5.1 Introduction to Agriculture

What counts as agriculture

Agriculture is the deliberate modification of Earth's surface through cultivation of plants and raising of animals to obtain products for survival or economic gain. It includes subsistence agriculture (growing food mainly for the farmer's own family) and commercial agriculture (growing crops/livestock for sale in markets). Understanding this distinction is central to explaining global patterns of farming.

Origins and diffusion of agriculture

Agriculture began independently in several hearths (e.g., Fertile Crescent, Southeast/East Asia, Mesoamerica, Andes) roughly 10,000 years ago during the First Agricultural (Neolithic) Revolution. Domestication of plants and animals spread through diffusion, transforming hunter-gatherer societies into settled farming communities and enabling population growth, permanent settlements, and social specialization.

Agricultural revolutions changed land use

The Second Agricultural Revolution (linked to the Industrial Revolution) introduced mechanization, crop rotation, and improved yields, supporting urban growth. The Third Agricultural (Green) Revolution brought high-yield seeds, fertilizers, pesticides, and irrigation to increase food production, especially in developing countries — but raised concerns about environmental impact and unequal access to technology.

Key terms

Agriculture

Deliberate modification of Earth's surface through cultivating plants and raising animals for survival or profit.

Subsistence agriculture

Farming to feed one's own family rather than to sell for profit.

Commercial agriculture

Farming conducted primarily to sell products for profit in the market.

Agricultural hearth

A region where agriculture first originated and diffused outward, e.g., Fertile Crescent, Mesoamerica.

Green Revolution (Third Agricultural Revolution)

Mid-20th century shift using high-yield seeds, fertilizers, pesticides, and irrigation to boost food production, mainly in developing countries.

Try an AP-style question

Subsistence agriculture is…

1. farming mainly to feed one's family
2. farming for export
3. growing cash crops
4. large-scale mechanized farming