430 V. THE NATURE OF EVOLUTION 



lity, and a sense of well-being, even euphoria, replaced depression, 

 and abnormal irritability disappeared (114). Even normal individuals 

 at times respond, the immediate effect being drowsiness and release of 

 nervous tension, if present. These effects are not due to suggestion, 

 because sheep, in a state of neurosis due to overtaxing the nervous 

 system in conditioned reflex experiments, showed marked improve- 

 ment under adrenal extract therapy (115). 



In corformity with this concept, according to Boas (86) the increase 

 in the stature of children is greatly influenced by their number in 

 the family, and the increase is the more manifest the fewer the 

 number, as shown in Fig. 39. It can be expected that nervous tenseness 

 of animality may be necessary the more and the chance of hunger 

 may be the more frequent, the larger the size of the family. 



This is most clearly demonstrated in the investigation of the 

 Department of Education of Japan into the bodily change of Japanese 

 children during and after the Second War. It is reported that the 

 stature of the children was remarkably reduced during and after the 

 War and that the reduction was distinct in the length of legs as 

 compared with the almost unchanged trunk (116). It should be 

 realized in this connection that the increase in Japanese stature in 

 Los Angeles occurs chiefly in legs not in trunk. Such a reduction of 

 stature is, of course, mainly ascribed to the want of food which 

 might not only lead to the insufficiency of ACTH and growth hor- 

 mone, but also might stimulate the production of thyrotrophic hormone. 

 However, in addition to this, irritable, uneasy life during the war 

 might play a prominent part in this reduction in stature. 



On the other hand, the removal of uneasiness will result in the 

 increase in stature, as evidenced actually by an experiment with 

 animals. Thus, according to Weininger (117), albino rats, gentled for 

 three weeks for ten min. a day following weaning, would show 

 significantly greater mean weight. The difference in weight between 

 experimental and control groups was related to a significantly greater 

 proportion of adipose tissue and to a significantly greater skeletal 

 length for the former. 



Porter (86) found that students with high scholastic standing are 

 generally above the average in height. Entirely similar phenomenon 

 was afterwards confirmed by Sargent (103), They considered that 

 the growth of bright boys was more rapid than that of dull boys, 

 but it may be more reasonable to suppose that the children able 

 to be endowed with a higher education are rather civilized and better 

 nourished, and perhaps need less nervous tenseness of animality. 

 The Provident Mutual Life Insurance Co. of Philadelphia surveyed 

 270,000 men to see if there was any relationship between height and 



