202 PROBLEMS OF HUMAN EVOLUTION 



individual may imagine to be his interest clashes with the in- 

 terest of the tribe or nation, then morality and religion intervene 

 to put down the irregular tendency which the slackening of 

 Natural Selection would allow to follow its course, to follow its 

 course for a time, that is. Natural Selection can never be got 

 rid of, though it may be put at a distance. Deviations from 

 right conduct bring ruin in very many cases to the aberrant 

 individual ; he loses health or, the society in which his lot is cast 

 being utterly uncongenial, he is somehow eliminated. In any 

 case a tribe or nation whose members are deficient in the virtues 

 that are required for social life is likely to disappear, suffering 

 defeat at the hands of its enemies. 



Man by Though man cannot get rid of Natural Selection yet he has a 

 ' hi J el? P ower infinitely beyond that possessed by any other species of 

 vironment modifying his environment, and so determining the course of 

 d t1iTcourse ev l ut i n - E yen birds make a sheltered environment for their 

 of evolu- young, and when they are about to go out into the world show 

 tion them the path of life they are to follow. The Razorbill (Alca 

 torda) coaxes her child to plunge from the cliff into the sea far 

 below, and when he has made the plunge, teaches him how to dive 

 after fish. The duck takes her ducklings to the water and in- 

 structs them in the art of foraging. Thus the young of each 

 generation have their environment and mode of life chosen for 

 them by their parents or in some cases by the community to 

 which they belong. And they have to prove themselves 

 adapted to conditions that are not of their own choosing. 

 Human civilisation is an environment which preceding genera- 

 tions have created, and which each generation in its turn, at least 

 among progressive peoples, still further elaborates. Persons to 

 whom such an environment is unsuited are likely to be eliminated : 

 there are many ways in which this comes about. And thus, 

 though there is no inheritance of acquired characteristics, yet a 

 nation can, to a considerable extent, guide the future course of 

 its evolution. Each generation in its turn has power to modify 

 the conditions of life. This is notably the case in the field of 

 morality, using the term in its broadest sense. Each generation 

 can improve the moral atmosphere in which the nation lives. 



