464 PRIMARY FACTORS OF ORGANIC EVOLUTION. 



ably some day found by paleontological discovery. 

 We may suppose, on the basis of discoveries already 

 made in other animals, that the primitive ants and 

 termites presented homogeneous colonies, and that 

 the varied structures which they present to-day have 

 been primarily due to the usual process of specializa- 

 tion through use-inheritance. It is necessary to sup- 

 pose that the varied functions of the different members 

 of the community have modified the structures of the 

 parts essential to their performance. It is probable 

 that the earliest ants in an early geologic period be- 

 came soldiers under the usual exigencies of their strug- 

 gle for existence, and having thus secured a place in 

 the economy of nature, certain members of the com- 

 munities underwent degenerative changes, appropriate 

 to their respective functions, of a less exacting charac- 

 acter. In a second stage of evolution the community 

 would present the character of a family of varied forms 

 all of whose members would produce any or all of the 

 types of form to be found in it, under slight diversi- 

 ties of conditions, just as now, all species produce 

 young of two sexes. The differences between the 

 members of an ant community are considerable in ap- 

 pearance, but not so great essentially as that between 

 sexes. 



Finally, in a third stage of the history, the func- 

 tions of reproduction come to be the special office of 

 a few members of the community. This may have 

 been due to starvation, or to ex:cessive labor on the 

 part of certain individuals aborting the reproductive 

 powers; but whatever may have been the cause, a 

 majority of individuals became sterile. The repro- 

 ducing members of the community, however, have 

 continued to produce all the forms of the community. 



