THE NATURAL HISTORY OF MAN 25 



Darwin's method, breeders have altered many 

 species of plants and animals almost at will ; but 

 they deny that Nature, like the breeder, exercises 

 selection. Nature, they say, is blind, and works at 

 haphazard ; she does not exercise any real selection. 

 There is in fact, they say, no such thing as Natural 

 Selection ; only a conscious agent like Man or the 

 Deity can exercise selection. Objectors of this 

 school, who are not often men of science, forgetting 

 the changes the different races of mankind have under- 

 gone, usually deny the existence of all evolution in 

 the natural world. According to them, evolution 

 is limited to changes consciously caused by man. 



As a fact, it is most difficult to prove that 

 selection does occur among wild plants and animals. 

 We have not a sufficiently intimate knowledge of 

 their lives. We cannot, in accurate statistics, tabu- 

 late their death-rates. We cannot declare, with 

 certainty, that this or that type of individual 

 survives as a rule, and that this or that type, as 

 a rule, perishes. We cannot, from intimate know- 

 ledge, declare that the possession of this or 

 that character in excelsis conduces to survival, 

 and this or that other character to elimination. 

 Our commonest wild plant is the grass. No 

 one has tabulated the death-rate of grass plants, 

 or can pretend to do more than guess at the 

 principal causes of their elimination. Our com- 



