12 



NATURE 



[September 5, 1912 



It is true that up to the present there is no evidence 

 of such happening ; no process of transition lias 

 hitherto been observed. But, on the other hand, is it 

 not equally true that the kind of evidence which would 

 be of any real value in determining this question has 

 not hitherto been looked for? We may be certain 

 that if life is being produced from non-living sub- 

 stance, it will be life of a far simpler character than 

 any that has yet been observed — in material which we 

 shall be uncertain whether to call animate or in- 

 animate, even if we are able to detect it at all, and 

 which we may not be able to visualise physically even 

 after we have become convinced of its existence.-- But 

 we can look with the mind's eye and follow in imagina- 

 tion the transformation which non-living matter may 

 have undergone and may still be undergoing to pro- 

 duce living substance. No principle of evolution is 

 better founded than that insisted upon by Sir Charles 

 Lyell, justly termed by Huxley "the greatest geologist 

 of his time," that we must interpret the past history 

 of our globe by the present ; that we must seek for 

 an explanation of what has happened by the study of 

 what is happening; that, given similar circumstances, 

 what has occurred at one time will probably occur at 

 another. The process of evolution is universal. The 

 inorganic materials of the globe are continually under- 

 going transition. New chemical combinations are 

 constantly being formed and old ones broken up ; new 

 elements are making their appearance and old elements 

 disappearing. =^ Well may we ask ourselves why the 

 production of living matter alone should be siibject 

 to other laws than those which have produced, and 

 are producing, the various forms of non-living matter ; 

 why what has happened may not happen. If living 

 matter has been evolved from lifeless in the past, we 

 are justified in accepting the conclusion that its evolu- 

 tion is possible in the present and in the future. 

 Indeed, we are not only justified in accepting this 

 conclusion, we are forced to accept it. When or where 

 such change from non-living to living matter may first 

 have occurred, when or where it may have' con- 

 tinued, when or where it may still be occurring, 

 are problems as difficult as they are interesting, but we 

 have no right to assume that they are insoluble. 



Since living matter always contains water as its 

 most abundant constituent, and since the first living 

 organisms recognisable as such in the geological 

 series were aquatic, it has generally been assumed that 

 life must first have made its appearance in the depths 

 of the ocean. =^ Is it, however, certain that the as- 

 sumption 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 evolutionarv transforma- 

 tion of non-living into living material as the waters 

 which surround it? Within this soil almost anv 

 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 

 i-hanges. 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 impos- 

 sible Jor 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 



-- " Spontaneous eenemlion of life could only be perceptually demon- 

 strated by filline in the lone terms of a series between the complex forms of 

 inorganic and the simplest forms of organic substance. Were this done, it 

 is quite possible that we should be unable to say (especially considering the 

 vagueness of our definitions of life) where life began or ended."— K. 

 Pearson, " Grammar of Science," second edition, 1900. p. 350. 



23 See on the production of elements, W. Crookes, Address to Section B, 

 Brit. .'Vssoc, 1886; T. Preston, Nature, vol. Ix., p. 180; J. J. Thomson, 

 Phil. Mag., 1897, p. 311; Norman Lockyer, oi.cit., 1900; G. Darwin! 

 Pres. Addr. Brit. .Association., 1905. 



For argtiments in favour of the first appearance of life having been in 



to follow its evolution. We are therefore not likely 

 to obtain direct evidence regarding such a trans- 

 formation 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 pateontological 

 series. This objection assumes that evolution would 

 in every case take an exactly similar course and pro- 

 ceed 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 matle 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 sub- 

 stance 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 ! 



Further Course of Evolution of Lije. 



Assuming the evolution of living matter to have 

 occurred — whether once only or more frequently 

 matters not for the moment — and in the form sug- 

 gested, viz., as a mass of colloidal slime possessing 

 the property of assimilation and therefore of growth, 

 reproduction would follow as a matter of course. For 

 all material of this physical nature — fluid or semi- 

 fluid in character — has a tendency to undergo sub- 

 division when its bulk exceeds a certain size. The 

 subdivision may be into equal or nearly equal parts, 

 or it may take the form of buds. In either case every 

 separated part would resemble the parent in chemical 

 and physical properties, and would equally possess the 

 property of taking in and assimilating suitable 

 material from its liquid environment, growing in bulk 

 and reproducing its like by subdivision. Omne vivum 

 e vivo. In this way from any beginning of living 

 material a primitive form of life would spread, and 

 would gradually people the globe. The establishment 

 of life being once effected, all forms of organisation 

 follow under the inevitable laws of evolution. Ce 

 n'est que le premier pas qui cotite. v 



We can trace in imagination the segregation of a 

 more highly phosphorised portion of the primitive 

 living matter, which we may now consider to have 

 become more akin to the protoplasm of organisms 

 with which we are familiar. This more phosphorised 

 portion might not for myriads of generations take 

 the form of a definite nucleus, but it would be com- 

 posed of material having a composition and qualities 

 similar to those of the nucleus of a cell. Prominent 

 among these qualities is that of catalysis — the func- 



S"' Lankester (Art. "Protozoa," " Encycl. Brit.." tenth edition) conceives 

 that the first protoplasm fed on the antecedent steps in its own evolutioit. 

 F. J. Allen (Brit. Assoc. Reports, rSgd) 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 exist- 

 ing organisms. He believes that " in accounting for the first origin of life 

 on this earth it is not necessary th.Tt, as Pfliiger assumed, the planet should 

 have been at a foimer period a blowing 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 



XO. 2236, VOL. 90] 



