AND PERSONALITY 



The influence of cold for forty million years on the whale 

 explains the larger brain, heart, thyroid gland, and blood 

 volume in the animals of the arctic as contrasted with the 

 animals of the tropics. It also explains the larger brain, the 

 larger volume of blood, the larger chest, and the higher 

 metabolism of the Eskimo and Chippewyan Indians of the 

 far north as compared with the man of the tropics and the 

 north temperate zone. 



Through the collaboration of Dr. Melling, of Chester- 

 field Inlet, Keewatin Territory, metabolism studies were 

 made at sea level, 63.45 noi "th latitude, on 63 Eskimos, 

 giving an average reading of +22.7 per cent. At Churchill, 

 Manitoba, 58.44 north latitude, metabolism studies were 

 made on 13 Chippewyan Indians, giving an average reading 

 of +18.2 per cent. Through the collaboration of Dr. P. 

 Jorda Kahle and Dr. H. Reichard Kahle, Dr. Quiring made 

 metabolism studies in New Orleans and around the Missis- 

 sippi Delta, 30 north latitude, on thirty Negroes, giving 

 an average reading of 14.6 per cent. 



In keeping with the high metabolic rate of the Eskimo are 

 his lively personality, flushed, warm skin, and free per- 

 spiration. Palpation of the brachial and the radial arteries 

 of a number of Eskimos indicated a low blood pressure and 

 a large blood volume. 



This is in harmony with our concept that the brain 

 executes energy and that the thyroid gland, which governs 

 the rate of oxidation in the brain, varies in size as an adapta- 

 tion to cold and to the needs of constant energy. 



In our wide range of studies of man and animals we have 

 seen in the comparisons of their adaptation to the heat of 

 the tropics and the cold of the north that heatstroke 

 in the hot tropics and freezing in the cold north have been 

 determining factors in the size of the brain, the thyroid 

 gland, and the blood volume. This, however, does not take 

 into account that part of the brain which we designate the 

 "mind," or "thinking brain," and the manipulative hand. 



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