First, in my other posting I stupidly called Scott Steve. Sorry 'bout that, my head was elsewhere (you define the place). There are a number of car and ferret postings that are neglecting something - there is a difference between heat and temperature. A ferret needs to gain or lose heat to maintain body temperature. One reason it is more sensitive than a dog, or even cat, is that its smaller body mass allows smaller heat changes to achieve the same temperature change. The same amount of heat change generates a larger temp. swing. Throw in the heat exchange system differences and smaller surface to radiate from and you wonder how they survived summers before A/C was invented. In Toons' case. the caah was paahked (Boston area again) in the shade, but I can assume that it was in the sun before that. It gained heat in the seats and entire interior during this time. Once the windows were opened it my have lowered the air temperature to ambient, but the rest of the car is still radiating the stored heat. Back to Toons - she had been romping and having a good time. The exertion produces body heat. Back in the car she is trying to lose it, but the surround has a higher level of heat (even if the temp. differential seems small). That damn law of thermodynamics kicks in and her smaller mass acts as a sink for the rest of the car interior despite the "cool" air temp (which begins to rise ,too, as the interchange rate with the outside drops). The biological means to overcome this gain is swamped and Toons gets warmer. The rest has been eloquently stated by Scott. The reason for this pompous discourse is to emphasize that heat is not the same thing as temperature. A seemingly small temperature difference is nothing if the difference in thermal mass is huge. That is how that "magic defroster" on TV works. When your ferret is in the car, think heat, not temperature. The same thing goes for radiant gain from the sun. That's why the car interior gets to the outrageous temps others have stated. The rate of gain exceeds the rate of loss. Rudy the ferlosopher [Posted in FML issue 1141]