…that frogs have a special anti-freezing technique, and can freeze and thaw and freeze and thaw and freeze…?

Photo by joshsfrogs.com

When temperatures drop, the skin freezes. Then, the water in their blood starts to become ice, and this causes the water in the frog’s cells to seep out (osmosis and what not). And at that point the liver produces massive amounts of sugar, that go into the cells (replacing the water) and prop them up so they don’t implode. The frog thus survives the winter, with shrunken (but viable) cells, ice crystals in its blood, no heart beat, no brain activity and skin so hard it feels like stone. Until Spring comes, they thaw and hop away.

I just love tree frogs (same photo ref.)