142 THE SOCIAL LIFE OF ANIMALS 



or to chloroform. Tests that have been made by 

 others indicate that animals that are more active 

 physiologically usually succumb sooner under such 

 adverse conditions, just as these rapidly-working ants 

 were found to do. These are exceedingly interesting 

 results because here we see that ants with apparently 

 innate differences in speed of fundamental processes 

 are affected in their speed of digging by the presence 

 or the absence of a nest mate. The ant of intermediate 

 speed, presumably with an intermediate underlying 

 reaction system, is most interesting of all, because it 

 can be either speeded up or retarded according as it 

 is placed with an active or a more passive individual. 



In this connection it has been known for over a 

 decade scientifically what was common sense before 

 that time, namely, that human animals, whether 

 adults or children, can accomplish more mental and 

 physical work, at least of certain kinds, and will work 

 with greater uniformity when in association with 

 others doing similar tasks, than if obliged to work in 

 isolation. (15, 84) 



Such considerations lead directly to problems con- 

 cerning the effect of numbers present on the rate of 

 learning in man. Here we find a set of questions that 

 have great and immediate human significance. The 

 world over, the training of the young animals of 

 their own species is one of the major preoccupations 



