DUCKS* LEGS AND WINGS. 55 



WINGS AND LEGS OF DUCKS AND FOWLS. 



The reduced wings and enlarged legs of domesti- 

 cated ducks and fowls are attributed by Darwin and 

 Spencer to the inheritance of the effects of use and 

 disuse. But the inference by no means follows. 

 Natural selection would usually favour these adap- 

 tive changes, and they would also have been aided 

 by an artificial selection which is often unconscious 

 or indirect. Birds with diminished power of flight 

 would be less difficult to keep and manage, and 

 in preserving and multiplying such birds man would 

 be unconsciously bringing about structural changes 

 which would easily be regarded as effects of 

 use and disuse. " About eighteen centuries ago 

 Columella and Varro speak of the necessity 

 of keeping ducks in netted enclosures like other 

 wild fowl, so that at this period there was danger 

 of their flying away." 1 Is it not probable that the 



1 Variation of Animals and Plants under Domestication, i. 292. 



