A Story Outline of Evolution 



a baby cutting its teeth, they finally protrude. At a little 

 later date fore limbs develop in the same manner. The tail 

 which was used in swimming is now of no further use and 

 is therefore cast off. These limbs now serve as arms and 

 legs upon which are attached fingers and toes. Their lives 

 will be spent in and near the water and, because of this, 

 webs of skin are attached between the toes to aid them in 

 swimming. They are now able to swim, crawl and hop. 

 When approached upon the bank of a stream or pond, they 

 revert to their primitive instincts by jumping into the water 

 as a means of protection. 



If we shall notice a fresh water stream or pond in the 

 springtime, we can see the very processes of Evolution work- 

 ing before us. Fastened in strings upon the water weeds 

 or marshy grass may be found the eggs of frogs in the 

 process of incubating. In this act they are repeating all the 

 former life processes. From day to day we can see the 

 metamorphosis of the tadpole taking place — eyes and ears 

 developing, gills and tail disappearing, mouth opening, legs 

 protruding, the notochord changing to a jointed back-bone, 

 bones forming in the limbs and a skull forming as a protec- 

 tion to the brain. They change from gills to lungs, and 

 from a vegetable to an animal diet. Aill this is just repeat- 

 ing the life processes of millions of years in a few week's 

 time. 



Different environments have brought about different 

 habits among the various amphibia. Some have abandoned 

 the water as a place for depositing their eggs. Some of the 

 salamanders bring forth their young alive. In a few species 

 of tree toads that have abandoned the water, the eggs are 



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