REGULATION IN BEHAVIOR 339 



the same is true if it gets into excessively cold water. If it enters an 

 injurious chemical solution, it at once changes its behavior and escapes. 

 If it lacks material for its metabolic processes, it sets in operation move- 

 ments which secure such material. If it lacks oxygen fox respiration, 

 it moves to a region where oxygen is found. If it is injured, it flees to 

 safer regions. In innumerable details it does those things that are good 

 for it. It is plain that behavior depends largely on the needs of the 

 organism, and is of such a nature as to satisfy these needs. In other 

 words, it is regulatory. 



Behavior is merely a collective name for the most obvious and most 

 easily studied of the processes of the organism, and it is clear that these 

 processes are closely connected with, and are indeed outgrowths from, 

 the more recondite internal processes. There is no reason for supposing 

 them to follow laws different from those of the other life processes, or 

 for holding that regulation in behavior is of a different character from 

 that found elsewhere. But nowhere else is it possible to perceive so 

 clearly how regulation occurs. In the behavior of the lowest organisms 

 we can see not only what the animal does, but precisely how this happens 

 to be regulatory. The method of regulation hes open before us. This 

 method is of such a character as to suggest the possibiHty of its general 

 applicability to life processes. In the present chapter we shall attempt 

 to sum up the essential points in regulation as shown in behavior, and 

 to make some suggestions as to its possible application to other fields. 



A. Factors in Regulation in the Behavior of Lower Organisms 



In the lower organisms, where we can see just how regulation occurs, 

 the process is as follows: Anything injurious to the organism causes 

 changes in its behavior. These changes subject the organism to new 

 conditions. As long as the injurious condition continues, the changes 

 of behavior continue. The first change of behavior may not be regu- 

 latory, nor the second, nor the third, nor the tenth. But if the changes 

 continue, subjecting the organism successively to all possible different 

 conditions, a condition Avill finally be reached that reHeves the organism 

 from the injurious action, provided such a condition exists. Thereupon 

 the changes in behavior cease, and the organism remains in the favor- 

 able condition. The movements of the organism when stimulated are 

 such as to subject it to various conditions, one of which is selected. 



This method of regulation is found in its purest form in unicellular 

 organisms. But, as we have seen in preceding, pages, it occurs also in 

 higher organisms, and indeed is found in a less primitive form through- 

 out the animal series, up to and including man. It is comnlonly spoken 



