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Discovery Files - "Frogcicle"

Discovery Files
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Discovery Files - "Frogcicle"

Credit: NSF/Clear Channel Communications/Karson Productions

Audio Transcript:

Frozen frogs. The ultimate in chilling out.

I'm Bob Karson with "The Discovery Files" -- new advances in science and engineering from the National Science Foundation.

The North American wood frog has an unusual way of dealing with winter. It freezes itself solid, then thaws in the spring.

University of Ohio researcher John Costanzo studies these supercool creatures. At the first sign of a freeze, the frog's body sends signals that pull water away from its center. The water freezes, encasing the organs in a block of ice. The heart and kidneys shut down, and respiration ceases. Water in the cells is kept in a liquid state by a glucose-based amphibious antifreeze. The frog stays in suspended animation for months.

In spring, the frog thaws from the inside out. First, the heart and brain, then the entire body. Within ten hours, it's living, breathing and hopping again.

Research on this phenomenon could mean a big leap in our understanding of ways to store organs for transplantation.

"The Discovery Files" covers projects funded by the government's National Science Foundation. Federally sponsored research -- brought to you, by you! Learn more at

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