MILAN 



Adipose tissue. Govino (1960, 1961) and Eisner (1960) report 

 that the body fat content of all Eskimos is characteristically low. 



Eskimo summary. Possibly owing to dietary factors (Rodahl, 

 1952), Eskimos have a 20% to 30% higher basal metabolism than 

 Caucasians when S. A. (Brown et al., 1953; MacHattie et al., 1960) 

 or lean body mass (Govino, 1960) is used as a reference standard; 

 and this difference is maintained during shivering (Adams et al., 

 1958) and exercise (Rodahl et al., 1957). At high ambient tempera- 

 tures or during a hard walk in the cold, sweating accounts for most 

 of the dissipation of the excess heat (Rodahl et al., 1957). In addi- 

 tion, a higher minute volume results in a greater respiratory heat 

 loss (Rodahl et al., 1957). During a whole body cold stress, the 

 "critical temperature," which causes a rise in metabolism by 

 shivering, is the same in Eskimos and Caucasians (Adams et al., 

 1958). When either legs or hands are cooled in water, blood flow 

 is greater in the hands and forearms of Eskimos (Brown et al., 

 1952; Brown et al., 1953; Page et al., 1953; Meehan, 1955). The 

 threshold for "heat" pain is the same (Meehan, 1954) but there are 

 suggestions of a difference for "cold" pain. Tissue conductance in 

 cold water immersions is greater because of a significantly smaller 

 percentage of body fat and a higher heat production (Govino, 1960, 

 1961; Eisner, 1960). The Eskimo has a higher metabolic heat pro- 

 duction which requires a greater potency of heatdissipation mechan- 

 isms. According to Hardy (1961) it is body temperature which is 

 regulated by the hypothalamus, not the energy flux through the 

 organism. 



Athapascan Indians 



The antiquity of the northern Athapascan tribes is presently 

 unknown. The exigencies of a nomadic existence in a subarctic 

 environment imposed certain arbitrary population controls; few 

 permanent camps were established, and artifactual remains are 

 sparse. They presently inhabit interior Alaska and Canada, where 

 a continental type climate results in seasonal extremes in tempera- 

 ture. According to Sapir (1936), Newman (1954), and Kraus et al. 



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