GROUP ORGANIZATION 207 



the flock which allow observers to rank the birds in 

 the order of their social dominance. This social 

 order may be relatively hard and fast, as with hens, 

 or more loosely organized on a give-and-take basis 

 among pigeons and canaries. The factors under- 

 lying the social order in these birds are complicated 

 and include such personal traits as age, pugnacity, 

 sex in general and the reproductive cycle in par- 

 ticular, as well as such environmental factors as size 

 of available space and the possibilities of establish- 

 ing special territories. High position in the social 

 order does not necessarily coincide with group lead- 

 ership, although at times it does. The survival value 

 of high position in the social hierarchy has not been 

 demonstrated, but there are many reasons for sus- 

 pecting that it may be felt in times of famine or 

 during other periods of environmental stress. 



The problems related to leadership, although 

 mentioned, were not discussed exhaustively. Em- 

 phasis was laid on the importance to the leader of 

 his followers, and on the existence of a pseudo- 

 leadership in which the animal in front is taking 

 direction from his apparent followers. 



With the Dionne quintuplets it was demonstrated 

 that social differences exist even with children that 

 have identical heredity, and a theory of environ- 

 mental differences was favored as an explanation. 



