.

Siberian salamander Another amphibian that has learned to wait out the cold in a frozen state without harming itself. Only in this case, nature decided to use not glucose as a cryoprotectant, but glycerin, the substance from which the first antifreezes for cars were made. The newt-like salamander is the only amphibian that has mastered the permafrost zone. On the eve of winter, the liver of the salamander begins to intensively produce glycerin, which permeates all tissues. Thanks to this, the amphibian is able to hibernate for months and even years. So, scientists successfully thawed a salamander that had lain in the frozen ground for more than 90 years.

Brown bear Perhaps the most famous dormouse from the world of mammals. Strictly speaking, brown bears do not hibernate, more like death, but plunge into a deep winter sleep. The bear's body temperature drops slightly, the bear tosses and turns, and the bear even wakes up to give birth to cubs. For this reason, although biological processes are greatly slowed down, metabolism still occurs, and waste is generated as a result. In a normal situation, this is not a problem, but not in a cramped and fenced off from the world lair, in which it is necessary to maintain cleanliness. Recent studies have shown that brown bears have found an ingenious way out of the situation by developing a recycling mechanism. Urea from the bladder goes back into the bloodstream and returns to the intestines, where it turns into ammonia, which is already used in the liver to form amino acids - the basis of proteins. A good help to the thick layer of fat that bears work up in preparation for winter.

hedgehog Ordinary hedgehogs hibernate only in places with a harsh climate. Moreover, if in females the duration of hibernation depends on the air temperature and the availability of food, like in other animals, then males are more sensitive to the level of testosterone in the blood. A decrease in the level of this hormone provokes hibernation, and an increase - a return to an active state. At the same time, in hedgehogs, the testosterone level is tied to the level of melatonin, which, in turn, depends on the length of daylight hours. However, it is not yet entirely clear how hedgehogs, being deep underground, assess the situation on the surface: daylight hours, ambient temperature, and the availability of food. Perhaps that is why they take breaks in hibernation.

Winter colds make their own adjustments to the behavior of many animals. Bears, raccoons, hedgehogs, marmots, badgers, jerboas hibernate before the onset of heat, but there are also those who do not sleep in winter, trying with all their might to survive in difficult natural conditions. What animals do not sleep in the forest in winter? These include almost all the wild animals we love from children's fairy tales: squirrels, hares, foxes, wolves, etc.

Most forest dwellers begin to prepare for winter even before the onset of cold weather. Some of them stock up on food in advance, change their coat color, and improve their homes. Squirrels are such prudent animals. Their preparation for frost begins in the warm season. In winter, squirrels live in nests, which they arrange in empty hollows or on branching branches. Rodents stock up on nuts, acorns, cones and mushrooms in advance, so that in the difficult winter time they and their cubs have something to eat. They hide their food preparations under old stumps, moss, in empty hollows and tree roots. Squirrels' dwellings are insulated with dry straw, leaves and moss, which are also stocked long before frost. The animal spends the winter in the nest, leaving it only to take food from its hiding places. Before a cold snap, the squirrel coat changes its color from red to gray, thanks to which its owner is not so noticeable against the background of white snow. The brightened coat becomes thicker and warmer, helping the squirrel to adequately survive the cold season. The inhabitant of the trees plunges into a short hibernation only in severe frosts, the rest of the time it deftly jumps along the branches, becoming a real decoration of the deserted forests and parks.

Unlike the industrious squirrel, the hare does not prepare for winter. In the cold season, he has a hard time, because he does not have his own warm mink or den, where he could wait out severe frosts or hide from enemies. Before winter, hares molt, changing the color of their fur coat from gray to white. This allows them to become invisible to hungry predators roaming the forest in search of prey. To make it more comfortable for the animal to move on cold snow and slippery ice, the pads of its paws are covered with wool. The main problem of the rodent in winter is the search for food. He does not make any food stocks, therefore, with the onset of frost, he has to eat only what he can find. The main food of hares in the cold months is dried and frozen berries preserved from autumn, dry grass, bark and tree branches. In winter, hares prefer to stay closer to human habitation: here they have the opportunity to eat hay, leftover animal feed and bark. fruit trees. During the day, rodents prefer to sleep, and go out in search of food at night, when they are least visible to predators and hunters. Hares do not have a warm dwelling; they use minks, which they dig for themselves in snowdrifts, as shelter for them. Thick wool saves them from freezing, and quick paws from enemies.

