Iowa is Home to Three Animals That Survive Being Frozen Alive

Remember the 1992 cult classic Encino Man? Pauly Shore, Brendan Fraser, and Sean Astin discover a frozen caveman in their backyard, thaw him out, and hilarity ensues as he tries to navigate modern life. While finding a frozen human may be a far-fetched Hollywood fantasy — or the beginning of a real-life murder mystery — nature’s got some real-life superpowered headliners right here in Iowa that can give the Encino man a run for his money.

These three incredible species survive being frozen alive, defrost when the weather warms up, and continue with life as if nothing happened. No need for 90s fashion lessons here!

Let’s take a closer look at these frosty, animal phenoms.

1. Arctic Woolly Bear Caterpillar

We see these little guys around all the time, especially in the fall. But did you know, the Arctic woolly bear caterpillar is the ultimate winter survivalist? This fuzzy creature can survive temperatures as low as -90°F by producing glycerol, a natural antifreeze that prevents its cells from freezing. As the temperature drops, the caterpillar slowly freezes from the outside in, but thanks to glycerol, its inner cells remain protected.

What's even more fascinating is their ability to go through repeated freeze-thaw cycles throughout the winter. If there's a warm spell, the caterpillar will "defrost" and become active again, only to freeze up when the cold returns. They can survive entire winters encased in ice and still emerge ready to transform into a moth. In fact, one study froze the little guy completely in an ice-cube, and it still survived! Unlike Encino Man, they don’t need to learn modern customs after thawing — they’re already pros at adapting.

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2. Wood Frog

Wood frogs take the frozen survival game to another level by essentially turning into frog-cicles. These amphibians can freeze up to 70% of their bodies, including their heart, muscles, and even their brain. During this frozen state, their body completely shuts down.

The secret to their survival lies in their liver, which pumps out glucose that acts like a sugary antifreeze. This glucose prevents ice crystals from forming in their cells, which would otherwise cause fatal damage. Once spring arrives, they thaw out from the inside out, and their heart miraculously starts beating again. They hop back to life without missing a beat, no 90s movie montages needed.

What’s particularly impressive is their ability to handle such high blood sugar levels without suffering the kind of damage that would harm humans. This has caught the attention of scientists, who hope studying wood frogs could lead to breakthroughs in diabetes treatment and organ transplantation.

3. Painted Turtle (Hatchlings)

Hatchling painted turtles face some of the harshest conditions during their first winter, as they stay in shallow nests where they are exposed to freezing temperatures. Unlike the caterpillars and frogs, they don’t use antifreeze. Instead, they rely on a process called supercooling, which prevents the formation of ice inside their bodies.

These tiny turtles reduce their metabolic rate to the bare minimum, relying on anaerobic metabolism to survive without oxygen for long periods. However, this strategy comes with risks, such as the buildup of lactic acid, which can be lethal if it becomes too concentrated.

Despite these dangers, hatchling painted turtles endure the cold without freezing solid. Their ability to avoid ice formation while buried in the icy soil is a testament to their resilience. They’re like the tough kids on the block, facing winter head-on without any fancy antifreeze tricks.

Painted Turtle Hatchlings aren't Iowa's only Turtle with superpowers — move over Teenage Mutant Ninja Turtles. Have you ever heard of brumating? It's sort of like hibernating for reptiles except it can even be done under water by some turtles Check out this video from the Iowa DNR here or below.

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That's a couple of snapping turtles doing their thing for the winter. They're not actually frozen, just brumating. These snappers, and several other reptiles, are able to continue to absorb oxygen through the skin around their necks and butts while they’re underwater for the winter. Just, think about how bad their breath smells when they wake up!

Real Life: Stranger Than Fiction

As much as I love the idea of unearthing a prehistoric buddy to teach us about the past and 'wheezing the juice', these Iowa natives are the true masters of ice. Their remarkable ability to freeze and thaw repeatedly shows us that life can indeed be stranger—and cooler—than fiction.

So, next time you're bundled up, shivering through an Iowa winter, think of these three species doing their own version of Encino Man. Unlike Brendan Fraser’s caveman, they don’t need to adjust to a modern world—they’re already experts in surviving one of the most extreme challenges nature can throw at them. Who knew the frozen stars of Iowa's backyard could outshine a Hollywood blockbuster?