Wood Frogs Freeze and Thaw Every Winter

Have you heard of the Wood Frog and its mysterious survival tactic? This frog freezes solid every winter, just to make it to spring!

Most frogs spend winter in the bottom of large bodies of water. Wood Frogs, however, sit beneath the snow under a layer of leaves. When winter rolls around, their hearts stop, blood stops pumping through their veins, and their brains stop functioning. The lenses of their eyes freeze and turn white while ice crystals surround their internal organs. The frog is technically dead, but its individual cells live on. Seven to eight months later, the frogs begin to thaw and their organs start to function again.

These frogs live for four to six years in Alaska and Canada. In the summer, these climates have sunlight for 24 hours and the temperature can rise into the 90s. When winter comes, it becomes a lot colder and sometimes even drops to -50 degrees Fahrenheit. The lowest the temperature has ever gotten in Alaska is -80 degrees Fahrenheit. Researchers are almost positive that there were Wood Frogs hibernating near the area at the time of this big freeze.

Researchers are puzzled by this mystery. How exactly do Wood Frogs survive the long winters? Hoping to find an answer, the researchers took footage of the Wood Frog thawing. Specifically, they tracked them with radio transmitters the size of a nickel and took many photos. With the data they’ve collected from this study, researchers hope to learn how the Wood Frogs survive.

This information also could be valuable beyond the frogs; if researchers figure out how Wood Frogs’ organs still function after being frozen for so long, then maybe they can find a way to store transplants longer. Researchers continue to work toward a concise answer.

[Sources: NPS.gov ; Latimes.com ]

This is really interesting, Jessica! I hope the researches make a lot of progress on studying the Wood Frog's technique. Keep up the good work! – Leila , West High School (2016-10-15 11:08)