the chase a semi-nomadic agriculture; and in a few districts where
geographic conditions had applied peculiar pressure, they had
accomplished the transition to sedentary agriculture.

[Sidenote: Land per capita under various cultural and geographic
conditions.]

Every advance to a higher state of civilization has meant a progressive
decrease in the amount of land necessary for the support of the
individual, and a progressive increase in the relations between man and
his habitat. The stage of social development remaining the same, the per
capita amount of land decreases also from poorer to better endowed
geographical districts, and with every invention which brings into use
some natural resource. The following classification[122] illustrates the
relation of density of population to various geographic and
socio-economic conditions.

Hunter tribes on the outskirts of the habitable area, as in Arctic
America and Siberia, require from 70 to 200 square miles per capita; in
arid lands, like the Kalahari Desert and Patagonia, 40 to 200 square
miles per capita; in choice districts and combining with the chase some
primitive agriculture, as did the Cherokee, Shawnee and Iroquois
Indians, the Dyaks of Borneo and the Papuans of New Guinea, 1/2 to 2
square miles per capita.

Pastoral nomads show a density of from 2 to 5 to the square mile;
practicing some agriculture, as in Kordofan and Sennar districts of
eastern Sudan, 10 to 15 to the square mile. Agriculture, undeveloped but
combined with some trade and industry as in Equatorial Africa, Borneo
and most of the Central American states, supports 5 to 15 to the square