American wood frog

For most animals, freezing means certain death, but for North American wood frog, freezing is actually a strategy to survive the long winter. When the temperature decreases, the organ of the frog is surrounded with cold water, which causes the heart stops beating, the lungs to stop breathing and the kidneys stop working. Frogs enter a state of "suspended animation" where it can live for months until the spring came at the time it will melt and become fully functional again in 10 hours.