Fat is an important part of all living things and most body fat in animals and people is white. White fat allows people to eat more than they need when food is enough. It stores those extra calories until food becomes short. 【小题1】

Hibernation(冬眠) can help animals get through the cold winter. They feed themselves on much food in fall in preparation for a long and cold winter. Animals don’t eat when they are hibernating. 【小题2】 To spend an entire winter, these animals enter a state called torpor(不活泼), where they use the white fat more slowly than they usually do.

When in torpor, it seems that animals have been sleeping. But torpor goes much deeper than that. In fact, animals’ activities slow down in torpor. 【小题3】 An animal may take several breaths and then stop breathing for several minutes. Instead of wasting energy to keep warm, bodies in torpor can remain just above freezing. 【小题4】 Every week or two, they will wake up. They stay awake for a day or so before going back into torpor. The time is different in different species. What causes the wake-up or why it happens is unclear. However, all true hibernating animals go through this cycle.

In order to wake up during the hibernation, these animals have to warm their bodies. 【小题5】 This process burns up white fat. And not only on hibernating animals, the warming process has the same influence also on humans, Ballinger explains.