Have you ever wondered how hibernating animals are able to stay warm during winter and not freeze to death? Typically, animals will grow a thicker layer of fat during hibernation season, which helps to trap heat inside their bodies. Scientists have been conducting research, however, to gather more facts about how small mammals in particular stay warm during hibernation, and some of these new studies may reveal some answers.
According to Elena Gracheva, a neurophysiologist at Yale University School of Medicine, human and mouse (non-hibernators) neurons flare up quickly in response to cold, while hibernating mammals such as ground squirrels and hamsters have less activity when exposed to cold temperatures. According to Jason Bitell, an author for National Geographic, Gracheva had hypothesized that hibernators might have fewer cold sensors in their nervous system; so they conducted a study to find out. They took the mammals afore mentioned, (the hibernating ground squirrel and hamster, and the non-hibernating mouse) and found they had blatantly different reactions to cold temperatures. The scientists compared the mammals on two different platforms. One platform was set above 80 degrees Fahrenheit and the other would differ from above 80 degrees down to the freezing point of 32 degrees Fahrenheit. What they discovered was that the hibernating animals explored both platforms, while the non-hibernating mice gave the cold platform a very brief interaction and didn’t venture back that way again. Ultimately, it appeared that the cold temperature hardly had an impact on the hibernators in comparison to the mice.
Contrary to Gracheva’s hypothesis, the scientists found that all mammals partaking in the experiment had the same amount of cold sensing cells. However, the hibernator’s sensitivity to their cold sensors compared to the mice appears to be turned down much more than the latter. This is one of many changes, such as reducing body temperature and heart rate, hibernating animals must undergo in order to conserve energy and survive the winter. It seems that over time, these animals have been able to develop various ways to withstand the winter months during hibernation through their central nervous system, and their ability to turn down their cold sensors could be one of them. For more information on the author and study, follow the link posted below.
https://news.nationalgeographic.com/2017/12/animals-hibernation-winter-cold-squirrels/
Photos Courtesy of Nat Geo
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