STRUGGLE FOR EXISTENCE 57 



mistletoe ; and only a little less plainly in the humblest 

 parasite which clings to the hairs of a quadruped or 

 feathers of a bird ; in the structure of the beetle which 

 dives through the water ; in the plumed seed which is 

 wafted by the gentlest breeze ; in short, we see beauti- 

 ful adaptations everywhere and in every part of the 

 organic world. 



Again, it may be asked, how is it that varieties, which 

 I have called incipient species, become ultimately con- 

 verted into good and distinct species, which in most 

 cases obviously differ from each other far more than do 

 the varieties of the same species ? How do those groups 

 of species, which constitute what are called distinct 

 genera, and which differ from each other more than do 

 the species of the same genus, arise ? All these results, 

 as we shall more fully see in the next chapter, follow 

 from the struggle for life. Owing to this struggle for 

 life, any variation, however slight, and from whatever 

 cause proceeding, if it be in any degree profitable to an 

 individual of any species, in its infinitely complex rela- 

 tions to other organic beings and to external nature, 

 will tend to the preservation of that individual, and 

 will generally be inherited by its offspring. The off- 

 spring, also, will thus have a better chance of surviving, 

 for, of the many individuals of any species which are 

 periodically born, but a small number can survive. 

 1 have called this principle, by which each slight vari- 

 ation, if useful, is preserved, by the term of Natural 

 Selection, in order to mark its relation to man's power 

 of selection. We have seen that man by selection can 

 certainly produce great results, and can adapt organic 

 beings to his own uses, through the accumulation of 

 slight but useful variations, given to him by the hand of 

 Nature. But Natural Selection, as we shall hereafter 

 see, is a power incessantly ready for action, and is as 

 immeasurably superior to man's feeble efforts, as the 

 works of Nature are to those of Art. 



We will now discuss in a little more detail the struggle 

 for existence. In my future work this subject shall be 

 treated, as it well deserves, at much greater length. 



