Nature of Evolutionary Progress 53 



were originally one; they had a common origin. 

 Whether all existing organisms had thus a common 

 origin is doubtful. But from the uniformities seen in 

 the fine structure of their cells and chromosomes, it 

 seems clear that the animals, along with perhaps the 

 higher plants, all came from a single center. They 

 were once a single mass, simple in character, perhaps 

 somewhat like the protoplasm of an amoeba. This 

 original gi'eat organism has become separated into 

 many pieces, of which each of us is one. The dog that 

 follows me on the street, the bird to whose song I 

 listen, the mosquito that I try to drive from my face, 

 the inf usorian that I see under the microscope — these, 

 like myself and yourself, are pieces of that original 

 organic mass. We are all in that real sense brothers ; 

 we are in literal truth children of the same original 

 parent ; we are all one flesh ; we are pieces of the same 

 original organic material. A constant realization of 

 that fact is the clue that must guide us in our inter- 

 pretation of the world of Hfe. With St. Francis, we 

 must realize always that the birds and beasts are our 

 brothers. 



These pieces, these brothers, which were originally 

 one, and thus were all creatures of the same kind, 

 have since developed in many different directions 

 until there have been produced the great number of 

 diverse types that exist now : insects, Crustacea, birds, 

 men, and thousands of others. 



Thus the progressive changes that are one of the 

 great characteristics of life do not occur in a single 

 direction but in many directions. There is a copious 



