476 FURTHER EVOLUTION 



organisms acquired the ability to use a greater variety of 

 sources of energy than previously. This laid the basis for the 

 origin of autotrophy, the culminating development of which 

 was the photosynthesis developed by green plants, which 

 involved in the process of life that inexhaustible source of 

 energy, sunlight. 



Photosynthesis led to the creation of an abundance of 

 organic substances and of an oxygen-containing atmosphere 

 on the Earth. These formed the basis for the origin of the 

 world of animals with their extremely intensive respiratory 

 metabolism and their rapid, progiessive development of 

 organic forms which, in the long run, led to the appearance 

 on our planet of a thinking being, man. 



The contemporary process of the evolution of living things 

 is, in principle, nothing but a series of further links in that 

 unending chain of transformations of matter which began 

 in the earliest stage of the existence of the Earth. 



BIBLIOGRAPHY TO CHAPTER IX 



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3> 645 (1949)- 

 J. Baddiley, G. Ehrensvard, E. Klein^ L. Reio and E. 



Saluste. /. hiol. Chem., 18^, ']']'] (1950). 



G. Ehrensvard. Svensk kem. Tidskr., 66, 249 (1954) ; Ann. 



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2. (V. 200). 



G. R. Greenberg. Fed. Proc, 8, 202 (1949) ; P^ 179 (1950)- 

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3. (V. 192). 



4. N. H. Horowitz. Proc. nat. Acad. Sci., Wash., ^i, 153 



(1945)- 



5. C. B. van Niel. Physiol. Rev., 2^, 338 (1943). 



6. (VIII. 64). 



7. R. P. Hall. Quart. Rev. Biol., 14, 1 (1939). 



8. A. LwoFF (ed.). Biochemistry and physiology of Protozoa. 



New York, 1951. 



9. A. LwoFF. L'evolution physiologique. £tude des pertes de 



fonctions chez les microorganismes. Actualites sci. 

 ind., no. 970 (1944) ; Recherches biochimiques sur la 

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 Pasteur. Paris, 1932. 



