CHAPTER I 



THE ORIGIN OF THE VOICE 



The great diversity of the voice in animals, and the 

 extent to which it is inflected by individuals, suggest 

 that it is particularly liable to be influenced by the 

 vicissitudes of the struggle for existence, and to 

 be necessarily modulated in accordance with the 

 requirements of each animal or species by which 

 it is employed. 



This modulation is very apparent. We hear 

 from every side the notes of various animals, as 

 cries for succour, songs apparently of love, and 

 notes equally suggestive of triumph or of fear — 

 all of them exactly suited to the purposes for 

 which they are uttered. But it does not follow 

 that these sounds have always been employed for 

 the same purposes, nor that they have always 

 been uttered in the present modes ; for we observe 

 among birds, at least, prevalent changes not only 



