THE CANNIBAL IN EVOLUTION 167 



even yet wholly ignorant of the evolutionary effects of 

 acute diseases which are recovered from ; but it cannot 

 be imagined they have none. Their toxins by eventually 

 producing immunity must certainly be a factor of change 

 in a race, as they must be factors in the after life of the 

 individual. It may be said that when tuberculosis was 

 first active as a destructive and modifying agent, prob- 

 ably at the beginning of the pastoral ages when man 

 first domesticated cattle, a very powerful factor of physical 

 and cerebral change was introduced. If that is even 

 remotely possible, it cannot be believed that cannibalism 

 had not many obscure side effects, over and above that 

 of intensifying the struggle for existence. 



Organized war in itself, though it is a subject which 

 has employed so many minds, has rarely been considered 

 as a very ancient factor in evolution. We may take it for 

 granted that it did not originate in the mere love of fighting. 

 The joy of conflict is assuredly a by-product of superfluous 

 energy, and even now much rarer than is assumed in 

 romance. Yet if the temporary sullen alliance of some 

 early prehistoric men, in periods possibly late Miocene 

 in date, was the very beginning of tribal unity, and if their 

 joint efforts procured success against a common enemy 

 of both, we are entitled to call such an expedition the 

 very beginning of organized war, as distinguished from 

 solitary hunting, and the origin of immense evolutionary 

 changes. So far as I am aware, though man's intellectual 

 advance has been frequently attributed to his hunting 

 proclivities, as calling forth qualities advantageous to 

 him who was successful, and thus aiding his survival, 

 while inter-tribal warfare is no doubt recognized as a factor 

 of his progress, the reasons usually assigned for such war- 

 fare are the tolerably obvious ones still displayed among 



