146 CHARLES DARWIN 



any decorative or alluring adjunct not equally snared 

 by the other, Darwin attributed this special gift either 

 to the law of battle, or to the long and slowly exerted 

 selective action of their fastidious mates. 



The germ of the doctrine of sexual selection is to be 

 found, like so many other of Charles Darwin's theories, 

 in a prophetic passage of his grandfather's ' Zoonomia.' 

 Stags, the Lichfield physician tells us, are provided with 

 antlers ' for the purpose of combating other stags for 

 the exclusive possession of the females, who are ob- 

 served, like the ladies in the time of chivalry, to attend 

 the car of the victor. The birds which do not carry 

 food to their young, and do not therefore marry, are 

 armed with spurs for the purpose of fighting for the 

 exclusive possession of the females, as cocks and quails. 

 It is certain that these weapons are not provided for 

 their defence against other adversaries, because the 

 females of these species are without this armour. The 

 final cause of this contest among the males seems to be 

 that the strongest and most active animal should propa- 

 gate the species, which should thence become improved.' 



It must be noticed, however, that Erasmus Darwin 

 here imports into the question the metaphysical and 

 Ideological notion of the final cause, implying that the 

 struggle of the males was ordained from without, for 

 this express and preconceived purpose ; whereas Charles 

 Darwin, never transcending the world of phenomena, 

 more logically regards the struggle itself as an efficient 

 cause, having for its result the survival of the strongest 

 or the handsomest as the case may be. This distinction 

 is fundamental ; it marks the gulf between the essen- 

 tially teleological spirit of the eighteenth century and 



