208 DARWINISM AND THE PROBLEMS OF LIFE 



support these heavy antlers on their heads if they had 

 skulls of proportionate thickness and necks strong 

 enough to sustain the ponderous head. Even the 

 animals' shoulders and other parts of the body must 

 have been powerfully developed. We see, then, that 

 strong antlers involved a whole series of co-adaptations ; 

 that is to say, it was not enough for variations with 

 larger antlers to appear among the stags, but in these 

 very cases there would have to be also a number of 

 other organs modified in a definite direction. But this 

 could not be expected in variations. They depend on 

 chance ; each varies on its own account, and there is 

 no hand guiding them from some higher standpoint. 

 If one amongst a litter of stags has larger antlers, it is 

 possible that it may also chance to have a stronger 

 collar, but some of the other parts will certainly be 

 found to be weaker ; it is too much to expect from 

 chance that so many organs should vary in the same 

 direction. The reader will be able to follow the 

 argument best by imagining a game with twenty dice. 

 The different numbers that come out on top will 

 represent the variations arising at each throw — 

 corresponding to each litter of young. As it is 

 demanded in the case of the stag that some animals 

 shall appear with, let us say, ten definite variations, we 

 must require that ten of our dice will throw the number 

 six. Certainly one of the dice, possibly two, will throw 

 a six after several attempts, but it is improbable in the 

 highest degree that ten dice will give that number, 

 however often they may be thrown. 



The Lamarckian principle meets the difficulty. 



