EVOLUTIONARY THEORIES lOl 



are interested in tlie primary development of protein-like sub- 

 stances. 



The investigation of open systems and the way in which 

 they develop is of great significance for the problem we 

 have been studying. These systems may serve as basis for 

 the development of metabolic activity, which is the form of 

 movement of matter characteristic of life. In this connection 

 the ^vorks of C. N. Hinshelwood,'^ I. Prigogine," J. W. S. 

 Pringle'* and others are of great interest. 



The most important, as well as the least studied, stage of 

 the evolutionary process under consideration would seem to 

 be the transition from the most complicated organic sub- 

 stances to the most primitive living organisms. This is the 

 most serious gap in oiu' knowledge. 



When we regard the organisation of any living thing, even 

 the simplest, it strikes us that this organisation is not only 

 very complicated but extraordinarily well adapted to the 

 fulfilment of the functions peculiar to life. It is directed 

 towards the continuous self-preservation and self-reproduc- 

 tion of the whole living system under given external con- 

 ditions. 



The emergence of such internal ' adaptation of form to 

 function ' can only be understood on the basis of the same 

 principles which cause the ' adaptation of form to function ' 

 in the structure of all the organs of all higher organisms. 

 That is to say, one must study the interactions between the 

 organism and its environment and apply the Darwinian 

 principle of natural selection. This new biological ^vay of 

 behaviour must have been developed in the inorganic world 

 as part of the process of the establishment of life and later 

 played a very important part in the development of all living 

 matter. 



A number of authors such as N. H. Horowitz^ ^ and M. 

 Calvin^^ are trying to apply the principles of evolution and 

 even natural selection to individual molecules. However, 

 other workers (N. Kholodnyi,^^ J. D. Bernal, J. B. S. Haldane, 

 G. Wald and A. Oparin*°) consider that multimolecular 

 systems (' subvital ' systems, to use Haldane's terminology) 

 must have been formed before life arose and that these were 

 converted into living things by natural selection. 



