Problems of Thermophilic Life in Polar Regions 157 



as Nuwiik Village at the tip of Point Barrow were littered with 

 decaying organic material. Even though the village had been 

 abandoned for nearly 35 years this litter showed a high ther- 

 mophile count. Grassy or mossy tundra type soil, on the other 

 liand, showed a relatively high count of mesophilic bacteria but 

 few thermophiles. 



The conclusion that we reached was that a high content 

 of organic material other than dead plants was necessary for the 

 growth or survival of thermophilic bacteria in polar regions. 



One cannot ignore the possibility of thermophilic bacteria 

 actually being normal polar soil microorganisms. It has been 

 demonstrated ( 3 ) that thermophilic bacteria can grow at reduced 

 temperatures in the soil. Whether they can actually multiply be- 

 low the freezing point as do mesophiles (7) needs to be de- 

 termined. 



One important point to remember when speaking of ther- 

 mophilic bacteria is that many of them are not obligately ther- 

 mophilic but grow very well at temperatures below 30 C. 



Before we overemphasize the importance of polar thermo- 

 philic bacteria we need to re-examine the soils and digestive 

 tracts of animals in the torrid and temperate zones for a variety 

 of types of thermophilic bacteria other than the aerobic spore- 

 formers. After learning what conditions are conducive to the 

 growth and suwival of thermophilic bacteria in warmer climates 

 I believe we can better understand why we find them or do 

 not find them in polar regions. 



There is a tendency to regard the microbiology of polar 

 regions as being unique. I believe, however, that when we study 

 similar environments in other regions we will find the outcome 

 of many of our polar studies to be predictable. 



REFERENCES 



1. Bartholomew, J. W., and Rittenberg, S. C: Thennophilic bacteria 



from deep ocean bottom cores. /. Bacterial., 57:658, 1949. 



2. Egorova, a. a.: Thermophile bacteria in Arctic. Compt. rend. (Dokladij) 



Acad. Sci. U.S.S.R., 79:649-650. 1938. 



3. Koch, A., and Hoffman, C: Uber die Verschiedenheit der Tempera- 



turanspiiiche thermophiler Bakterien im Boden und in kiinstlichen 



