...how do animals adapt to freezing Chicago winters?
Humans seal ourselves off in conditioned homes and cars, burning a lot of fossil fuel energy to do so. But animals don't have that option. So how do they do it? I decided to revisit my grade school classes and relearn what I've forgotten. And maybe there is something we can learn for design.
Groundhogs
Groundhog Day got me think, of course, about
groundhogs. As I learned in grade school, they do in fact
hibernate from approximately October to March, but toward the end of hibernation (oh, say February 2nd or so?), they enter various stages of arousal to test the temperature and scope out new territory before entering into a semi-hibernated state like
torpor. The purpose of hibernation, of course, is to conserve calories when food is scarce, so the animal's metabolic rate slows and the body cools, respiration and heart rate are depressed. Groundhogs enter into obligate hibernation, where they are aroused by internal mechanisms and usually unable to be aroused due to external stimluli. Other animals enter into facultative hibernation, or semi-hibernation, where they are able to be aroused but the purpose is the same: conserve energy when it is scarce.