|Ducks in an icy lake|
In the winter, ducks swim in very cold water and stand around on ice. Why don't their feet freeze? Why doesn't their body heat quickly drain through their feet, slowly cooling them? How do duck feet work with the rest of the duck body to keep it alive in the cold?
The winter physiology of ducks is a marvel of biological engineering, where many sophisticated systems come together to sustain a warm-blooded animal in a very cold environment. For the purposes of this blog post I will highlight only one aspect of duck physiology – reduced foot temperature – which is beautiful in its simplicity. First, a question:
On a winter morning, which will lose heat faster.
A) A hot cup of coffee
B) A can of cold soda
Answer: A, a hot cup of coffee will lose its heat faster than a cold can of soda. *if your dying to know why, click here. It makes sense, then, from an energy conservation perspective for a duck to maintain a lower body temperature in winter. The obvious hiccup with temperature reduction is that bodies need to stay warm enough to carry out their biological processes (which are temperature dependent); simply reducing body temperature could result in a loss of the body's function. The duck does a wonderful job of keeping its body functioning while reducing its temperature. It does this by breaking its body into different heating zones.
|A temperature diagram of a common gull. Like the mallard duck, this gull sustains a high temperature in its core, but – to conserve energy – allows its legs and feet to cool dramatically.|
In surfing the web I found a neat house in Vermont that is similiar to the Armstrong House. They too understand the benefit of zoning their house and heating based on use (see below).
|The three heating zones of 'Perfect House', an energy effecient house in Vermont.|
I love my warm and cozy house, so I am certainly not advocating for living in an icebox. I am convinced that a comfortable environment can be kept inside the home and energy can be conserved by strategically managing the temperature of various zones. If the mallard duck can stay active in a half frozen pond, we can surely figure out better ways to thermoregulate our houses to conserve energy.