Darwin s Theory of Sexual Selection 213 



and as a gibbon, one of the anthropomorphous apes, pours 

 forth a whole octave of musical notes and may be said to 

 sing, it appears probable that the progenitors of man, either 

 the males or females or both sexes, before acquiring the 

 power of expressing their mutual love in articulate language, 

 endeavored to charm each other with musical notes and 

 rhythm. So little is known about the use of the voice by 

 the Quadrumana during the season of love, that we have no 

 means of judging whether the habit of singing was first 

 acquired by our male or female ancestors. Women are 

 generally thought to possess sweeter voices than men, and as 

 far as this serves as any guide, we may infer that they first 

 acquired musical powers in order to attract the other sex. 

 But if so, this must have occurred long ago, before our ances- 

 tors had become sufficiently human to treat and value their 

 women merely as useful slaves. The impassioned orator, 

 bard, or musician, when with his varied tones and cadences 

 he excites the strongest emotions in his hearers, little 

 suspects that he uses the same means by which his half- 

 human ancestors long ago aroused each other's ardent pas- 

 sions during their courtship and rivalry." 



We have now examined in some detail the evidence that 

 Darwin has brought forward in support of his hypothesis of 

 sexual selection. A running comment has been made while 

 considering the individual cases, but it may be well to sum 

 up the matter by briefly indicating the reasons why the hy- 

 pothesis seems incompetent to explain the facts. 



General Criticism of the Theory of Sexual Selection 



1. Some of the objections that apply to the theory of 

 natural selection apply also with equal force to the theory of 

 sexual selection in so far as the results in both cases are sup- 

 posed to be the outcome of the selection of individual, or 

 fluctuating, variations. If these variations appear in only 



