A hibernating dormouse curled up asleep in its nest next to hazelnuts

Hibernation

Hibernation is an extended period of deep sleep, or torpor, that allows animals to survive winter extremes. Reducing metabolic rate and lowering body temperature enables survival through cold periods when food is scarce or has little energy value. Hibernating species usually work hard to build up large fat reserves before they bed down, and subsist on this during their torpor. They might wake up at intervals to defecate or top up on food.

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