THE ANTS OR PISMIRES 



HOW COLONIES ARE FOUNDED 



The normal method of founding new ant-colonies is by 

 a single queen after her marriage flight. These marriage 

 flights often take place over wide areas simultaneously. One 

 day during July 195 1 the common black ant, Lasius niger, 

 was swarming over much of the country between Ascot and 

 Ealing, near London, a strip about 20 miles long. Such 

 observations are not at all uncommon, and millions of queens 

 and males are involved. It must lead to more crossing between 

 different nests than would occur if each one swarmed on a 

 different day. It is not known what conditions determine 

 the time of swarming, though it is often during warm, 

 thundery weather. Just before swarming the workers are 

 seen crowded round the exit-holes of the nest, and appear 

 to be restraining the young sexual forms from coming out 

 too soon. 



Usually the queen is very much larger than the male or 

 worker. After mating, she falls to the ground, breaks off 

 her wings at a line of weakness near their bases, and hunts 

 for a crevice or digs a small cell under a stone. Here she 

 lives without food for nearly a year, being sustained by food 

 reserves derived from the breakdown of her wing-muscles. 

 Only in the Australian bulldog ants and in some of the other 

 Ponerines is she known to go out and forage for food during 

 this period. When she starts egg-laying some of the eggs are 

 eaten, so that however many she lays few survive. The small 

 number of grubs which she raises are fed on her saliva, or on 

 fragments of eggs or of other grubs. Eventually a brood of 

 unusually small workers is produced, and from then onwards 

 the queen can spend all her energies on egg-laying. This 

 method of colony-foundation is possible only when the queen 

 is much larger than the workers; otherwise she would not 



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