70 THE THEORIES OF EVOLUTION 



unusual degree is more likely than others to survive. 

 . . . Clearly this highly useful power may be de- 

 veloped by natural selection. So also, for like rea- 

 sons, may quickness of vision and delicacy of hearing; 

 though it may be remarked in passing that since this 

 extra sense-endowment, serving to give early alarm, 

 profits the herd as a whole, which takes the alarm 

 from one individual, selection of it is not so easy, 

 unless it occurs in a conquering stag. . . . The 

 advantages which other members of the herd gain 

 from other slight variations may be equivalent. 

 This one has unusual agility and leaps a chasm which 

 others balk at. That one develops longer hair in 

 winter, and resists the cold better. Another has a 

 skin less irritated by flies, and can graze without so 

 much interruption. Here is one which has an un- 

 usual power of detecting food under the snow; and 

 there is one which shows extra sagacity in the choice 

 of a shelter from wind and rain. ... If these 

 other individuals severally profit by their small su- 

 periorities, and transmit them to equally large num- 

 bers of offspring, no increase of the variation in 

 question can take place; it must soon be cancelled." 13 

 In other words, no individual possesses on account 

 of certain advantages due to one character any actual 

 and complete superiority insuring its success at every 



13 The Inadequacy of Natural Selection, Contemporary Review: Feb. 

 and Mch., 1893. 



