NATURAL SELECTION 181 



Sexual /Selection 



Inasmuch as peculiarities often appear under domesti- 

 cation in one sex and become tiereditarily attached to 

 that sex, so no doubt it will be under nature. Thus 

 it is rendered possible for the two sexes to be modified 

 through natural selection in relation to different habits 

 of life, as is sometimes the case; or for one sex to 

 be modified in relation to the other sex, as commonly 

 occurs. This leads me to say a few words on what 

 I have called Sexual Selection. This form of selec- ^4 

 tion depends, not on a struggle for existence in re- 

 lation 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 com- 

 petitor, but few or no offspring. Sexual selection is, 

 therefore, less rigorous than natural selection. Generally, 

 the m3t_yi^orou^_nialeSj__th^ for 



t^eir places jja^j)^ture,_m^ But in 



many cases, victory depends not so much on general 

 vigor as on having special weapons, confined to the male . ; . 

 sex. A hornless stag or spurless cock would have a 

 poor chance of leaving numerous offspring. Sexual se- 

 lection, by always allowing the victor to breed, might 

 surely give indomitable courage, length to the spur, and 

 strength to the wing to strike in the spurred leg, in 

 nearly the same manner as does the brutal cockfighter 

 by the careful selection of his best cocks. How low in 

 the scale of nature the law of battle descends I know 

 not; male alligators have been described as fighting, bel- 

 lowing, and whirling round, like Indians in a war-dance, 



