CREATION BY EVOLUTION 



dry deserts on the one hand and in moist, tropical jungles and 

 rain forests on the other. Many of the ants in these jungles 

 and forests, owing to the seasonal drenching of the soil, build 

 their nests in trees or inhabit the pith cavities of twigs and 

 branches. We also observe that regions of the globe like 

 Australia, which are inhabited by the most primitive mam- 

 mals and birds (duck-bills, echidnas, marsupials, emus, etc.), 

 are also inhabited by the most primitive ants (bull-dog ants 

 of the genera Prornyrmecia and Myrmec/a) , whereas coun- 

 tries like Europe and North America, which have highly spe- 

 cialized mammalian and bird faunas, are similarly inhabited 

 by highly specialized and dominant ant faunas, with which, 

 however, are intermingled a small number of primitive 

 forms, which were once widely distributed but are now rare 

 and are in process of extinction. Such a distribution can be 

 explained only on the theory of evolution and is in complete 

 agreement with all we know about the geological history and 

 morphology of other organisms. 



Conclusions from a comparative study of the habits of ants, 

 or ant behavior, which is necessarily restricted to living forms, 

 agree closely with the conclusions reached in the fields men- 

 tioned. Although all ants are social, they exhibit different 

 degrees of social organization. This diversity is shown in 

 different degrees of division of labor in the colonies as coordi- 

 nated with their size and in differences shown by their com- 

 ponent individuals. Thus among the most primitive ants 

 many of the colonies are very small and the fertile females 

 and workers are much alike in size and structure, but in the 

 most highly socialized species (Dorylinae, Formicinae, and 

 Myrmicinae) the colonies may be very large and the workers 

 may be unlike the females and may even exhibit a differen- 

 tiation of the worker into secondary castes, major and minor 

 workers (Fig. 4), or soldiers and workers proper. Along 



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