Habits and Instincts of the Pairing Season. 229 



Observation, and that of a peculiarly difficult and 

 delicate nature, can alone decide whether there is such 

 elimination and such selection as is here suggested. 



I ain not sure that I have represented Mr. Hudson's 

 views correctly in saying that, as stated in the third 

 proposition, the instinctive element of the performance is 

 due to inheritance by direct transmission without elimina- 

 tion or selection. The essential question, however, is 

 this : Are we sure that the performances are instinctive ? 

 May not such essentially social procedures be handed on 

 by tradition without becoming ingrained in the congenital 

 nature ? We shall have occasion to see in the last chapter 

 that in human progress a greatly developed form of 

 tradition takes the place of heredity, and that evolution 

 is in large degree transferred from the organism to his 

 environment. May not tradition, in bird life and in the 

 animal world, suffice for the handing on of some habitual 

 activities ? This is another question which ignorance 

 prevents our answering with any certainty. No doubt we 

 have been wont to assume that these habitual activities 

 are instinctive and congenitally definite. But of decisive 

 and conclusive proof, there is in many cases little enough. 



In the case of bird-song there is some evidence, though 

 not so much as could be wished. We have already dis- 

 cussed it in the chapter on Imitation, and there saw that, 

 according to some observers, the singing of birds is, unlike 

 their call-notes and sounds of alarm, wholly traditional 

 and entirely due to imitation. This view could not, how- 

 ever, be unreservedly accepted without more conclusive 

 i vidonce. There may be congenital elements forming an 

 instinctive basis, requiring perhaps under normal con- 

 ditions the appropriate auditory stimulus provided by the 

 song of their own species, in the absence of which there 

 may be failure to sing at all, or imitation of alien strains 



