Man in the Light of Evolution 



forms were evolved. Out of the worm the first 

 fish was developed, and from these primitive am- 

 phibians and reptiles were evolved. Birds came 

 from a branch of the reptilian line. These are 

 only a few of the stages through which birds 

 were slowly evolved from unicellular animals 

 through long ages. 



The fowl, like every living being, comes from 

 an egg. The essential part of every egg is a 

 single cell. A very large part of the yolk of a 

 bird's egg and all the white is merely food to 

 support the growing embryo. Out of it the or- 

 gans must be builded and the energy furnished 

 for the long embryonic march or journey. 



How does the egg cell ever find its way 

 through this long march? How does it manage 

 to mold a body, frame a skeleton, stretch the 

 muscles, spin the marvelous cobweb of the ner- 

 vous system, and build a brain? If we had not 

 seen it happen so many times, we would never 

 believe that a chicken could be hatched out of 

 such a thing as an egg. 



This much would seem to be clear. The only 

 way in which the single cell of the t^^ can find 

 its way to, or succeed in building such a body, is 

 by an inherited tendency or impulse to follow 



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