A Story Outline of Evolution 



thus making him Immune to sun stroke. There have been 

 many thousands of plant and animal forms that have failed 

 to adapt themselves to changing conditions, and, as a con- 

 sequence, they have been cast into the discard and are now 

 extinct. 



The trilobites were the ancestors of the crabs and the 

 crabs were among the first to adapt themselves to life on 

 land. The trilobites had developed eyes, a shell or armour 

 covering the upper or exposed parts of the three lobes and 

 their heads, and a method of transportation. Legs with 

 hinged joints had come into being and such are now classi- 

 fied as Insects. They were at first water creatures and out 

 of these, the land insects were developed through adapta- 

 tion to the conditions surrounding them. Sea crabs became 

 land crabs, sea scorpions became land scorpions and In like 

 manner thousands of sea animals and insects left the sea and 

 adapted themselves to the conditions on land. But many 

 of these as we shall later see when we shall reach the age 

 of the mammal type of land animals forsook the land after 

 millions of years and returned again to life in the sea. 

 Swifter progress was now being made. Many of the land 

 insects were developing wings. These were not true wings 

 but were wings with a hinged joint. Among the greatest 

 of these were the huge dragon flies with a wing spread of 

 thirty Inches and a compound eye and the giant cock roaches 

 two or three feet in length. 



The law of Nature Is that animals shall live on one 

 another, either directly or Indirectly. In their "struggle for 

 existence'' Nature began far down the scale in both plant 

 and animal life to construct agencies of protection around 



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