Those who do not sleep in winter often have a hard time, because not all animals manage to survive the snowy and hungry months. The constant search for food is not the only test for animals in winter forest. An equally important problem for them is hunters, whose numbers increase sharply with the onset of the cold season. But, despite the difficulties, animals manage not only to find food for themselves and hide from enemies, but also to prepare for the birth of offspring.

The fox feels like the mistress of the forest in winter. The cheat does not change the color of its fur coat, as squirrels and hares do. A thick and warm undercoat, which begins to grow back in summer, helps her survive severe frosts. The paws of the red predator are covered with wool, thanks to which she can calmly step on the snow and not freeze. Foxes do not tend to store food, so the search for food becomes their daily problem. They deftly find mice under the snow, often make their way to the villages and steal chickens, geese and other poultry from people. Often the hare becomes the prey of the beast. The fox does not have its own housing, it spends the night right on the snow, curled up in a ball and covering its nose with a fluffy tail. The mating season is from January to February. Several males can take care of one female at once. To gain her favor, they arrange real fights. The strongest male becomes the chosen one of the female. After mating with him, the fox begins to choose a place for a hole in which she will give birth and raise future offspring. To protect their cubs from enemies, they equip minks on the hills, from where the whole area is clearly visible.

What animals do not sleep in winter yet? Of course, wolves are the most dangerous forest predators. On the eve of winter, they acquire long and thick hair, which allows them to endure the cold. The wolf does not have a hole or lair. He sleeps in the snow, covering his tail and paws with his own tail. In winter, wolves spend the day sleeping, waking up and hunting after dusk. They see perfectly in the dark and have excellent hearing, allowing you to hear the slightest rustle. In search of food, the wolf is ready to run tens of kilometers. He preys not only on small animals, but also on large animals, the size of which exceeds his own. Wolves go hunting both alone and in a pack (coordinated actions of all its participants help to get a large beast). Being very hungry, they become promiscuous and often attack people and dogs. In the absence of large prey, these predators are content with small rodents. In order to survive, wolves are ready to physically eliminate competitors. It is not uncommon for them to strangle foxes in order to take possession of their prey. Wolves not only hunt in packs, but also live in them, because it is easier for them to survive in difficult conditions. They lead a nomadic life and only at the end of winter they equip themselves with a lair for the birth of offspring.

It is hard in the cold season for wild boars. If there are no heavy snowfalls and severe frosts in winter, these animals feed on small rodents, the remains of acorns, roots and leaves. In severe cold, when the ground freezes, they often have to starve. Because of this, wild boars are greatly weakened and often become prey to wolves. To protect themselves from danger, they sleep in a lair built from fallen leaves during the day, and go out in search of food at night.

Winter is the most restless time of the year for the inhabitants of the forest. During this period, animals have to work hard to get their own food and be extremely careful not to fall into the clutches of predators and not become the prey of hunters. The only exception to this rule is the squirrel, which stores food in advance and equips its nest in such a way that it is cozy and warm in winter.

Hibernation.

Hibernation is not just an adaptation of animals to severe trials. For many animals, this is the only chance to survive the winter and avoid starvation.

The bear is a real furry giant. He is very big and strong.
The bear loves to eat various cereals, rhizomes, nuts and berries. The bear loves to fish. For hours he is ready to stand motionless on the shore of a reservoir and wait for his prey. The bear is ready to endure many hundreds of bee stings in order to taste his favorite delicacy - honey.
But all this diversity in winter is practically non-existent. And our "predatory vegetarian" hibernates in winter.
Before falling into hibernation, the bear builds a lair for itself. Bears build their dwelling from branches and trunks. He tries to escape into the deaf thickets. But before falling into hibernation, the bear eats a lot of fat. Did you know that the bear does not sleep all winter? It happens in winter that the bear wakes up and goes out for a bit to wander, and then comes back and falls asleep again. In winter, bear cubs are born to a she-bear. And like any caring mother, the she-bear takes care of her babies.

