MILAN 



of less body fat. It was concluded that the Bushmen had not adjusted 

 physiologically to the climate, but that they created a local climate 

 around them, using the meager available materials. 



Bushmen summary. While sleeping on the desert in his native 

 environment, the Bushman utilizes an artificial microclimate to 

 avoid cold exposure. Limited tests of skin and oral temperature 

 decline in response to cold stress revealed no difference between 

 Bushmen and controls (Wyndham et al., 1960). Bushmen subjected 

 to moderate cold stress while sleeping nude for short periods have 

 similar metabolic and thermal responses to those of controls (Ward 

 et al., 1960). 



ARTIFICIAL ACCLIMATIZATION OF MAN TO COLD 



The results of experiments undertaken to artificially acclima- 

 tize man to cola or to study the effects of chronic cold exposure 

 upon soldiers or arctic and antarctic sojourners, which complement 

 the findings of cold adaptation in chronically cold exposed natives, 

 will be briefly reviewed. Extensive and recent reviews of the litera- 

 ture on the effects of cold on man are those of Burton et al. (1955) , 

 Carlson (1954), Carlson et al. (1959) and Hardy (1960). 



Scholander et al. (1958) exposed eight inadequately clad male 

 Norwegian students to low ambient temperatures in the mountains of 

 Norway for six weeks in September and October. Metabolism and 

 skin and rectal temperatures were measured at night while the sub- 

 jects slept with 2 clo of insulation at an air temperature of 3 C. 

 Their responses to the cold stress while sleeping were contrasted 

 with thoseof 12 male controls. The acclimatized men had higher skin 

 temperatures, especially in the feet, and they were able to sleep. 

 They shivered in their sleep, whereas the controls did not sleep at 

 all. A slight but transient elevation of basal metabolic rates and a 



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