AND PERSONALITY 



brain of uniquely large size, a thyroid gland of corre- 

 spondingly large size, a large heart, and a large volume of 

 blood, fat, and blubber. It would seem that the Thermos 

 bottle principle in evolution, whereby the living furnace is 

 encased in blubber, is not sufficient in the cold north and 

 that the inner furnace has to be stoked to a higher constant 

 intensity; in other words, in the cold north, in order to 

 maintain the normal warm-blooded state, the internal 

 furnace must burn more intensely. 



Allowing for the slight differences in weight, the 

 adaptation to cold alone upon the size of the brain may 

 be seen in a contrast of the weight of the brain in a harte- 

 beest collected in equatorial Africa with that of a caribou 

 collected during the summer in the arctic and in a contrast 

 of an African hare with an Arctic hare. 



In Hudson Bay at Churchill we collected eight white 

 whales. We took their temperatures immediately after 

 capture and found them to be the same as our own tem- 

 peratures. The internal temperature of the whale and the 

 porpoise is the product of all the protection that fat, oil, 

 and blubber can give to keep out the cold and keep in the 

 heat. 



On the other hand, the high rate of metabolism executed 

 by the uniquely large brain, the uniquely large thyroid 

 gland, and the uniquely large heart and blood volume of 

 the whale and the porpoise produces a rate of oxidation not 



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