What other animals hibernate?
A chipmunk, having made a full hole under a supply tree, falls asleep "without hind legs." You can pick him up and try to wake him up, but your attempts are useless. This "sleep" is not to be woken up.

A hedgehog that has gained fat prepares a cozy nest for itself in deep pits or minks. The hedgehog sleeps curled up in a ball in winter. But he doesn't fall asleep right away. At first, the hedgehog often wakes up, and then falls asleep again. Each of his dreams is getting longer and longer.

Bats long before the arrival of winter found a secluded cave or attic. And from time to time they wake up and fall asleep again. During periods of wakefulness, bats can look for food.

Wild animals not sleeping in winter.

Long before the onset of cold weather, animals grow warmer and thicker wool. Many of them create stocks of food and insulate their homes.
One of these thrifty animals is the squirrel. Even in warm weather, she made herself a house in a hollow or on a strong bough. The squirrel's dwelling is insulated with dry mosses, hay and leaves. The squirrel's house must have two entrances. For the winter, the rodent stocks a lot of nuts, acorns, cones and mushrooms.

The squirrel hides its supplies throughout the forest: under old stumps, in empty hollows and tree roots. The squirrel leaves the house only when it is necessary to pick up supplies from the cache.

Elk is a real giant. He needs a lot of food. In winter, moose can live alone or together. What do moose eat in winter? Moose love to eat the bark of young aspens, shoots of young pines. Moose have very strong and large teeth. When there are no young shoots in the area, the elks grind the rough bark of old trees with their teeth. Moose rest buried in the snow.
Large ungulates have a hard time in winter. But it is even more difficult for boars. If the winter is mild, without snow, then the wild boars get different roots and leaves. They can also eat rodents. In severe frosts or heavy snowfalls, wild boars often starve, become weak and defenseless against predators. For their salvation, wild boars gather in flocks and only go out at night in search of food.
Wolves are the most dangerous forest predators. Their coat becomes thick and long in winter. Such wool helps to transfer the wolf winter cold. And even in severe frosts, the wolf can sleep in the snow, covering its nose with a fluffy tail. As soon as it starts to get dark, the wolves come out to hunt. Wolves travel very long distances in search of food. Sometimes many tens of kilometers. They hunt animals of any size alone or in packs. The coordinated actions of the whole pack helps the wolves survive.

The true owner of the forest in winter is the fox. The red-haired cunning woman walks in a fur coat of the same color in winter and summer. Only the coat becomes dense with a thick undercoat. The fox walks on the snow without falling through, thanks to the paws covered with wool. Foxes live in burrows. But many cheats sleep right on the snow. They cover their nose with a large fluffy tail. The fox does not make supplies. So every day she goes hunting. Often foxes make their way to villages to steal poultry. Quite often the fox catches hares. But the main food of foxes in winter are mice.
For the winter, mice stock up on seeds and dry the berries. They are very voracious and every day they need a lot of food. In snowy winters, mice dig long passages in snowdrifts. Mice love to hide in haystacks and move into human barns and houses.

Beavers are hard workers. A friendly family builds its solid hut all autumn, felling aspens, willows and other trees. The entrance to the hut is always arranged under water. The enemy won't pick up. And the water is warmer than the air in winter.

In winter, the white hare changes its gray coat to a white one. In a brown hare, the color of the fur coat becomes only slightly lighter. In winter, the paw pads of hares are covered with wool. Therefore, the paws of hares do not freeze much. And also, therefore, hares can run away from predators on slippery ice. Unlike many other rodents, it does not store supplies. It feeds only on what it can find in winter: small twigs and young bark of willow, birch and aspen. A real delicacy for a hare is frozen berries. Therefore, in winter it is very difficult for him. During the day, hares hide from predators in burrows dug in snowdrifts. Hares come out to eat at night. They sleep in the snow.
Winter is the most difficult time of the year for animals. The life of animals in this harsh time is difficult and dangerous.

You should know that not all animals hibernate during the winter. Animals that do not hibernate continue to lead an active lifestyle.

