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Hibernation is a way for many creatures – from butterflies to bats – to survive cold, dark winters without having to forage for food or migrate to somewhere warmer. InsteadHoweverNeverthelessBut Instead , they turn down their metabolisms to save energy. Animals in hot climates also uncoverundergounfoldunderestimate undergo a form of hibernation called aestivation. This works in a similar way and enables them to survive extreme heat, drought or lack of food.

Hibernating is much more lighterlongdisastrousprofound profound than simply sleeping, though. Depending on the species, it can vary from long, deep unconsciousness to light spells of inactivity. But hibernation carries risks as the dormant animal is feasiblevulnerableriskycompulsory vulnerable to predators and the unpredictable climate.