Note 214 — Chapter IV · —The Movements Of Peoples In Their Geographical Significance

Contrasted environments effect a natural selection in another way and thereby greatly stimulate differentiation, whenever an intruding people contest the ownership of the territory with the inhabitants. The struggle for land means a struggle also for the best land, which therefore falls to the share of the strongest peoples. Weaklings must content themselves with poor soils, inaccessible regions of mountain, swamp or desert. There they deteriorate, or at best strike a slower pace of increase or progress. The difference between the people of the highlands and plains of Great Britain or of France is therefore in part a distinction of race due to this geographical selection,214 in part a distinction of economic development and culture due to geographic influences. Therefore the piedmont belts of the world, except in arid lands, are cultural, ethnic and often political lines of cleavage, showing marked differentiation on either side. Isotherms are other such cleavage lines, marking the limits beyond which an aggressive people did not desire to expand because of an uncongenial climate. The distinction between Anglo-Saxon and Latin America is one of zone as well as race. Everywhere in North America the English stock has dominated or displaced French and Spanish competitors down to the Mexican frontier.