CREATION BY EVOLUTION 



of experience and tradition that is cumulative from genera- 

 tion to generation. At each of these levels some types of 

 living beings have specialized and remain fixed to this day 

 in their one-sided efficiency, or else they have been extin- 

 guished by more progressive types ; others have remained gen- 

 eralized, and some of these have given birth to the progressive 

 types which constitute the next upward step. 



After this brief survey, it remains to ask whether the 

 balanced advance we have been discussing can properly be 

 called progress, in the usual sense of that term, or whether 

 we have not been misleading ourselves by using a term which 

 implies real improvement in what to us is valuable, when 

 we should have really called it mere directive change. 



When we come to consider the main steps in biological 

 advance that are enumerated above, we find that it is possible 

 to sum them up under a few heads. There has been on 

 the whole a considerable increase in size; there has been 

 improvement in the organs adapted to carrying out each 

 type of function taken separately — organs of digestion, 

 of locomotion, of protection, of support, of sense-percep- 

 tion, of reproduction; there has been improvement in 

 the relation between these organs — that is, in the way in 

 which the different parts of the body and their functions are 

 correlated and coordinated; there has been improvement in 

 the control exercised by the brain over the body as a whole, 

 and in the quality and extent of the information received 

 about the outside world by which this control is achieved; 

 there has been improvement in the self-regulating capacity 

 of the body, as is witnessed by constant temperature or con- 

 stant chemical composition of blood in higher forms; there 

 has been a decreasing reproductive waste, an increasing 

 care for young; there has been an increase in mutual aid 

 between individuals; there has been an increase of emotional 



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