These animals can freeze solid in winter. Here’s how they survive.

Antifreeze proteins. Sugar-packed cells. Brain shutdowns. To make it to spring, many species find surprising ways to stop their bodily functions.

A college professor at my university years ago shocked his class with a demonstration. He showed off a wood frog that was still alive but frozen solid. Then suddenly, he threw it against a wall and it shattered. Everyone gasped.

Moments later, he explained that he hadn’t actually thrown the frog. For dramatic effect he had switched the frog for a hunk of ice. But the goal was to illustrate a point: That a wood frog does in fact freeze as solid as ice to survive the winter. Then it thaws again in the spring.

The wood frog is one of the most frequently studied animals on Earth that freezes. When temperatures drop in the fall, it nestles in leaves and

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