32 Studies in Animal Behavior 



may perhaps suffice. 



From the standpoint of analysis as well as that 

 of evolution, a considerable interest attaches to the 

 behavior of the simplest forms of life. Here, if 

 anywhere, one might expect behavior to be capable 

 of analysis into physical and chemical processes. 

 The behavior of the Protozoa for this reason 

 has attracted a number of careful workers who 

 have endeavored to test how far such behavior 

 can be explained in terms of simpler factors. Jen- 

 nings in particular has done a large amount of 

 careful observational work in this field; he has 

 shown in the case of Amoeba, which is often re- 

 ferred to as an almost structureless mass of jelly, 

 that the behavior is surprisingly complex, and at 

 present incapable of being explained in terms of 

 physical and chemical laws. This does not imply 

 that the behavior of Amoeba is, in the last analysis, 

 incapable of such explanation; it simply means that 

 our present knowledge is inadequate for this task. 

 Even the simplest organism is a very complex struc- 

 ture from the standpoint of the chemist. And it is 

 not to be wondered at that the simplest creatures 

 often act in ways which we can neither predict nor 

 explain. Minute study of the behavior of the low- 

 est organisms, however, has revealed a remarkable 

 amount of uniformity. The activities of these forms 

 are stereotyped, yet plastic, and while no intelligence 

 has been proven to occur in any of them, their be- 

 havior is often capable of modifications in various 



