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502 houses and towns being relegated to waste places. The temperate food plants of Peru and China are all apparently indigenous to their respective continents. They testify to the independent development of the temperate agricultures of the two regions, but it seems certain that both were the successors of more tropical starch-eating populations, parts of which had been crowded back to the relatively inhospitable plateaus of Peru and Bolivia, and to the bleak plains of northern China, where the primitive tropical root-crops were, of necessity, replaced by more hardy indigenous species. The Chibcha people of the interior of Colombia attained a considerable degree of advancement without adopting a single domestic animal. The Peruvians and Chinese learned to use beasts of burden and animal fibers and skins, but their pastoral efforts were merely incidental to agriculture; they remained essentially vegetarians, eating little meat, and never taking up the use of milk.

In further support of the suggestion that the use of the starch-producing root-crops is a distinctively American development of primitive agriculture is the fact that the tropics of the old world contributed no important cultivated plant of this class, and none which gives evidence of long domestication. On the other hand, such regions as Madagascar and East Africa, where Polynesians are now supposed by ethnologists to have settled in 'remote prehistoric times,' continued the culture and differentiation of the varieties of the taro and the sweet potato, and were agriculturally mere outposts of the American tropics.

The presence of the banana might be thought to explain the relatively small importance of root-crops in the old world, since it furnishes with far less effort of cultivation and preparation a highly nutritious and palatable food. It appears, however, that the use of root-crops must have preceded the domestication of the banana, for although the peed-bearing wild bananas are utterly worthless as fruits and hence would not have been domesticated as such, nevertheless more species of them than of any other genus of food plants were brought into cultivation. The clue to this paradox is afforded by the fact that bananas are still cultivated as root crops in the old world tropics, particularly in New Caledonia and Abyssinia.