FIGURE 1.

Physical models (three cubes; A, B, and C) to illustrate the influences of variations in morphology and composition on passive heat exchange, adapted with permission from Taylor and Notley (16). Each cube was first heated in a stirred water bath (40°C) to a common central (core) temperature, and then cooled (time zero) in a second water bath (20°C). Panel A shows time-dependent changes in central temperature in each object, whereas panel B shows the cooling rate of each cube over a 5°C temperature range (30°C to 25°C), as bolded in Panel A. Panel C denotes the dimensions and thermal properties of each cube. Cubes A and B (both beeswax) differed only in size, with cube B being larger than cube A. Cubes A and C differed only in composition, with cube C being made of plasticine, and thus, of higher density and thermal conductivity, but of lower specific heat capacity.