The Agricultural Revolutions

You’ll be able to

Trace the First, Second, and Green (Third) agricultural revolutions
Distinguish subsistence from commercial agriculture by intensity and purpose
Evaluate the benefits and costs of the Green Revolution

Three revolutions in how we farm

Farming has been transformed three times. The First (Neolithic) Agricultural Revolution, ~12,000 years ago, was the domestication of plants and animals, which let humans settle in permanent villages. The Second Agricultural Revolution, alongside the Industrial Revolution (1700s–1800s), used new tools, crop rotation, and mechanization to raise yields and free labor for city factories. The Green Revolution (Third), from the mid-20th century, spread high-yield seed varieties, chemical fertilizers, pesticides, and irrigation to the developing world, dramatically increasing output — Norman Borlaug’s wheat in Mexico and India, IR8 rice in Asia.

Subsistence vs. commercial agriculture

Two purposes divide the world’s farms. Subsistence agriculture grows food chiefly for the farm family’s own consumption; it dominates in less-developed regions and includes shifting cultivation (slash-and-burn), pastoral nomadism, and intensive subsistence rice farming. Commercial agriculture produces for sale in a market, dominates developed regions, relies on machinery and few farmers, and includes mixed crop-and-livestock, dairy, grain, and plantation farming. Intensity also varies: intensive agriculture applies much labor or capital to a small area, extensive agriculture spreads little input over large areas (ranching, nomadism).

The Green Revolution’s double edge

The Green Revolution saved perhaps a billion people from famine and made countries like India food self-sufficient — but at a cost. It requires expensive inputs (seeds, fertilizer, fuel, irrigation) that poorer farmers cannot always afford, widening inequality; heavy chemical use degrades soil and water; irrigation drains aquifers; and reliance on a few high-yield varieties reduces biodiversity, raising vulnerability to pests. Its benefits also skipped much of Sub-Saharan Africa, where soils, infrastructure, and crops did not fit the model.

Worked example

A farmer in the U.S. Midwest grows thousands of acres of corn with GPS-guided machinery, hires almost no labor, and sells the entire harvest to a grain company. Classify this operation by purpose and by intensity, and justify each.

1.The corn is grown to be sold on the market, not eaten by the farm family, so the purpose is commercial agriculture.
2.Vast acreage is worked with machines and very little labor per acre — inputs are spread thinly over a large area.
3.Low labor and capital input per unit of land marks this as extensive agriculture.
4.This combination — large-scale, mechanized, market-oriented grain farming — is typical of commercial agriculture in developed regions.

Answer: By purpose it is commercial agriculture, since the entire crop is sold. By intensity it is extensive, because minimal labor is applied per acre across a huge area with heavy mechanization — the hallmark of developed-world grain farming.

Checkpoint

The domestication of plants and animals that first allowed humans to shift from hunting and gathering to settled village life is known as the:

Tip

Two independent axes describe any farm. Purpose: subsistence (grown to eat) vs. commercial (grown to sell). Intensity: intensive (much labor/capital on little land) vs. extensive (little input over much land). A question may ask about either, so name both when in doubt.

Checkpoint

Which is a commonly cited negative consequence of the Green Revolution?

Answer the 2 checkpoints as you read.