286 ANNUAL REPORT SMITHSONIAN INSTITUTION, 195 3 



Since most of the heat loss comes through the skin, the larger the 

 animal, all else being equal, the easier the process of keeping it warm. 

 Other factors, some of which will be dealt with presently, enter into 

 this picture, and if they and others still to be determined did not, it 

 would be more than a rule. 



The simplest test of Bergmann's rule is to compare mean body 

 weight ^ of different human popvilations with climate as expressed 

 by latitude. In Europe a regular cline is found between the peoples 

 of the northwest, as the Irish with 157 pounds and the Finns with 

 154, down to the Spaniards with 132 and the racially white Berbers 

 of Algeria with 124 pounds. In Asia the Mongoloid peoples show 

 the same tendency, with the North Chinese weighing 142 and the 

 Annamites 112 pounds, respectively. In America the Eastern Aleuts 

 average 150 j^ounds, a level maintained by most of the Indians of 

 the northern United States and Canada, while the Maya of Central 

 America tip the scales at only 119 pounds. In South America weight 

 rises with altitude and latitude to a peak among the bulky Indians 

 of Patagonia and the grasslands of Tierra del Fuego. The equatorial 

 Andamanese weighed only 08 pounds, the Kalahari Bushmen 89. The 

 Baluba, a non-Pygmy Negro tribe of the Belgian Congo, average only 

 118 pounds, which seems to be par for tropical rain forests. In 

 F'olynesia, where offshore breezes make heat loss no problem, weights 

 are high, as they are in cool New Zealand. Polynesian figures range 

 from 140 pounds upward. Indonesians, to whom Polynesians are 

 supposed to be related, are 20 to 30 pounds lighter. Their islands are 

 hotter. 



It can be easily demonstrated that changes in body size may take 

 place in a single generation. Whatever genetic mechanisms control 

 weight permit a useful capacity for variation. Man's size is as plastic 

 as his tannable skin color and as automatically regulated. Anyone 

 who has visited the Lower Amazon country has seen that the Brazilian 

 citizens in that tropical forest are of one size, whatever their hair 

 form, skin color, or cast of facial features. At least three racial 

 stocks arc concerned, the Mediterranean, Negro, and American Indian. 

 All come out the same size. Farther south representatives of these 

 same three stocks are much larger. 



One other environmental factor affects body size, causing different 

 populations within a given climatic zone to vary within their limits 

 of tolerance. That is nutrition. In my North Albanian series (Coon, 

 1950) I found that the tribesmen living on food raised on granitic 

 soil were significantly smaller than those who walked over limestone, 

 thus confirming the results of French investigators more than half 



8 Baker, 1953;, Coon, 1939; Hiernaux, 1952; HootoD, 1928; Howells, 1937; Russell W. 

 Newman, 1952b ; Rodahl and Edwards, 1952 ; Weidenreich, 1943. 



