HUMAN RACIAL RESPONSES 



(1956) language affinities between the Apaches and the Northern 

 Athapascans indicate that the former migrated southward 400 to 

 600 years ago. 



Response to whole body cooling . Meehan (1955) measured 

 metabolic rates, and surface and rectal temperatures of nine male 

 Fort Yukon natives and Caucasian controls clad in a light under- 

 wear suit and exposed for 90 minutes to an air temperature of 

 6 G to 7 C. Initial resting metabolic rates and respiratory quo- 

 tients were close to basal values and were the same in both groups. 

 In the cold room, the natives shivered more and had a significantly 

 higher metabolic rate increase (142±22%) after 90 minutes than 

 did the Caucasian controls (77±11%). The hands and feet of the 

 natives were significantly warmer and the Caucasians incurred a 

 greater total heat debt. 



Irving et al. (1960) measured the sleeping metabolism, rectal 

 temperatures, and skin temperatures of eleven male Old Crow 

 Indians and seven Caucasian controls. These parameters were 

 measured during 7 hours of warm sleep and 7 hours at C with 

 about 1 clo insulation. Initially, the Indian basal metabolism was 

 approximately 14% higher than Benedicts' standards. By using 

 "lean weight" as a reference, the two groups did not differ in meta- 

 bolism. During the cold exposure the average elevation of meta- 

 bolism in the Indian subjects was 29% and in the Caucasians 32%. 

 During the warm nights the Indians and controls were awake 12% 

 and 13% of the time respectively. During the cold nights the 

 Indians were awake 49% and the Caucasians 69% of the time. Dur- 

 ing both warm and cold nights the Indians lost more heat from 

 body storage. However, the skin temperatures of the Indians and 

 Caucasians did not differ significantly, and no evidence was found 

 of adaptation in metabolic rate of thermal reactions. 



Eisner et al. (i960) , in order to investigate seasonal differences 

 in the Old Crow population, restudied eight male Indians in the 

 spring. Metabolism, skin temperatures, and rectal temperatures 

 were measured during sleep at C to 3 C with 1 clo insulation. 

 Basal oxygen consumption of four natives was approximately 10% 



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