EVOLUTIONARY THEORIES 95 



article"*^ which was very significant in the development of 

 the study of the origin of Hfe. This author also showed that 

 the development of organic compounds took place before 

 the formation of the first living things and took an evolution- 

 ary view of this process. 



Afterw^ards, when it was found that the atmosphere of 

 the large planets contained hydrocarbons which can only 

 have been formed there abiogenically,*^ the hypothesis that 

 organic compounds were formed similarly on the Earth 

 became generally accepted. It must not be supposed, how- 

 ever, that this meant a complete victory for the evolutionary 

 over the metaphysical school of thought in relation to the 

 problem of the origin of life. On the contrary, very many 

 workers on the problem in the thirties and even the forties 

 of this century only applied the evolutionary principle to 

 the origin and development of organic substances. They only 

 accepted organic chemical evolution. They discussed the 

 most important event — the transition from the lifeless to 

 the living state — from a fundamentally metaphysical stand- 

 point, regarding it as the sudden appearance of ' living mole- 

 cules ', particles of viruses or genes, which were endowed 

 with all the attributes of life from their very formation. 



This approach to the solution of the problem of the origin 

 of life was basically that which is associated with the works 

 of T. H. Morgan^^ and his followers, on the ' genie ' nature 

 of life. 



According to Morgan the first organic things which showed 

 signs of life w^ere genes. In his paper The gene as the basis 

 of life H. J. MuUer** described this basis as a particle of 

 matter endowed with a definite chemical structure, a giant 

 molecule w^hich is so chemically stable that it has retained 

 its internal, life-determining structure essentially unchanged 

 throughout the whole development of life on the Earth from 

 times ' before green slime bordered the seas ' right up to 

 the present. According to Muller, life did not arise before 

 the gene. The first things which were able to grow, from 

 which arose a substance like that which exists at present, 

 probably consisted almost exclusively of the gene or genes 

 already mentioned. Thus, genes formed the basis of the first 

 living things. 



