LIFE: ITS NATURE, ORIGIN AND MAINTENANCE 19 



Is it, however, certain that the assumption that life originated in the sea 

 is correct ? Is not the land-surface of our globe quite as likely to have 

 been the nidus for the evolutionary transformation of non-living into 

 living material as the waters which surround it ? Within this soil almost 

 any chemical transformation may occur ; it is subjected much more 

 than matters dissolved in sea-water to those fluctuations of moisture, 

 temperature, electricity, and luminosity which are potent in producing 

 chemical changes. But whether life, in the form of a simple slimy 

 colloid, originated in the depths of the sea or on the surface of the land, 

 it would be equally impossible for the geologist to trace its beginnings, 

 and were it still becoming evolved in the same situations, it would be 

 almost as impossible for the microscopist to follow its evolution. We 

 are therefore not likely to obtain direct evidence regarding such a 

 transformation of non-living into living matter in Nature, even if it is 

 occurring under our eyes. 



An obvious objection to the idea that the production of living matter 

 from non-living has happened more than once is that, had this been the 

 case, the geological record should reveal more than one palaeontological 

 series. This objection assumes that evolution would in every case take 

 an exactly similar course and proceed to the same goal an assumption 

 which is, to say the least, improbable. If, as might well be the case, 

 in any other palaeontological series than the one with which we are 

 acquainted the process of evolution of living beings did not proceed 

 beyond Protista, there would be no obvious geological evidence regarding 

 it; such evidence would only be discoverable by a carefully directed 

 search made with that particular object in view.* I would not by any 

 means minimise the difficulties which attend the suggestion that the 

 evolution of life may have occurred more than once or may still be 

 happening, but on the other hand, it must not be ignored that those 

 which attend the assumption that the production of life has occurred 

 once only are equally serious. Indeed, had the idea of the possibility 

 of a multiple evolution of living substance been first in the field, I 

 doubt if the prevalent belief regarding a single fortuitous production 

 of life upon the globe would have become established among biologists- 

 so much are we liable to be influenced by the impressions we receive in 

 scientific childhood ! 



see A. B. Macallum, ' The Palseochemistry of the Ocean,' Trans. Canad. Instit., 

 1903-4. 



* Lankester (Art. 'Protozoa,' Encycl. Brit., tenth edition) conceives that the first 

 protoplasm fed on the antecedent steps in its own evolution. F. J. Allen (Brit. Assoc. 

 Reports, 1896) comes to the conclusion that living substance is probably constantly 

 being produced, but that this fails to make itself evident owing to the substance being 

 seized and assimilated by existing organisms. He believes that ' in accounting for the 

 first origin of life on this earth it is not necessary that, as Pfluger assumed, the planet 

 should have been at a former period a glowing fire-ball.' He 'prefers to believe that 

 the circumstances which support life would also favour its origin.' And elsewhere : 

 ' Life is not an extraordinary phenomenon, not even an importation from some other 

 sphere, but rather the actual outcome of circumstances on this earth.' 



