Habit and histind. 443 



possible to produce. Suppose that we find evidence of a 

 gradually increasing application of intelligence to some 

 important life-activity, or a more and more defined stereo- 

 typing of some incompletely habitual or instinctive action ; 

 how are we to prove that the increment in either case is 

 due to the inheritance of individual acquisitions, not to the 

 selection of favourable innate (that is to say, germinal) 

 variations ? Such a hopeless task may at once be 

 abandoned. 



Are we, then, to leave the question as insoluble ? I 

 think not. It is still open to us to consider whether there 

 are any cases in which the inheritance of acquired modifica- 

 tions is a more probable hypothesis than the selection of 

 favourable germinal variations. Now, the acquisition of 

 an instinctive dread of man, and the loss of this instinctive 

 timidity under domestication, seem to be of this kind. 

 And yet I doubt whether the evidence on this head is con- 

 vincing. For the loss of instinctive timidity, Professor 

 Weismann may invoke the aid of panmixia. But if there 

 is truth v[\ what I have already urged on this head, pan- 

 mixia will not adequately account for the facts. On the 

 other hand, he may contend that the instinctive dread is 

 not due to the inheritance of individually acquired ex- 

 perience, but to the selection of the wilder birds and 

 animals through the persistent elimination of those which 

 are tame. And in support of this view, he may quote 

 Parwin himself, who says,* "It is surprising, considering 

 the degree of persecution which they have occasionally 

 suffered during the last one or two centuries, that the 

 birds of the Falklands and Galapagos have not become 

 wilder; it shows that the fear of man is not soon acquired." 

 It is questionable, however, whether this persecution, 

 admittedly occasional, can have much elimination value. 

 There is, however, the element of imitation and instruction 

 to be taken into account, and the difficulty of proving that 

 the timidity is really instinctive. It has frequently been 

 observed that birds become, after a while, quite fearless of 



* See Appendix to Mr. Eomanes's "Mental Evolution in Animals," p. 861. 



