CREATION BY EVOLUTION 



as sand millions of years ago, tells of ages when some of 

 the fishes were stranded in pools that at times dried up. 

 Under these circumstances some of them passed from gill- 

 breathing to lung-breathing animals and acquired paddle- 

 like legs suitable for scrambling about on land. 



Thus arose the first backboned animals that spent part 

 of their life on land and part in water^ — the amphibians, 

 which are now represented by the newts, salamanders, frogs, 

 and toads. Then, through more tribulation of drought and 

 desert in the Permian epoch, there came the equally cold- 

 blooded reptiles — lizards, crocodiles, alligators — animals 

 capable of living all their life on land. They found conditions 

 so easy that they literally swarmed over all lands and even 

 invaded the air as flyers and the sea as swimmers. They 

 increased immensely in bodily bulk until some of their latest 

 representatives in the Cretaceous period (the period of the 

 Chalk) were the biggest masses of flesh that ever lived on 

 land. 



A few of the more progressive of these reptiles rather early 

 began to show signs of becoming something better, and by 

 the time the giants of the group were worn out, the progres- 

 sives had become warm-blooded animals, with an improving 

 brain and very active legs. These were the mammals, 

 quadrupeds which soon began to suckle their young and 

 care for them in their youth. At the beginning of the 

 Tertiary period they took the place of the giant reptiles, 

 which had disappeared. Birds also took possession of the 

 air. 



During the Tertiary period the mammals occupied every 

 sphere of life on the land, and as they became more com- 

 pletely adapted to their surroundings their brains grew rela- 

 tively larger and more useful. As the flesh-eaters advanced 

 in power of jaw and in cunning, and as the vegetable-feeders 



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