Responses of Bushmen and Europeans on exposure to winter night temperatures in the Kalahari

¹ Applied Physiology Laboratory, Transvaal and Orange Free State Chamber of Mines, Johannesburg, South Africa

Eight Bushmen and five Europeans were exposed during winter nights in the Kalahari desert to temperatures ranging from about 27°C to 2°C. Oxygen consumption and skin and rectal temperatures were measured over the period of 1–2 hours of exposure. Comparison of increased metabolic rate with decreasing air temperatures measured in this study is made with similar data on young Norwegians. Bushmen and Europeans respond in a similar manner metabolically to the degree of cold stress experienced. Skin temperatures of the former tend to be lower and metabolism greater than in Europeans. The lower metabolic rate of Europeans is concluded to be due to the greater insulation afforded by their considerably larger subcutaneous fat deposits. These findings on the cold response of Bushmen contrast with those on Australian aborigines in comparable environmental conditions.