Why Do Penguins Sleep Standing Up?

Here's a little puzzler the daughter of a friend of mine came up with the other day; do penguins sleep on their backs or their bellies. I did a little research into the topic and learned something startling. While some smaller penguins sleep in burrows and larger ones sometimes on their bellies, usually Emperor penguins sleep standing up. Turns out there's a good reason for it.

In survival school, boot camp or while having a beer with grizzled outdoorsman, you will inevitably get the "blankets of death" speech it goes something like this. "If you get out there and lay down on the ground with your blanket over you, you'll freeze to death before the Grizzly's can get you." Very melodramatic but an important point. The rule of thumb in the outdoor set is that if you have four blankets, you put three of them under you and only one over. The question is one of density.

They air, while cold, only draws heat off our body a pretty predictable rate because of its density. It only puts so many of its molecule in touch with our flesh in any given period of time so your heat only moves into the air at the rate you contact those molecules. The Earth on the other hand is much more dense. In the same amount of time it puts many more molecules in touch with us so it steals much more warmth. Try this experiment; Open the freeze and put your hand in. Cool right. Now put your hand on that leg of lamb. Much colder right? Wrong. While they may not be exactly the same temperature because of chemical difference, living in the same freezer for any period of time will bring the air and the meat to a very similar temp.. The difference you feel is in rate of exchange.

So, you're in the woods. It's ten degrees out. Both the air and the ground are about the same so you put most of your blankets against the ground and only a few against the air.

Back to penguins. Emperor penguins sit out the Antarctic winter night on the rocks and ice huddled together. While the air is deadly cold their real enemy is the equally cold but much denser rock under their feet. If they lay down, much of their body is put in contact with the ground and their insulating feathers are compressed losing their heat trapping abilities. If the sleep standing up, on the other hand, only their well insulated and padded feet feel the denser chill and they survive the incredible cold.

Myself, I'd move to Florida but, if you're going to winter in Antarctica, best sleep standing up.

References:

http://www.gdargaud.net/Antarc tica/PenguinFAQ.html

www.wikihow.com

Learn more about this author, Joel Stottlemire.
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