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Well, it stops you from freezing to death, or starving to death, in winter - that must be an increase in life span.Some animals I believe will optionally hibernate, depending on how cold the winter is - I'm not sure if it makes a difference to life expectancy.Ofcourse, one problem is that life expectancy in the wild is rarely down to old age - it is usually down to predation - when an animal gets old enough that it can't run very fast, then something catches it and eats it. Only very big animals (such as elephants, of blue whales) that are too big to be brought down, no matter how slow they are, might be able to avoid predation in old age, but they do not hibernate.
One animal that some famously consider a hibernator is the bear, although bears do not go into "true hibernation". During a bear's winter sleep state, the degree of metabolic depression is much less than what is observed in smaller mammals. Many prefer to use the term "denning". The bear's body temperature remains relatively stable (depressed from 37 °C to approximately 31 °C) and it can be easily aroused. In contrast, hibernating ground squirrels may have core body temperatures as low as -2 °C. Some reptile species are said to brumate, or undergo brumation, but the connection to this phenomenon with hibernation is not clear.
Erika Nordby, a toddler of 13 months in Edmonton, Alberta, wandered outside her family home on February 23, 2001. The outside temperature was -24 °C (-11 °F). When she was found, her heart had stopped beating for two hours and her internal body temperature had fallen to 16 °C (61 °F). Other sources say there was a slow pulse of 30 beats per minute but no blood circulation when paramedics arrived. In either event she was clinically dead. She suffered severe frostbite, yet required no amputation and made a full recovery.In October 2006, a Japanese man, Mitsutaka Uchikoshi, was believed to have been in a "denning"-like state for three weeks. He had fallen asleep on a snowy mountain and claimed he had only woken up after being discovered 23 days later; doctors who treated him believed his temperature had fallen to 22 °C (71 °F) during that period.
In 2005 it was shown that mice can be put into a state of suspended animation by applying a low dosage of hydrogen sulfide (80 ppm H2S) in the air. The breathing rate of the animals sank from 120 to 10 breaths per minute and their temperature fell from 37 °C to 2 °C (98.6 °F to 35.6 °F) above ambient temperature (in effect, they had become cold-blooded). The mice survived this procedure for 6 hours and afterwards showed no negative health consequences.Such a hibernation occurs naturally in many mammals and also in toads, but not in mice. (Mice can fall into a state called clinical torpor when food shortage occurs). If the H2S-induced hibernation can be made to work in humans, it could be useful in the emergency management of severely injured patients, and in the conservation of donated organs.As mentioned above, hydrogen sulfide binds to cytochrome oxidase and thereby prevents oxygen from binding, which leads to the dramatic slowdown of metabolism. Animals and humans naturally produce some hydrogen sulfide in their body; researchers have proposed that the gas is used to regulate metabolic activity and body temperature, which would explain the above findings.In 2006 it was shown that the blood pressure of mice treated in this fashion with hydrogen sulfide did not significantly decrease.
Erika Nordby, a toddler of 13 months in Edmonton, Alberta, wandered outside her family home on February 23, 2001. The outside temperature was -24 °C (-11 °F). When she was found, her heart had stopped beating for two hours and her internal body temperature had fallen to 16 °C (61 °F). Other sources say there was a slow pulse of 30 beats per minute but no blood circulation when paramedics arrived. In either event she was clinically dead. She suffered severe frostbite, yet required no amputation and made a full recovery.In October 2006, a Japanese man, Mitsutaka Uchikoshi, was believed to have been in a "denning"-like state for three weeks. He had fallen asleep on a snowy mountain and claimed he had only woken up after being discovered 23 days later; doctors who treated him believed his temperature had fallen to 22 °C (71 °F) during that period.[quote/]