In the spring, bears wake up throughout the Northern Hemisphere. Still, since last fall they had no poppy dew in their mouths.

Why is hibernation necessary?

Snowy winter is not a gift for most animals. Food disappears from the frozen ground. Days become short and cold, nights long and even colder.

The search for food requires a large expenditure of energy, which, perhaps, cannot be made up for by the food found (if you can find anything at all). Some animals, such as migratory birds, just fly south, fleeing from winter. Others endure the cold. Many die. And some animals, such as hummingbirds, arctic squirrels and brown bears, hibernate. Falling into hibernation, animals reduce the body's need for energy, reduce it to a minimum.

Interesting fact: hibernating animals reduce their heart rate to one beat per minute.

What is the difference between hibernation and sleep?

If hibernation was an ordinary dream, then everyone could fall into it. You walked into the courtyard in December, put up a tent, and even sleep in good health. In April, wake up, stretch and go home for breakfast. It’s clear that you are not able to do this: firstly, you won’t be able to sleep for so long, secondly, after a few days you will need to drink water, and thirdly, you will simply freeze. But the fact is that hibernation is a condition that is different from normal sleep. This is a special survival mechanism that allows you to lower body temperature and reduce heart rate in order to reduce the body’s energy expenditures during cold and deprivation.

According to scientists, there are animals that fall into true hibernation, such as gophers and other small animals, and animals such as bears that fall into shallow hibernation. A small animal, falling into true hibernation, quickly reduces the heart rate from 150-300 beats per minute to 7 beats per minute or less. In California gophers, heart rate may drop to one beat per minute. The body temperature gradually decreases to very low numbers, sometimes almost to 0 degrees Celsius, although the initial body temperature of small rodents is practically no different from ours and is about 35 degrees Celsius. In short, the temperature becomes the same as the temperature in the mink.

Hibernation process

If hibernation has come, then the animal is as if dying for the outside world. You can step on a hibernated animal, throw it into the air, and catch it, and it will not even squeak. However, small sleeping animals do not remain "sleepy" all winter in a row. Every few weeks, and sometimes even once every four days, these animals wake up from hibernation, just like people "leave" after anesthesia. They drink water, even eat a little, satisfy their natural needs.

Interesting fact: every few days or weeks, hibernated animals wake up to eat, drink and relieve their natural needs.

They can remain awake for up to a day, then return to their anabiotic state again. During hibernation, such animals lose weight up to 40 percent.

Hibernation in bears

In contrast, such dramatic changes in the body do not occur in bears. Body temperature does not drop so sharply, pulse rate decreases slightly. They are quite oriented in space and time. Hibernating bears better called nap. However, there are experts who believe that it is the bears that fall into true hibernation, as they can oversleep all winter, and even more, never waking up.

The bear can lie in the den without touching either food or water for seven months. Take, for example, a brown bear, it is as warm-blooded as we are.These creatures every year "wave the world" for four months. Sometimes they retire to caves or make their own lairs in the hollows of trees.

Some bears just rake leaves and lay down on the ground. During the winter, sleeping bears gradually fill up with snow. How do bears endure so much time without food and water, and besides, in severe frost? The bear somehow undergoes radical restructuring of its body, the cells begin to spend energy very carefully, maintaining the vital functions of the body at the required minimum level. In the summer, the bear doesn’t just eat a lot, it overeats. Summer for him is a celebration of overeating. During the season, a layer of fat grows up to 15 centimeters thick on a bear. The whole process of summer feeding a bear is very similar to fattening a fat pig. A bear consumes up to 20,000 calories per day. This is the same if you ate 10 breakfasts, 10 lunches and 10 dinners per day.

Interesting fact: it’s better not to touch the bear sleeping in the den, it wakes up instantly and is very dangerous at this moment.

Fat is the key to survival

Fat is the key to bear’s survival during hibernation. When a bear prepares for winter, its body undergoes some changes. In the normal state, when the bear is sleeping, its heart rate is 40 beats per minute. As the bear goes into hibernation, the heart rate reaches eight beats per minute. Body temperature decreases by 5 degrees Celsius. In this sense, the bear is far from gopher, but if the temperature dropped by 5 degrees Celsius in humans, it would cause a lot of trouble to the family doctor.

A hibernated bear costs very little energy to sustain life. Instead of getting it with food, the bear slowly burns the fat accumulated over the summer. When fat is completely burned, carbon dioxide and water are formed. During hibernation, the bear does not urinate, that is, practically does not lose water. Therefore, even without water, the bear is able to tolerably maintain its water balance by burning fat.

Since the bear uses such metabolic methods for hibernation that they cannot use, say, gophers, their “sleep” is not as deep as that of small rodents. The body temperature of the bears never drops to ambient temperature, and the pulse rate is never very small. What can be added to what has been said? Do not try to touch a bear hibernated, you can suffer greatly from this. Such a "sleeping" bear only looks harmless and quiet, but in fact he is quite oriented in the situation and ready for battle. He often even has his eyes open.

The bears, as they say in the people, have a disgusting character, and when they are hungry, they are able to eat each other. Therefore, a sleeping bear must keep its ears at the top of the head so that it does not eat an angry and hungry bear roaming the forest - a connecting rod. If the body temperature of the bear fell to ambient temperature, and he would go into deep hibernation, he would put himself in great danger. Therefore, the bear, as it were, came up with a special form of hibernation, more adapted to real life conditions than the true hibernation of rodents.

Hibernation for people

During the summer, the bear walks on a thick layer of fat, consuming 20,000 calories per day. Scientists studying the mechanisms of hibernation of animals, would like to find and extract any benefit for humans from their research. For example, if it were possible to isolate those chemicals with which animals are immersed in hibernation, then these substances could be used to cool the human body during some surgical operations.