INFLUENCES OF ENVIKON.MENT 133 



sions wo must remember that llie evidence which we have 

 points to the fact that neither environment nor trainiujj; 

 can produce, in the sense of originating, human charac- 

 teristics, o-ood or l>ad. But it is environment tliat deter- 

 mines wliether given characteristics, when l)orn into the 

 world, shall perish by starvation or conflict, or shall sur- 

 vive and perpetuate themselves in following generations. 



Perhaps the most obvious and rij^orous effect of phys- 

 ical environment is the selective influence exercised by 

 climatic gradations from extreme heat to extreme cold, 

 and from excessive aridity to excessive moisture. Phys- 

 ical environment sets limits to human habitation. Life 

 is maintained with great difficulty in the Arctic and Ant- 

 arctic regions. ^^ In the Torrid regions activities must be 

 confined to the comparative cool of the early morning 

 or the evening. The intense heat of mid-day makes in- 

 action necessary. 



The heat belt, that section of the globe lying roughly 

 between 30° north latitude and 30° south latitude where 

 the mean annual temperature is 68° Fahrenheit, is in- 

 habited by peoples who have during the last five hundred 

 years contributed little to human advancement. Tlie 

 natives of the tropics and sub-tropics, of Mexico, the 

 Central American republics, the West Indies, the greater 

 part of South America, practically the whole of Africa, 

 Arabia, India, Burma, Indo-China, the Malay Peninsula, 

 the Malay Archipelago, Polynesia, and the Philii)pine 

 Islands, have contributed an almost negligible addition 

 to art, literature, science and thought. It has been the 

 inhabitants of those countries which lie outside the heat 

 belt, the Continent; of Europe, the United Kingdom, the 

 United States, Canada, Australia, Central and Northern 



1* See figures 49 and 50. 



