Crops and Animals - Harvesting the Biosphere - page 105

Table 8.1
Density of Human Populations

Population Density
(people/km 2 ) Live Weight (kg/ha)

Foraging 0.01- > 1 0.005-0.5

Pastoralism 1-2 0.5-1

Shifting cultivation 20-30 9-14

Traditional farming
Predynastic Egypt 100-110 45-50

Medieval England 150 75

Global mean in 1900 200 100

Chinese mean in 1900 400 180

Modern agriculture
Global mean in 2000 400 200

Chinese mean in 2000 900 410

Jiangsu province in 2000 1,400 630

Note: All densities for foragers and pastoralists are per unit of exploited of land; all densities
for traditional and modern agriculture are per unit of arable land.

through these actions. That conclusion is debatable, but there can be no doubt
about the large-scale and often lasting environmental transformations brought
about by pastoralism and cropping. And these changes affected not only fertile
river valleys, coastal lowlands, or forests near growing population centers but even
Amazonia, a region that was considered until recently the very epitome of undis-
turbed nature.
The transition to permanent cropping involved a complex mix of natural and
social factors. The climate was too cold and CO 2 levels were too low during the
late Paleolithic, but the subsequent warming, as Richerson, Boyd, and Bettinger
(2001) put it, made agriculture mandatory in the Neolithic. After all, between
10,000 and 5,000 years before the present, agriculture had evolved independently
in at least seven locations on three continents (Armelagos and Harper 2005). At the
same time, the importance of cultural factors is undeniable, as sedentary farming
fostered association and more complex social relations, promoted individual owner-
ship and the accumulation of material possessions, and made both defense and
aggression easier—but Orme (1977) went too far when he argued that food produc-
tion as an end in itself may have been relatively unimportant.
Traditional low-yield cropping was the dominant subsistence mode in all prein-
dustrial societies. Its practice shared some notable universal commonalities: grains