Studies that reveal how hibernating ground squirrels (Spermophilus tridecemlineatus) experience extreme cold and rapid temperature changes without harm to the nervous system could help researchers understand the effects of hypothermia and provide clues to developing safe ways to freeze cells and tissues (Nature. 2000;407:317-318).
During hibernation, a ground squirrel's body temperature drops nearly to freezing, but it rewarms to normal during brief periods of wakefulness. Researchers at the National Institutes of Health found that when the hibernating squirrel's body temperature plummets, lipids and proteins in the internal cell membrane of neurons and glia rearrange themselves in ways that preserve cell function.
Stephenson J. Cold Comfort. JAMA. 2000;284(15):1915. doi:10.1001/jama.284.15.1915-JHA00010-2-1