Cold comfort.

Do you like to be cold? Bet you don't like it as much as a polar bear. Or an arctic musk ox. Or a hummingbird.

It's true. Hummingbirds can drop their body temperatures to 55 degrees below normal at night, so they don't have to waste energy keeping warm when they can't fly around and feed.

That's just one amazing item from the book Extreme Animals: The Toughest Creatures on Earth. You'll also learn about penguins and bowhead whales and even the amazing wood frog, which doesn't hibernate when it gets cold--it just freezes. All the way through. Like a frogsickle. In the spring it thaws out and hops away. No big deal.

You'll also learn about animals that live in extremely hot or dry environments. Camels, for instance, or thermophile bacteria, which don't mind at all if you boil them in bubbling, hot mud.

Finally, you'll learn that humans are about the wimpiest animal on earth. We don't have the tools to keep us warm, or cool, or dry, or wet. Compared to the other animals, we're pretty feeble--except for one thing that beats all the others: our brain, which we use to figure out how to stay alive.

Without all these warm layers, you'd be dead in minutes! With them, you might just last a few days

Keeping Out the Freeze

Let's start at the top--the top of our world: the Arctic region, where the North Pole is.

Up there, it's so cold in winter that the entire Arctic Ocean freezes over with ice that is yards thick. The inside of a freezer is around 0 [degrees]F, but the Arctic can be much colder: down to -75 [degrees]F. A bracing -20[degrees]F is about normal for an Arctic winter's day: at that temperature your bare flesh would freeze solid in sixty seconds.

To have any chance at all of survival, you'd need to wear:

Extreme Animals: The Toughest Creatures on Earth by Nicola Davies Candlewick Press, Cambridge, Massachusetts