The Preparation for Higher Life 



oldest of these eras is known as the Archaeozolc or the first 

 life. This era is estimated to embrace about one-half of 

 geologic time, or the period since sedimentation began to 

 take place. During this era, no fossil plants or animals are 

 found but there is evidence, based on the substance of the 

 deposits, that the simplest forms of plant and animal life 

 existed during this era. 



The next era is known as the Proterozoic or early life. 

 This era is estimated to embrace about one-fourth of geo- 

 logic time and still there is, as yet, no definite fossil plants 

 found but based on the substance of the deposits covering 

 this era of sedimentation, there existed the simplest forms 

 of plant life. It was during this era that the first known 

 fossil animals made their appearance. These early forms 

 of fossil animals embrace the protozoa, worm, sea scor- 

 pions, trilobites and others. The trilobites had advanced 

 to the stage of a three-lobed animal (tri-lob-ites), with a 

 mouth, a head, a protective shell, a digestive system, and a 

 method of reproduction. They inhabited the mud flats of the 

 ancient oceans, lagoons and rivers. In the original matrix 

 of these early animals they may be found in a crawling 

 position with body fully extended. They are also found in 

 a sleeping position doubled up with their tail and mouth 

 touching in the same manner as many of the present day 

 worms are found. This important group of marine crab- 

 like animals has been extinct for many millions of years yet 

 they form an important group and the fossil remains of the 

 more than 1,700 different families furnish much evidence of 

 the development of the various evolutionary steps in early 

 life. This group of animals was the first to develop eyes. 



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