Hibernation is more than just a lengthy nap.
冬眠不仅仅是长时间的睡眠。
It's an evolutionary adaptation possessed by some animals to help them live through unfavorable conditions in their environment.
它是某些动物进化出的一种适应性特征，帮助它们挺过所处环境中的恶劣条件。
But what animals hibernate, and why do they need to?
但哪些动物会冬眠，它们又为什么要冬眠呢？
Hibernation refers to the period when an animal, mostly warm-blooded mammals, such as the jumping mouse or the woodchuck, enters a state of torpor, in which the animal's body temperature and metabolic activity are lowered as a response to adverse winter conditions.
冬眠是指动物，多为恒温哺乳动物（如跳鼠或土拨鼠），进入一种蛰伏状态，在这种状态下，由于冬季恶劣条件的影响，动物的体温和代谢活动会降低。
While hibernation is specific to dormancy during winter, estivation refers to when animals experience torpor during dry, hot summers.
冬眠特指动物在冬季的休眠，而夏眠则是指动物在干燥炎热的夏季进入蛰伏状态。
Hibernation is often triggered by changes in an animal's environment, including changes in temperature and food availability, and shorter days.
It is believed that the blood of hibernators contains a compound called Hibernation Induction Trigger, or HIT, that tells the animal it's time to hibernate.
Hibernation allows animals to live in regions where non-hibernating animals would not survive during the winter months.
Hibernating animals avoid the burden of competing with others when resources are scarce.
Not all hibernators follow the same rules.
