Wood frogs can survive freezing.
Tree frog (Rana sylvatica), inhabits in Alaska, freezing in winter to the extent that it becomes like a piece of ice. While frozen, the frog is not breathing, her heart and blood circulation stops, she can not move. However, with the onset of spring frog "thaws" and return to normal life. It is highly unlikely that such a skill might develop spontaneously by coincidence. In order to make the system function of the body of the frog again, it is necessary to use an extremely complex genetic program.
In winter, about 35-45% of the liquid in the body of the frog freezes. This extracellular ice is essentially contained under the skin and between the muscles. With this frog becomes hard as a piece of ice! Most of these frogs ledyshek survive the winter in Alaska in burrows on the ground level.
With the arrival of spring tree frog ends its truly amazing transformation. Just a few hours the frozen body of a frog alive: restores normal breathing, heartbeat, blood flow, as well as the work of the brain and all functional systems. Frog again can move, jump and mate.
Sea cucumbers can be transformed from liquid to solid and vice versa