russ_watters said:
Perhaps your body adjust it's reaction time? Ie, if you're used to hot weather, your body immediately starts sweating, opening capillaries, etc. when you feel the change in temperature and before it actually overheats? That's how programmable thermostats work - they actually anticipate based on past experience how long it takes to change the temperature and turn on the heat/ac before they sense the temperature is too high/low.
I wish I had a real answer to your question, but it seems the consensus is none of us really knows why this happens. That is an interesting idea though. Since different temperature climates are also at different latitudes with the associated differences in photoperiod, it would be possible to predict to some degree seasonal temperature variation. At a higher latitude, you'd have slightly shorter days in summer than at a lower latitude, so the question would then be if those daylengths are sufficiently different and sufficiently detected by humans to predict temperature changes.
I think there would have to be some predictive cue such as photoperiod telling the body that it's the time of year when reaching 65 degrees at a particular phase of the circadian rhythm predicts it's going to be a hot day and you'll need to start cooling sooner. Sort of a predictive homeostatic mechanism rather than a reactive one.
Well, wait, (bear with me here, I'm thinking this through as I'm typing)...if that was the case, then by predicting changes, your body would begin adjusting to a predicted temperature before that temperature occurred, which would mean you wouldn't be maintaining proper homeostasis with the environment. If that happened, you'd expect that someone living in a hot climate who began cooling before the temperature got that hot would have a decrease in body temperature prior to a rise back to basal level when the cooling rate was appropriate for the ambient temperature. If that were the case, you would predict that the timing of diurnal changes in body temperature might be similar among groups of people at different latitudes, but the average temperatures at each time would differ between groups of people at different latitudes, or would correlate to latitude.
Now, where are those kids in need of science fair projects when you have an idea to give to them? This would be a fun science fair project that could be done online by getting volunteers to take their temperature a few times of day (morning, noon, evening, for example) for a few days and report in with their latitude, ambient temperature at the time they take their body temperature and see if there's a correlation.
Of course, the differences might turn out to be too subtle to detect with the accuracy of your typical drug store thermometer. But, we'd be finding out if we react to or predict temperature changes. Oh, we'd have to get everyone to eat at the same time too, otherwise body temperature changes associated with mealtimes would screw up the results.
We can make this our first PF bio lab experiment.
