INTELLIGENCE, POWER, 



What were the circumstances under which man departed 

 so completely from the other primates in the relative size 

 of the thyroid and adrenal glands? The gorilla, the chim- 

 panzee, the baboon, and the monkeys have adrenal glands 

 two or three times larger than the thyroid gland, for all of 

 these tree-dwelling anthropoids have need for outburst 

 energy to escape the leopard and other enemies in their 

 active tree existence. Although the long arms and long legs 

 of man, his final upright posture, and his manipulative hand 

 evolved during his tree life, the brain and the thyroid 

 gland of man could not have been evolved during that 

 period. Walking, thinking man in the tree would be an 

 energy misfit. Nor did the tree life equip man to escape his 

 enemies by running. Man's adaptation was the evolution of 

 the organ of strategy, namely, a thinking brain. The early 

 ancestors of man underwent their gradual evolution from a 

 life in the trees to a life on the ground, with a slow assump- 

 tion of an upright posture, as exemplified by the gorilla 

 today. 



Thus we may suppose that dawn man came down from 

 the trees in the tropics, followed his animal food to the 

 grasslands, and became a hunter and a nomad. In conse- 

 quence, gradually the adrenal glands, through natural 

 selection, devoluted, and the thyroid gland evoluted, finally 

 reaching the formula of modern man, whose thyroid gland 

 is two and a half times the size of the adrenal glands. 



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