Darwinism stated by Darwin himself · Charles Darwin
DEVELOPMENT OF THE EAR FOR MUSIC.
Therefore, as far as the mere perception of musical notes is concerned, there seems no special difficulty in the case of man or of any other animal. But if it be further asked why musical tones in a certain order and rhythm give man and other animals pleasure, we can no more give the reason than for the pleasantness of certain tastes and smells. That they do give pleasure of some kind to animals we may infer from their being produced during the season of courtship by many insects, spiders, fishes, amphibians, and birds; for, unless the females were able to appreciate such sounds and were excited or charmed by them, the persevering efforts of the males and the complex structures often possessed by them alone would be useless; and this it is impossible to believe.
Text from Project Gutenberg, public domain in the United States.