DARWINISM DEFENDED. 183 



"But with all this criticism of utility it must be recognised that 

 the agency of utility as determining survival is becoming more 

 significant as discussion proceeds. We have seen that it must be 

 admitted that all characters to be affected by the principle of 

 survival, must have selective value : i. e., must affect the matter of 

 life and death. But this demand does not prove to be so serious 

 when we recognise that natural selection works upon general 

 averages rather than individuals. Those who find the selection 

 principle such a great factor insist that all characters have selective 

 value if they have any value at all. If a character has the value 

 of even rendering its possessor a little more comfortable, they tell 

 us it will eventually be subject to the principle of survival at the 

 expense of non-favoured animals. The substitution of old types 

 by new ones is not a matter of a single generation, but many 

 generations. In such a long history there must be innumerable 

 conditions where any character, even the slightest, may have been 

 of use enough to give its possessors an advantage over others. It 

 is not necessary to believe that a character should preserve its 

 possessor, while all non-favoured individuals perish, in order to 

 consider that the character has selective value. Considering that 

 the origin of species is a matter extending over hundreds of years 

 and many generations, even little things will count in the long run. 

 If an animal has a slight advantage over another, which simply 

 gives it more comfort and enables it to obtain its food with a little 

 less exertion, this may tell permanently in the struggle, since such 

 an individual will have more energy to put into reproduction, and 

 hence may leave a larger number of offspring. The other non- 

 favoured individuals may not, indeed, be exterminated without off- 

 spring, but may simply produce less offspring. In this struggle for 

 permanency, the individuals which have the largest number of 

 offspring, other things being equal, will inevitably come out ahead, 

 and the others in time disappear. 



"An example will make this clearer. A difference of an inch or 

 two in the length of a cow's tail seems a matter decidedly too 

 small to base the selection principle upon. Can it be imagined 

 that the lengthening of the tail by a couple of inches can be of 

 selective value? Can we honestly believe that these two inches will 

 determine that the longer-tailed cow will live and produce off- 

 spring, while the shorter-tailed individuals will die? Only thus, 

 however, can we assume that the tail has been developed by natural 

 selection. Now this example, which seems to be an extreme case 

 of slight utility, may show us how it is possible, upon the principle 

 of the selection of averages, to conceive that characters of slight 

 use may be preserved by natural selection. It is not necessary to 



