236 GRAND STRATEGY OF EVOLUTION 



When we survey the evolutionary process as a 

 whole, we see all along this great genetic line the ex- 

 pression of these demands; and we see their ultimate 

 fulfilment expressed in: (i) a consistent increase in 

 bodily volume; (2) in centralized organic power, and 

 (3) in a self-constructive adjustability to the more va- 

 ried and subtle agencies of the outer world. It is not 

 difficult to recognize those cases where considerable 

 attainment has been made in some one of these three 

 respects, but without corresponding attainment in one, 

 or both, of the other two. 



Measured by these three standards, no other animal 

 can compare with man in perfection of bodily organi- 

 zation. And it is very doubtful whether the physical 

 and chemical properties of protoplasm, under the pre- 

 vailing terrestrial conditions, would to advantage per- 

 mit the further evolution of a physical body notably 

 different from what is generally regarded as the ideal 

 man. 



In the concurrent race between mere growth in 

 volume and better organization, the general tendency 

 is to produce more like metameres at one end of the 

 body, only to be progressively specialized by the di- 

 verse conditions towards the other end, where special 

 demands are made for service, and better returns are 

 given for service rendered. 



In accordance with this developmental law of sup- 

 ply and demand, the principal sense organs and the 

 main centres for nerve control grew up at the oldest 

 anterior end, rightly clustered around the main en- 

 trance to the body; and the three longitudinal systems 

 of conveyance became more firmly established in their 

 respective positions. As the body grew in volume, the 



