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How do bears hibernate?

Almost all species of bears hibernate , spending most of the winter in their dens, sleeping in a dormant state, awaiting the arrival of spring, the heat and the flowering of nature. The phenomenon has been studied by scientists. How do they manage to survive for so many months without eating or drinking or urinating, doing nothing but sleep?

You may also be interested in: What animals hibernate and why

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The key: a protein

The Washington State University team has used an echocardiogram and analyzed heart tissue from bears and found that proteins in the heart change to match the slow rate of heartbeat when bears hibernate. Contractions of the heart muscle are controlled by a protein called myosin. This protein comes in two varieties: alpha, which produces a faster but weaker heartbeat, and beta. When they hibernate, the muscle in the left atrium of the heart of bears produces more alpha protein, so that the beat is weaker and does not damage the heart.

This discovery could help physicians treat coronary heart disease.

Hibernation of the Bear

An article has been published in the journal Physiological and Biochemical Zoology that explains what happens to the heart of bears when they hibernate and that explains the phenomenon. The heart of bears undergoes some changes in grizzly bears ( Ursus arctos horribilis ), the species of bear that has been studied by scientists.

This particular species hibernates between five and six months a year. During that time, the heart rate drops from normal, a speed of about 84 beats per minute, to 19 beats per minute. Many animals, including humans, would be on the brink of death if their heart rate dropped to that level. But bears live. They don’t just live, they need it to get through the winter.

Such a slow heartbeat , logically, causes the blood flow to be altered, with fatal consequences. For example, the atria and ventricles could become flooded. In a person, these cavities would expand and the muscle would be weaker and less efficient. Eventually, heart failure would occur and death would ensue. However, this is not what happens to bears. Now they have discovered why.

If you want to read more articles similar to How do bears hibernate? , we recommend that you enter our Wild Animals category .

Maria Anderson
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Hello, I am a blogger specialized in environmental, health and scientific dissemination issues in general. The best way to define myself as a blogger is by reading my texts, so I encourage you to do so. Above all, if you are interested in staying up to date and reflecting on these issues, both on a practical and informative level.