' 19 20 ] Townsend, Courtship in Birds. Sol 



reasonable and very human point of view. This is what leads to 

 courtship, and in this courtship rivalry it is natural to suppose 

 that the best bird wins. Although it has been somewhat the fash- 

 ion of late to decry Darwin's theory of sexual selection and to 

 substitute others for it, its simplicity and common sense still ap- 

 peal to many, and it is worth while occasionally to consult the 

 original text. 



Darwin published his 'Origin of Species' in 1859. In Chapter 

 IV he says he is led " to say a few words on what I have called 

 Sexual Selection. This form of selection depends, not on a struggle 

 for existence in relation to other organic beings or to external 

 conditions, but on a struggle between the individuals of one sex, 

 generally the males, for the possession of the other sex. The 

 result is not death to the unsuccessful competitor, but few or no 

 offspring. Sexual selection is, therefore, less rigorous than natural 

 selection. Generally, the most vigorous males, those which are 

 best fitted for their places in nature, will leave most progeny. 

 But in many cases, victory depends not so much on general vigor, 

 as on having special weapons confined to the male sex. A horn- 

 less stag or spurless cock would have a poor chance of leaving 

 numerous offspring. 



"Amongst birds, the contest is often of a more peaceful char- 

 acter. All those who have attended to the subject, believe that 

 there is the severest rivalry between the males of many species to 

 attract, by singing, the females. The rock-thrush of Guiana, 

 birds of paradise, and some others, congregate; and successive 

 males display with the most elaborate care, and show off in the 

 best manner their gorgeous plumage; they likewise perform strange 

 antics before the females, which, standing by as spectators, at 

 last choose the most attractive partner. 



"I cannot here enter on the necessary details; but if man can 

 in a short time give beauty and an elegant carriage to his bantams, 

 according to his standard of beauty, I can see no good reason to 

 doubt that female birds, by selecting, during thousands of genera- 

 tions, the most melodious or beautiful males, according to their 

 standard of beauty, might produce a marked effect." 



Eliot Howard,' on the other hand, believes that display and 

 extravagant bodily antics are merely "reflex actions directly re- 



i The British Warblers. 



