CHAPTER II 



THE STRUGGLE FOR EXISTENCE 



Its importance — The struggle among plants — Among animals — Illustrative 

 cases — Succession of trees in forests of Denmark — The struggle for 

 existence on the Pampas — Increase of organisms in a geometrical 

 ratio — Examples of great powers of increase of animals — Rapid 

 increase and wide spread of plants — Great fertility not essential to 

 rapid increase — Struggle between closely allied species most severe — 

 The ethical aspect of the struggle for existence. 



There is perhaps no phenomenon of nature that is at once 

 so important, so universal, and so little understood, as the 

 struggle for existence continually going on among all organ- 

 ised beings. To most persons nature appears calm, orderly, 

 and peaceful. They see the birds singing in the trees, the 

 insects hovering over the flowers, the squirrel climbing among 

 the tree-tops, and all living things in the possession of health 

 and vigour, and in the enjoyment of a sunny existence. But 

 they do not see, and hardly ever think of, the means by which 

 this beauty and harmony and enjoyment is brought about. 

 They do not see the constant and daily search after food, the 

 failure to obtain which means weakness or death; the con- 

 stant effort to escape enemies ; the ever -recurring struggle 

 against the forces of nature. This daily and hourly struggle, 

 this incessant warfare, is nevertheless the very means by which 

 much of the beauty and harmony and enjoyment in nature is 

 produced, and also affords one of the most important elements 

 in bringing about the origin of species. We must, therefore, 

 devote some time to the consideration of its various aspects 

 and of the many curious phenomena to which it gives rise. 



It is a matter of common observation that if weeds are 

 allowed to grow unchecked in a garden they will soon destroy 



