HOW PLANTS CAME TO DIFFER. 29 



hard to overtop its neighbour, and secure its fair 

 share of carbon and of sunshine. When a garden 

 is abandoned, you can very soon see the result of 

 this struggle ; for the flowers, which we only keep 

 alive by weeding that is to say, by uprooting 

 the sturdier competitors are soon overgrown 

 and killed out by the weeds that is to say, by 

 the stronger and better-adapted native plants of 

 the district. 



This, then, is the nature and meaning of these 

 two great principles. The Struggle for Life means 

 that more creatures are produced than there is 

 room in the world for. Natural Selection (or Sur- 

 vival of the Fittest) means that among them all 

 those which happen to be best adapted to their 

 particular circumstances oftenest succeed and 

 leave most offspring. 



By the action of the two great principles in 

 question (which affect all life, animal or vegeta- 

 ble) the world has been gradually filled with an 

 immense variety of wonderful and beautiful crea- 

 tures, all ultimately descended (as modern thinkers 

 hold) from the selfsame ancestors. The simple 

 little green jelly-speck, which is the primitive 

 plant, has given rise in time to the sea-weeds and 

 liverworts, then to the mosses and ferns, then to 

 the simplest flowering plants, thence to the shrubs 

 and trees, and finally to all the immense wealth 

 and variety of fruits, flowers, and foliage we now 

 see around us. 



The rest of this book will consist mainly of an 

 exposition of the results brought about among 

 plants by Variation, the Struggle for Life, and 

 Survival of the Fittest. But before we go on to 

 examine them in detail, I shall give just a few 