Animals, when hibernating, can sleep for five to eight days. At the same time, they curl up into a ball, for less heat loss. While the animal sleeps, its organs work, just as in normal life.

After rest, to restore strength, the animal must eat.

An animal may appear dead when it is hibernating - this is because it is completely motionless. Breathing and digestion slow down, the heart works slowly. Therefore, the body temperature reaches 10 degrees Celsius.

In this state, the animal uses its fat reserves accumulated over the summer.

If the animal adapts well, then it can spend several months in hibernation - for example, bears and hedgehogs sleep for so long.

So why do animals go into hibernation?

They do this in order to make up for the temporary lack of food. In winter, the bear will not find small mammals and fruits in any way, and the hedgehog will find insects for food.

The place where the animal hibernates is of great importance. A hedgehog digs a hole under the roots of trees, where it winters, and bears like to sleep in dens where there is no wind and it is not cold. A bear can die from lack of food if it is awakened during hibernation. You should also know that in order for the bear to return to hibernation again, he needs a lot of strength and energy, which he may not have in winter.

All animals, without exception, prefer rest, night or day, to active wakefulness. They especially like to fall into or catalepsy. In countries with a cold and temperate climate, the habitual pastime of animals is a six-month hibernation.

Hibernation is a hereditary reaction of living organisms to temperature changes, which was formed millions of years ago.

It was possible to survive these drops only by learning to regulate their own temperature when cold or hot came on. The life of an animal depended on the ability to sleep through a difficult time.

So nature took care of her creatures - this skill will come in handy if the climate on Earth changes again.

Hibernation is characterized by slowing down and metabolism in animals during periods when food is inaccessible, which means it is impossible to maintain activity and a high level of metabolism.

Preparing for hibernation

Preparing for a long sleep, animals accumulate nutrient reserves, their weight due to fat can increase by 40%, and also store food. Nutrition in the preparatory period is rich in fatty acids, which increase immunity and resistance to prolonged torpor.

Rodents are located for the winter in families or alone. The burrows they burrow can stretch inward for three meters or more. Stores of grains, nuts and seeds are arranged in them to maintain vitality.

Shelter (hollow, cave, burrow) is selected taking into account safety, protection from predators, and microclimate: the temperature of the shelter should be slightly above zero, even with severe frosts outside.

Animals according to the method of maintaining body temperature are divided into:

• endothermic that preserve heat regulation at the expense of internal resources. These include all warm-blooded organisms: mammals, birds.
• ectothermic, their temperature depends on the environment. They include cold-blooded organisms (reptiles, amphibians, fish).

Types of hibernation by duration:

• per diem(in bats and hummingbirds).

This type of deep sleep can occur in any season, in both mammals and birds. Physiological processes are less slowed down than during seasonal hibernation. Body temperature usually drops to 18°C, in rare cases - below 10°C, metabolism is reduced by a third.

• Seasonal- winter (hibernation) or summer (estivation).

Winter (hibernation) hibernation is not a homogeneous state and is interrupted for short periods of "warming up" of the body: the body temperature briefly rises and energy exchange increases. Body temperature usually drops to 10°C and below. In long-tailed ground squirrels, it drops to 3°C. Metabolism is 5%, and sometimes slows down to 1% of the normal state.

• Irregular, in squirrels and raccoon dogs, upon the onset of adverse conditions suddenly.

By the way, a person can also suddenly fall into a stupor, but at the same time retain consciousness. This is how a severe mental disorder of motor function manifests itself.
why do animals fall

Hibernation

Winter is a difficult test for many animals. Migratory birds travel great distances to reach warmer climes. Animals that cannot leave cold climates adapt to the change of seasons in their own way: they sink into a dream-like state.

When the ambient temperature drops to five degrees Celsius, beetles and butterflies, toads and frogs, lizards and snakes, bears and hedgehogs go to bed. Infusoria, amoeba and algae, gathering in a large ball, wrap themselves in a protective shell.

Carp and carps burrow into the mud. Bats doze in caves for six months, hanging upside down.

Aestivation

Summer hibernation or diapause (temporary cessation of development, state of physiological dormancy) ensures the survival of organisms during dry periods of the year. Fish sleep, wrapped in silt at the bottom of dried-up reservoirs. Tortoises and rodents, deprived of food, fall asleep until winter, when swamps and plants dry up from the heat.

