INTELLIGENCE, POWER, 



heart, a larger thyroid gland, and a greater volume of blood 

 than a mammal of corresponding size on the land. It is 

 the abstraction of heat by water that enables the porpoise 

 to use such a high degree of constant energy without 

 heatstroke. 



In the dissection of the porpoise it was at once evident 

 that the muscles were those of a mammal. In vascularity 

 and in color they were strikingly different from those of a 

 fish. The color of the muscles was even richer and darker 

 than that of the muscles of a lion or a zebra. 



The thyroid glands lay in the usual mammalian position 

 and were connected by a slender isthmus. The weight of the 

 thyroid glands was 18.29 grams. Not until we saw the 

 adrenal glands, which weighed only 10.41 grams, did we 

 fully appreciate the continuous activity necessary to main- 

 tain the high level of mammalian oxidation in a cold sea. 



Outbursts of activity would not benefit the porpoise. The 

 porpoise requires an exceedingly high level of constant 

 activity, supplemented by emergency oxidation. Therefore, 

 the porpoise needs a large brain, a large heart and blood 

 volume, a large thyroid gland, and, as in man smaller 

 adrenal glands. 



Dissecting out the brain and the pituitary gland in the 

 porpoise was almost as difficult as chiseling the brain out of 

 its bony case in the elephant. The brain of the porpoise 

 weighed 1,735 grams. It was strikingly larger than the 

 human brain and had a ratio of brain-to-body-weight of 1 185, 

 approaching the ratio of the brain-to-body-weight of man. 



The energy requirements of the porpoise are above those 

 of any land animal or bird or fish, since the land animals 

 and the birds and the fish do not have to travel to get their 

 breath. In order to secure its prey, the porpoise must 

 compete with the shark, the sailfish, the barracuda. For 

 aeons the porpoise has been under the necessity of swim- 

 ming to the surface to fill its mammalian lungs. It is as if 

 the porpoise ran uphill all its life. 



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