146 ANIMAL LIFE AND SOCIAL GROWTH 



which are caused by the animals reacting to a defi- 

 nite social instinct; no social instinct, no society, 

 would be his statement. Wheeler, of Harvard, 

 in his earlier writings regards insect societies as 

 the result of the extension of the time of affiliation 

 of two or more generations ; more recently he has 

 defined societies as constituting more closely inte- 

 grated and permanent systems than are mere asso- 

 ciations and primarily dependent on the reactions 

 of individuals to each other. Some students of 

 social life are inclined to regard true societies as 

 limited to those communities that show division- 

 of-labor. I, myself, have been led by reviewing 

 such facts as have been presented in this volume 

 to the view that one of the first steps toward the 

 development of definite social life is taken when 

 groups of animals acquire definite toleration for 

 the presence of other animals in a restricted 

 space. 



It appears that there are many different levels 

 of social organization, any one of which can be 

 taken as the beginning of true social life and 

 anything less advanced in the social scale would 

 then be regarded as being sub-social. If any 

 of these different criteria is examined closely, it 

 will be found that there are recognizable prelim- 

 inary steps with more poorly developed social 

 organization which appear to furnish evidence 



