SOCIAL AND COMMUNAL LIFE 41 1 



animals are said to be gregarious in habit, and this gre- 

 gariousness is undoubtedly advantageous to the individuals 

 of the band. The great herds of reindeer in the North, 

 and of the bison or buffalo which once ranged over the 

 Western American plains are examples of a gregarious- 

 ness in which mutual protection from enemies, like wolves, 

 seems to be the principal advantage gained. The bands 

 of wolves which hunted the buffalo show the advantage 

 of mutual help in aggression as well as in protection. 

 Prairie-dogs live in great villages or communities which 

 spread over many acres. By shrill cries they tell each 

 other of the approach of enemies, and they seem to visit 

 each other and to enjoy each other's society a great deal, 

 although that they are thus afforded much actual active 

 help is not apparent. The beavers furnish a well-known 

 and very interesting example of mutual help ; they exhibit 

 a communal life although a simple one. They live in 

 villages or communities, all helping to build the dam 

 across the stream which is necessary to form the marsh 

 or pool in which the nests or houses are built. 



Communal life. TECHNICAL NOTE. See technical notes, 

 pp. 212 et seq, for directions for work in connection with the study 

 of the communal life of ants, bees, and wasps. 



When many individuals of a species live together in a 

 community in which the different kinds of work are divided 

 more or less distinctly among the different members and 

 where each individual works primarily for the whole and 

 not for himself; where there is, in other words, a thorough 

 mutual help and mutual dependence among the members 

 of the community accompanied by a division of labor, the 

 life of the species is truly communal. Those animals 

 which show the most elaborate and specialized communal 

 life are the termites or white ants, the social bees and 

 wasps, and the true ants. Of these the ants and honey- 



