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NatureSurprise 5/5Difficulty 4/5Reviewed on September 13, 2026

The wood frog can freeze up to 70 percent of its body and come back to life in spring.

Why it is true

Up to 70 percent of the wood frog's body water can freeze. The heart stops beating, breathing ceases and the blood freezes. In spring, the animal thaws and resumes normal activities. The mechanism involves natural cryoprotectants such as glucose.

Source: PLOS ONE

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