THE SOCIAL INSECTS 



contain enough food-reserves to rear the first brood. Prob- 

 ably the Ponerine ants, in which the queen is still relatively 

 small and forages for food before the first workers emerge, 

 retain a more primitive condition. 



One may suppose that the cloistered cell of the majority 

 of the queen ants has turned out in the long run to be less 

 risky. It does, however, put a considerable strain on the 

 colony, since it has to produce large numbers of big queens. 

 Accordingly several modifications of the usual method are 

 known. In some the size of the queen is reduced, and this 

 entails a change in the method of founding colonies. Some- 

 times the new queen is received back into her own or a nearby 

 colony. With many small queens the egg-laying rate can 

 be even higher than when there is only one large one. More- 

 over the colony is potentially immortal : its survival does 

 not depend on the life of a single queen. 



The Brians have recently shown that the common British 

 ant, Myrmica rubra, occurs in two forms. In one the queens 

 are larger than the workers and colonies are founded by single 

 females. The other has relatively small queens which go 

 into the parent or some other nest after fertilisation. Ant 

 colonies of this second sort may multiply by " budding ", 

 either through the simple division of a very large and stragg- 

 ling colony or by a group of workers and queens seeking 

 a new site. The co-existence of several laying queens does 

 not seem to be an easy achievement for most species : 

 jealousy of other egg-layers is much more characteristic. 

 Moreover, budding is hazardous because the species cannot 

 spread so rapidly or so widely. 



The commonest way round this difficulty seems to be the 

 type of behaviour known as "temporary social parasitism ". 

 The small queen finds her way into the nest of another 

 species, and succeeds in displacing the rightful queen. The 



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