28 ORGANIC EVOLUTION 



through education, since it is immediate, no period of dis- 

 advantage appearing in the early life of the individual. The 

 death-rate of the individuals which become adapted through 

 education may be greater than that among the individuals 

 with more perfect innate adaptation. Thus in time innate 

 adaptation may be established for the species as a whole. 



Mankind are in all intellectual features more plastic than 

 animals of any other species. By education, to which they 

 readily respond, they learn to so adapt themselves to un- 

 favorable conditions as to escape from much of the stress 

 of the struggle for existence. They have learned to protect 

 themselves from cold and inclement weather, from hunger 

 and from disease, and from many other dangerous elements 

 in their environment. Man's great individual adaptability 

 has secured his survival, but at the same time, has greatly 

 hindered his evolution. This will be discussed later. It is 

 desirable here merely to observe that plasticity (educability) 

 in any species of organism hinders its evolution by lessening 

 the destruction which lack of conformity to the environment 

 would cause. If the plasticity is very marked, as among 

 human kind, it may almost prevent evolution through natu- 

 ral selection. (Cf. Appendix I.) 



Artificial selection. 



Before leaving the subject of natural selection it would 

 be well to refer to the similar phenomena of artificial selec- 

 tion. Florists and breeders of animals use methods that 

 very closely parallel natural selection. We are familiar with 

 the remarkable results which have been obtained in the 

 rearing of domestic animals and plants. The many kinds 

 of horses in use (Plate 4) are widely different from the origi- 



