THE SOCIAL INSECTS 



The process of natural evolution can be looked on, by 

 analogy, as a slow but very prolonged process of training in 

 which the rewards are food and successful reproduction and 

 the punishments hunger and extinction. In a social mammal 

 or insect, other members of the community are an essential 

 part of the environment without which the individual is 

 almost as helpless as a fish out of water. This reaction to 

 other individuals is innate and is the only element of social 

 behaviour which is common to all such species. 



It cannot be supposed that social insects have any sense of 

 right or wrong. So far as they are obeying the laws of their 

 own physiology, they are very unlikely to have moral 

 scruples. But from the evolutionary point of view motives 

 are unimportant ; ethical conduct is what benefits the com- 

 munity, even at the expense of the individual life. The code 

 developed during evolution, because it is such a slow 

 growth, is apt to be too rigid to succeed on all occasions. 

 It leads to those " errors " of instinctive behaviour which 

 Fabre and some other naturalists have treated as contra- 

 dictions of the Darwinian theory. This, however, is a mis- 

 apprehension ; natural selection is seen just as clearly in the 

 failure as in the success of a behaviour pattern, provided that 

 in the long run the results determine survival. 



The adjustment of individual behaviour to social needs 

 is closely related to the topics already discussed. An insect 

 living in a society has to do a greater variety of tasks, at least 

 until an advanced division of labour has been evolved, than 

 does a solitary species. Its action cannot follow any very 

 rigid time-table. Perhaps the various methods used in cooling 

 the nest when it gets too hot are the most striking example 

 of sudden adjustment of behaviour to the needs of the colony. 

 If a solitary species gets too hot, it may try to escape, but it 

 has never been known to do anything to make its nest cooler. 



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