To the Australians, on the other hand, much inferior to the Maoris, the larger area of their continent affords extensive deserts and steppes into which the natives have withdrawn and whither the whites do not care to follow. Hence mere area, robbed of every other favorable geographical circumstance, has contributed to the survival of the 230,000 natives in Australia. Similarly the Arawaks were early wiped out on the island of Cuba and the Caribs on San Domingo and the smaller Antilles by the truculent methods of the Spanish conquerors, while both stocks survive on the continent of South America. Even the truculent methods of the Spanish conquerors could make little impression upon the relatively massive populations of Mexico and Peru, whose survival and latter-day recovery of independence can be ascribed largely though not solely to their ample territorial base. So the vast area of the United States and Canada has afforded a hinterland of asylum to the retreating Indians, whose moribund condition, especially in the United States, is betrayed by their scattered distribution in small, unfavorable localities. On the other hand, the vast extent of Arctic and sub-Arctic Canada, combined with the adverse climatic conditions of the region, will guarantee the northern Indians a longer survival. In Tierra del Fuego, the encroachments of sheep-farmers and gold-miners from Patagonia twenty years ago, by fencing off the land and killing off the wild guanaco, threatened the existence of this animal and of the Onas natives of the island. These, soon brought to bay in that natural enclosure, attacked the farmers, whose reprisals between 1890 and 1900 reduced the number of the Onas from 2,000 to 800 souls.[307] [Sidenote: Contrast of large and small areas in bio-geography.] The same law holds good in bio-geography; here, too, area gives strength and a small territorial foothold means weakness. The native flora and fauna of New Zealand seem involved in the same process of extinction as the native race. The Maoris themselves have observed this fact and applied the principle to their own obvious fate. They have seen hardy imported English grasses offering deadly competition to the indigenous vegetation; the Norway rat, entering by European ships, extirpating the native variety; the European house fly, purposely imported and distributed to destroy the noxious indigenous species.[308] The same unequal combat between imported plants and animals, equipped by the fierce Iliads of continental areas, and the local flora and fauna has taken place on the little island of St. Helena, to the threatened destruction of the native forms.[309]