SOCIAL HEREDITY 279 



number of wild species of British birds and mammals. 

 In none of them did I find any trace in the young 

 of an inborn, instinctive fear of the natural 

 enemies which were regarded with fear and terror 

 by the adult of the species. Young wild hares 

 and young wild rabbits showed no inborn fear of 

 either dogs or cats. Young wild rabbits and young 

 wild hares became as friendly and playful from the 

 beginning with specially trained cats to which they 

 were introduced as if they had been all of the same 

 species. Young rabbits, showing no inborn fear 

 of dogs, would frisk and play with the hereditary 

 enemy of their kind by whom their species had been 

 hunted for tens of thousands of generations. The 

 young of our common wild birds showed no inborn 

 fear of the cat when, fully fledged, they were under 

 proper conditions introduced to it for the first time. 

 Nor did they develop any fear afterwards. And 

 so also when they were introduced under similar 

 conditions to birds of prey like the hawk or the 

 carrion crow trained to friendly relations. 



If it be asked now whence comes the universal 

 and ineradicable fear of natural enemies, which is 

 present under natural conditions in the whole of the 

 adult members of the species in these cases, the 

 answer is of great interest. The conclusion which I 

 arrived at was that in the numerous typical wild 



