194 ASSOCIATION OF ORGANISMS 



prehensive term, including the union of living things of 

 the same or different species, where the results are of 

 most varied character. 



Family Groups, Herds. — The simplest example of 

 mutual aid appears in the case of famihj groups where, 

 as in the case of swans, geese, certain apes, antelopes, 

 elephants, and many other species, a keen-sensed parent 

 leads and protects the offspring of different ages. 



In the lierd a few or many family groups become 

 merged into a larger association of individuals, which may 

 number thousands. Examples are found among wild 

 sheep, deer, and several species of antelope, where a 

 female may lead, or among several other kinds of ante- 

 lopes and bison where one or more powerful males act as 

 leaders. In this case also the strong lead the weak to the 

 feeding grounds and protect them against the attacks of 

 enemies. 



Bee Colonies. — Beyond this point several series of 

 examples could be cited which illustrate an increasing 

 cooperation and division of labor, culminating in complex 

 social organizations such as those of the honey bee, ant, 

 and man. In the bumble bee for instance, we find a type 

 of communal life advanced a stage beyond that of the 

 family group or herd. In the spring a female, that has 

 passed the winter in some sheltered nook, emerges, selects 

 a site for a nest, constructs cups for a mixture of honey 

 and pollen, that she collects, and on this raises a brood 

 of from three to twenty young. These become immature 

 females or workers that henceforth care for other young, 

 enlarge the nest and leave the queen mother the sole duty 

 of producing the family. Males appear in the fall to- 

 gether with certain females, which become queens the fol- 

 lowing year, while all the others die with the coming of 

 winter. 



The honey bee community, in a general way, resembles 

 that of the bumble bee. A queen heads the colony, com- 

 prising many thousands of immature females or workers, 



