This unit examines the origins of agriculture and its subsequent diffusion. Students learn about the ways agricultural practices have changed over time as a result of technological innovations, such as equipment mechanization and improvements in transportation that create global markets. In addition, they examine the consequences of agricultural practices such as the use of high-yield seeds and chemicals, revisiting the human–environmental relationships studied in Unit 1.
Course emphasis on spatial patterns is evident in this unit as students consider the differences in what foods or resources are produced and where they are produced. These agricultural production regions are impacted by economic and technological forces that increase the size of agricultural operations and the carrying capacity of the land. This has in turn created a global system of agriculture and the interdependence of regions of agricultural consumption and production.