Why Do Wood Frogs Freeze in Winter and Thaw?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why do wood frogs freeze in winter and thaw?

The Big Idea

Wood frogs freeze in winter and thaw because they have a natural antifreeze! They are found across Canada. It is one of the coolest tricks in the animal world.

Add Sugar

Step one: make antifreeze. As winter comes, the wood frog's blood and cells fill with sugar and a substance called urea. These act like antifreeze to protect the cells.

Freeze Safely

Step two: freeze safely. Ice forms between the cells, but not inside them. The heart stops and the frog stops breathing for a while, so it looks like a little frog-shaped ice cube.

Thaw and Hop

Step three: thaw out. When spring comes, the frog thaws. Its heart starts beating again, and it hops away, ready to find a pond and a mate.

A Closer Look

Let's take a closer look! Sugar fills the frog's cells. Ice forms only in the spaces between them. The heart and breathing pause until spring. Then the frog thaws and hops off.

Quick Facts

Quick facts! Wood frogs are one of the few animals that survive freezing. They spend winter under leaves on the forest floor, where a blanket of snow adds warmth. Many wood frogs wake up in early spring, when the pools melt. If you see a frog, look gently and leave it alone.

Think Like a Scientist

Now, think like a scientist! With a grown-up, fill one ice-cube tray with plain water and another with sugar water. Put both in the freezer. Check which one freezes first. Does sugar change the freezing? How is that like a wood frog's antifreeze?

Outro

Wood frogs are frozen in winter and hop back in spring. Science is amazing! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!