A Story Outline of Evolution 



known — giant lizards, turtles, crocodiles, serpents, dino- 

 saurs, pterosaurs and many other "saurs." 



This was an age of physical combat among the giants 

 of all ages in their efforts to survive. The weaker were 

 conquered by the stronger and in turn the stronger were 

 conquered by the cunning of the weaker. Each group 

 played its part in the scheme of life and passed from the 

 stage of animal struggle yet leaving certain heritages for 

 the future life that was to come. Out of all the vast num- 

 bers of these that struggled for millions of years for sur- 

 vival, only four orders remain and these representatives are 

 the snakes, lizards, alligators and crocodiles. It has been 

 said that during this vast period of time, Nature made many 

 experiments and many mistakes. Adaptations that fit con- 

 ditions today could not fit conditions a hundred million years 

 ago for animal life has no part in geologic changes or 

 changes in climatic conditions except adaptations to meet 

 these changes. 



It is the purpose of this outline to show, not all, but only 

 a few of the successive steps which animal life has taken in 

 passing from the lower to the higher forms. What special 

 progress has this class made over the heritage of the past 

 that will be a heritage for all life that is to follow? To 

 enumerate some of the changes in progressive development 

 we find that, after emerging from the egg, the gill slits are 

 gone and the animals of this class breathe by lungs; that the 

 first evidence of parental protection for the offspring begin 

 to appear; that the eggs are larger and fewer in number and 

 that they have a hard or leathery shell; that the eggs are 

 deposited in protective nests or sand best suited to their 



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