THE SOCIAL INSECTS 



gradually perfected their organisation. Some members of the 

 earlier types of social species, such as the Ponerines, still 

 exist, and the most highly organised types have existed long 

 enough to have evolved in widely different directions. But 

 it does seem also that many species of ant are less rigidly 

 specialised in their behaviour than any wasp or bee. Many 

 of them are able to use a variety of foods, and their apparently 

 simple nests are really more adaptable to a varying environ- 

 ment. In this way the ants have become one of the dominant 

 groups of insects in all the warmer parts of the world. 



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