UNIFORMITIES AND COMPAEISONS AMONG COMPONENTS 365 



a warmer environment, or adds clothing ; both are behaviors that 

 result in preserving usual contents of heat in his body. The fact 

 that the man has means of compensating the heat deficit by faster 

 heat production and slower heat loss than usual, does not limit him 

 to reliance upon those means. The behaviors are "reactions that 

 minister to the preservation of the individual" (Hobbes, 1647). 

 Until that rough conclusion is reached, the reactions manifested by 

 animals are just a miscellaneous collection of sensitivities ; after it 

 has been comprehended, the reactions seem anything but random. 



' ' Speaking generally, behavior regulation of body temperature 

 in poikilotherms takes the form of a locomotory reaction. If an 

 insect is too cold, its easiest way of getting warmer is to move to 

 a warmer place" (Fraenkel and Gunn, '40). That is the kind of 

 behavior that has also been observed in the maintenance of such 

 components as total substance, glucose, carbon dioxide, water, and 

 oxygen. 



Very often it is said that the animal becomes *' restless" or 

 "uneasy" in an environment unfavorable to its continuance. This 

 statement appears to be explanatory, in the absence of further in- 

 formation as to what sense organs are activated, what tissues, what 

 communicating systems, what effector organs. Once those facts 

 are known, they too are partially explanatory. When further it is 

 found that the content of water is more constant in the animal that 

 stays in high humidity, this finding, it seems to me, explains some- 

 thing which the identification of anatomical factors does not; 

 namely, that the particular behavior practiced, out of all the beha- 

 viors made possible by those structures, results in greater con- 

 stancy of water content. To state that greater constancy accom- 

 panies one behavior and lesser another, is a correlation of the same 

 order as to state that greater constancy goes with a particular kind 

 of skin, or a particular manner and rate of excretion. 



It is then a task of the student of regulations to find how wide- 

 spread that correlation is. So far, data are insufficient to allow 

 any great generalization. Listing the studies that I happen to 

 know concerning behavior toward water, moisture, food, constitu- 

 ents of food, and heat, I gain the strong impression that most pref- 

 erences for environment promote constancy of content of those 

 components ; quite independently of my guess that animals would 

 hardly have survived if they did not frequent environments that 

 are "favorable" in those respects. 



