xiii VARIATION AND EVOLUTION 143 



tion, and provided that it is not directly harmful there is 

 no reason why it should not persist. In this way we are 

 released from the burden of discovering a utilitarian 

 motive behind all the multitudinous characters of living 

 .organisms. For we now recognise that the function of 

 natural selection is selection and not creation. It has 

 nothing to do with the formation of the new variation. 

 It merely decides whether it is to survive or to be 

 eliminated. 



One of the arguments made use of by supporters of the 

 older view is that drawn from the study of adaptation. 

 Animals and plants are as a rule remarkably well adapted 

 to living the life which their surroundings impose upon 

 them, and in some cases this adaptation is exceedingly 

 striking. Especially is this so in the many instances of 

 what is called protective coloration, where the animal 

 comes to resemble its surroundings ' so closely that it 

 may reasonably be supposed to cheat even the keenest 

 sighted enemy. Surely, we are told, such perfect adap- 

 tation could hardly have arisen through the mere sur- 

 vival of chance sports. Surely there must be some guid- 

 ing hand moulding the species into the required shape. 

 The argument is an old one. For John Ray that guiding 

 hand was the superior wisdom of the Creator : for the 

 modern Darwinian it is Natural Selection controlling the 

 direction of variation. Mendelism certainly offers no 

 suggestion of any such controlling force. It interprets the 



