THE STRUGGLE FOR FOOD AND ROOM 275 



tions of life, such as cold and heat, and drouth and flood. 

 No living being can escape from this struggle. Each 

 strives to feed itself, to save its own life, to produce and 

 protect its young. But in spite of all their efforts only a 

 few individuals out of the hundreds and thousands born 

 live to maturity. The great majority are killed in the 

 Qgg stage, or during adolescence. 



Selection by nature. — What individuals survive of the 

 many which are born.-' Those best fitted for life; those 

 which are a little stronger, a little swifter, a little hardier, 

 a little less readily perceived by their enemies than the 

 others. We know from our observation of a brood of 

 young kittens or puppies that there are differences in new- 

 born individuals of the same kind, and even among those 

 born from the same mother. Thus it is with all animals. 

 No two individuals even in the same brood are exactly 

 alike at birth. And the very few members of each brood 

 which do survive are almost always the hardier, stronger, 

 and swifter. They are the winners in the struggle for 

 existence. And this survival of the fittest, as it is called, 

 is practically a weeding out or selecting process of Na- 

 ture. She selects the fittest to live and to perpetuate 

 their kind. Their young in turn must undergo the strug- 

 gle and the selecting process, and again the fittest live. 

 And so on until the adjustment or harmonizing of the 

 bodies and habits of animals with the conditions of their 

 life, their environment, comes to be extremely fine and 

 nearly perfect. 



Special means to get food. — With such a constant 

 struggle, such a race for food, it is not strange that we 

 find different animals having various kinds of special 

 arrangement for getting it. Those which live on plants 

 can get it in two ways, either by biting off the green 

 leaves and stems and crushing them in the mouth, or by 

 thrusting a sucking beak into the plant tissue and draw- 



