A Story Outline of Evolution 



This duckbilled water-mole represents a great advance- 

 ment over the highest form of reptile life and yet it is the 

 lowest form of the more than 10,000 species of the general 

 class toward which all evolutionary effort has been tending. 

 It has remained in its own blind alley during millions of years 

 because it has failed to change into a higher form. Nature 

 has been experimenting and calling new forces into use. 



Other living animal forms show us the next step in evolu- 

 tionary development. The opossums, kangaroos, certain 

 ant-eaters, the Tasmanian wolf and many small rodents 

 belong to this group. These have passed from the egg- 

 laying state but they have not reached the stage of advance- 

 ment where their young are born in a completely developed 

 state. They represent the order between hatching and true 

 birth. In this group, the young are partially developed 

 within the body of the mother and when they are born, they 

 are placed in a pouch on the under side of the mother's body, 

 each given a small teat to suck from which they are nourished 

 until they are ready to care for themselves. Even after they 

 leave the pouch, the mother cares for them and teaches them 

 in the art of securing food. The tails of the opossum are 

 without hair and still contain the atrophied scales of their 

 reptile ancestors. 



The opossum has developed the very peculiar deceiving 

 habit of feigning death when attacked by an enemy and it is 

 so persistent in this deceit that it will remain apparently life- 

 less while its bones are being crushed by a dog or other enemy. 

 This same deceiving habit is found among many of the inver- 

 tebrates. The kangaroos use their powerful hind legs in a 

 hopping process as a means of locomotion and by this method 



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