Some inhabitants of the tropics also tend to fall asleep for a long period: African hedgehogs sleep for about three months, and the insectivores of Madagascar for about four.

The hibernation record is broken by rodents. For nine months in a row, the sandstone gopher sleeps. Falling into summer hibernation at the end of July, the animal passes into winter without waking up.

Periodic awakenings.

Some animals wake up from the sleep state from time to time. Scientists do not know exactly the purpose and cause of this behavior. Awakening can last from several minutes in small organisms to several hours in large ones.

So many living organisms fall into hibernation that it is very difficult to list them all. Soviet zoologist N.I. Kalabukhov claimed that there are many more animals that are in a state of stupor in winter than those that are awake.

Physiology of hibernation

Body temperature. Sleeping animals are only a fraction of a degree warmer than the surrounding air. The body temperature of the dormouse drops from 38 degrees to 3.7 (ten times!). In some species, it can drop to zero and even to minus five degrees Celsius.

Dallium fish, a rare warm-blooded fish, falls asleep when the waters of Chukotka freeze through. If a dallium frozen in a piece of ice is put in warm water, then as soon as the ice melts, the fish will come to life. Due to the unique glycerin-like impregnation, ice crystals do not form in the tissues of dallium, which can break cell membranes.

The hypothermic state of all others is manageable. Brain regulators, led by the tireless hypothalamus (the part of the brain responsible for the constancy of the internal environment of the body), turn on fatty heating in time so that the body temperature does not fall below a critical level.

Metabolism during hibernation decreases in animals to 10-15% of the norm.

Breath in sleeping mammals it decreases by 40 times. In many species, it alternates: rapid superficial is replaced by apnea (lack of breathing) lasting more than an hour, which causes oxygen starvation.

gas exchange- decreases by 10 times. The hedgehog, curled up in a ball, takes a barely perceptible breath just once a minute.

brain activity is preserved only in the hippocampus, the department adjacent to the hypothalamus.

A heart slows down the frequency of contractions per minute to 5-10 beats, in a hedgehog it beats even at zero body temperature. This is surprising, because in animals that do not hibernate, the heart stops at a 15-degree body temperature.

Blood pressure decreases slightly, from 20% to 40%, since the viscosity of the blood increases due to a decrease in temperature. Due to the increased viscosity of the blood, the heart is better supplied with "brown fat", a source of energy.

Hormonal system before hibernation, it is rebuilt to a new rhythm: the animal accumulates fat, enzymes, vitamins, especially vitamin E, which inhibits metabolism. In summer, animals grow fat, increasing their weight by three times by autumn, and thin and weakened wake up in spring.

An interesting fact:

the hibernation of the brown bear, squirrel and prairie dog is not real - they fall into a state of superficial torpor. Their metabolism slows down a little, body temperature, pulse and breathing correspond to the level typical of normal sleep.

Most of them hide in their hiding places and support their existence on the food and fat reserves they have collected for the occasion.

The consciousness of a bear during hibernation does not turn off, it is easy to wake him up.

Pros and cons of hibernation

The undoubted pluses include a reduction in the energy consumption of the animal: it consumes only 15% of the energy that it would need to maintain normal temperature body in winter when awake.

Within 4-7 months they can exist due to the accumulated reserves of fat and other nutrients.

Disadvantages: the ability to die from desiccation or exhaustion, the development of skeletal muscle atrophy, decreased immunity, with extreme low temperatures freezing, defenselessness against predators is not excluded.

Research by scientists hibernation mechanisms have a practical purpose: the formula of chemicals that immerse animals in a long hibernation ioz, will allow to carry out surgical operations, cooling the human body to the required temperature.

Sources: A. Borbeli "The Secret of Sleep", "Three Thirds of Life" A.M. Wayne, ru.wikipedia.org, Collier's Encyclopedia (Open Society. 2000).

The following beautiful video is about birds that do not fall into hibernation in winter, but travel thousands of kilometers to get to warm countries:

Elena Valve for the Sleepy Cantata project