Before the invention of agriculture, people obtained food from hunting wild animals, fishing, and gathering fruits, nuts and roots. Having to travel in small groups to obtain food, people led a nomadic existence. This remained the only mode of subsistence until the end of the Mesolithic period, some 12,000-10,000 years ago. Then, agriculture gradually replaced the hunting and gathering system, constituting the spread of the Neolithic revolution. Even today, some isolated groups survive as they did before agriculture developed. They can be found in some remote areas such as in Amazonia, Congo, Namibia, Botswana, Tanzania, New Guinea, and the Arctic latitude, where hunting dominates life (Figures 10.1, 10.2, and 10.3).
The term agriculture refers to the cultivation of crops and the raising of livestock for both sustenance and economic gain. The origin of agriculture goes back to prehistoric time, starting when humans domesticated plants and animals. The domestication of plants and animals as the origin of agriculture was a pivotal transition in human history, which occurred several times independently. Agriculture originated and spread in different regions (hearths) of the world, including the Middle East, Southwest Asia, Mesoamerica and the Andes, Northeastern India, North China, and East Africa, beginning as early as 12,000 – 10,000 years ago. People became sedentary, living in their villages, where new types of social, cultural, political, and economic relationships were created. This period of momentous innovations is known as the First Agricultural Revolution.