The Wood Frog

I just finished reading a fascinating and well written article1 about the wood frog2 which is a species of frog that can survive far northern winters by allowing itself to be frozen, rather than seeking hibernation in ponds that do not completely freeze:

What does a hibernating wood frog look like? There is no muscle movement. No heartbeat. No breathing. For the entire winter, the wood frog is like a lump of hard, frigid, icy stone carved in the shape of a frog. But it’s alive, in a state of suspended animation.

It does this by flooding its cells with glucose, but allowing the intercell tissue to freeze:

So on the one hand, the wood frog’s body allows ice to form around the outsides of cells and organs; and on the other hand, it prevents ice from forming inside the cells--thus avoiding the lethal damage suffered by most animals when they freeze.

So basically biology is a miracle and if anyone tries to argue otherwise we can just mention the insane adaptation of the wood frog.


  1. https://www.nps.gov/gaar/learn/nature/wood-frog-page-2.htm 

  2. https://www.nwf.org/Educational-Resources/Wildlife-Guide/Amphibians/Wood-Frog