Fur coats and thick layers of blubber might be the adaptational standards for icy climates. But when it comes to braving the frosty air, the humble wood frog is simply too cool to be bothered. The unassuming little amphibian can be found from the Appalachian mountains all the way to Alaska, and depending on the season, you might find it swimming about, eating flies, or literally frozen solid.

Image credit: Brian Gratwicke via Flickr (CC BY 2.0)

Wood frogs have a special adaptation that allows them to load their cells with glucose. This lowers the freezing point of their tissues, acting a bit like antifreeze. In sub-zero temperatures, they are thus able to survive the winter suspended Hans-Solo-style in solid ice. Come spring, they simply thaw out and hop away.