Evolution and Progress 439 



gans of parasites, or the reduced eyes of cave-dwelling animals 

 were obviously no " improvement " in the ordinary sense, 

 however adaptive they may be for the organisms in question. 

 There is no need for assuming that evolution means the 

 emergence of superior individuals from inferior ancestors. 

 This unwarranted identification of evolution with progres- 

 sive improvement has indeed furnished '' arguments " against 

 evolution. Thus one writer, " If whales and seals have de- 

 scended from four-footed land animals, that is not evolution, 

 that is deterioration." 



Such misunderstandings are the unavoidable manifesta- 

 tions of thought-patterns fixed early in life. They are as 

 likely to be found among those arguing on one side as among 

 those upholding the other. A leading paleontologist only a 

 few years ago urged the teaching of evolutionary ideas in 

 schools, " in the real sense of ascent and progress." Of course 

 the other senses are just as " real " and just as worthy of 

 consideration. 



If evolution is not synonymous with progress it is still 

 a dynamic concept. It implies constant becoming, constant 

 change. It is necessary to distinguish between the biologist's 

 conclusion from all the evidence that there is this constant 

 change which he calls organic evolution, and the human 

 mind's temptation to transform the broad concept into a 

 philosophy of life. This is a necessary distinction. Whatever 

 misuse the individual may make of his own interpretations and 

 applications of evolution will be invariably charged to the 

 biologist who upholds evolution as a generalized statement 

 regarding the known facts of life. 



From the observed facts among plants and animals, we 

 may be confident that there is evoluton, that evolution af- 

 fects the " higher " and competitively nonessential functions 

 as well as those that are vital in the struggle for existence, and 

 that man himself comes within the influence of those forces 

 that bring organic evolution about. In some cases the process 

 leads to more and more highly specialized and more and more 

 complex forms. We may, if we wish, consider this pro- 



