QUESTION OF PHYSICAL DEGENERATION 273 



rivals to get possession of the neutral markets. Modern life, 

 generally, in fact, is very largely conflict, under humane con- 

 ditions it is true, but still conflict. Hence, I believe, the sur- 

 vival of physical courage. It is true that a man in a civilised 

 state may thrive without much of it. But as a general rule the 

 combative spirit rests on a certain basis of physical courage, is, 

 in fact, correlated with it. In the same way we may hold that 

 vigour has become correlated during the evolution of the race 

 with a certain stature. The vigour is still in demand, while a 

 smaller stature is all that is indispensable. And the vigour may 

 protect its correlated yoke-fellow from diminution. 



We must now see whether any evidence of the rate of 

 deterioration of the comparatively unprotected characters such 

 as eyes or teeth is obtainable. 



In discussing pammixis 1 I showed that retrogression may be Where the 

 much more rapid than progressive evolution. An organ that ^"^ion 

 has taken many hundreds of years to build up, e.g. the horns tolerated 

 of cattle, may suddenly and totally disappear or leave behind a ^^4. 

 mere vestige. When the hornless breeds of cattle were being tion will 

 formed, selection, so far from protecting, made war upon the 

 disappearing organ. We cannot in the human frame find any 

 structure which is completely "unprotected." Even the tendency 

 to baldness, if it makes its appearance before a certain age, may 

 be checked by sexual selection. 2 Nevertheless the incidence 

 of Natural Selection upon some characteristics has been weakened 

 sufficiently to set up a state of instability. There is a great 

 range of variation, notably in the case of sight. There are 

 persons who, through congenital defect, have to hold a book 

 within two inches of their eyes : there are others who could 

 read the print of the same book at any distance between six 

 inches and four feet. Teeth in the same way vary between 

 complete soundness and almost complete unsoundness. Where 

 the survival limit is so very lo f w, lue may expect a general deterioration 

 and a rapid one. It is possible that the deterioration will not be 



1 See p. 94. 



2 The author of Degeneracy in the Contemporary Science Series has given as evidence 

 a great many facts which have no bearing on the question. Monstrous forms which 

 are certain to leave no progeny, are in this connection not worth mentioning. 



S 



