THE NEW EVOLUTION 



date than those of the Cambrian period. But in so 

 far as these are determinable all of them, like the 

 fossils of the Cambrian, fall into major groups on the 

 basis of the definition of the major groups drawn up 

 from living types. 



The fact that these very early fossils are the remains 

 of calcareous algas, corals, crustaceans and protozoans 

 is simply correlated v^ith the circumstance that these 

 types of life, as is w^ell seen in the calcareous algas, 

 the corals and the foraminifera of the present day, 

 build exceptionally heavy skeletons. The existence 

 of these types alone in these very ancient rocks cannot 

 be regarded as indicating that no other types of life 

 existed in those ancient seas. 



Since all our evidence show^s that the phyla or major 

 groups of animals have maintained precisely the same 

 relation w^ith each other back to the time when the 

 first evidences of life appear, it is much more logical 

 to assume a continuation of these parallel interrela- 

 tionships further back into the indefinite past, to the 

 time of the first beginnings of life, than it is to assume 

 somewhere in early pre-Cambrian times a change in 

 these interrelationships and a convergence toward a 

 hypothetical common ancestral type from which all 

 were derived. This last assumption has not the 

 slightest evidence to support it. All of the evidence 

 indicates the truth of the first assumption. 



To this plain statement of fact the objection might 

 be raised "This is all very true so far as it goes, but 

 we must admit that the earliest evidences of life are 

 the traces of simple and primitive forms; and, anyway, 



[104] 



