Working the land to grow food was an entirely new way of life for prehistoric humans. It turned them from nomads into farmers—and created settlements with permanent buildings, larger societies, and the potential to develop more elaborate technology and culture.
The earliest humans mostly lived in small nomadic bands and went wherever food was plentiful. They tracked the migrations of large animals as they hunted for meat, just as they followed the seasonal bounties of fruit and seeds. They built—and rebuilt—simple camps, carrying a few lightweight belongings with them.
This hunter-gatherer existence supported humans through the last ice age, but about 12,000 years ago, a rise in Earth’s temperature opened up a world of alternative possibilities. One species of human—Homo sapiens— successfully emerged into this warmer world. By this time, these modern humans had spread far beyond their African ancestral home into Asia, Australasia, and America. And independently, all over the world, they had begun creating permanent farming settlements.
Settling down
Permanent camps with stronger houses made sense in places where the land was especially fertile—such as on floodplains of rivers. Settlers could support more hungry mouths by hunting, fishing,and gathering plant food around a local foraging ground that was rich in resources. This was just a small step from farming, as it was more convenient to nurture or transplant food plants closer to home or plant their seeds and tubers (some recent evidence suggests people had started to do this as early as
23,000 years ago)—while the most amenable wild animals were confined to pens. These first farms produced more food to feed more people, so settlements could grow bigger and even produce a surplus to help with leaner times. Valuable food stores—defended from competing camps—became another reason to stay in one place.
Domestication
By about 10,000 bce, agriculture had emerged in Eurasia, New Guinea, and America, with farmers relying on local plants and animals as favored sources of food. They learned that some species were more useful than others, and so these became staple parts of their diets.
In the fertile floodplains of Mesopotamia (modern Iraq), local wild wheat and barley became the cereal grains of choice, while goats and sheep provided meat. East Asia’s main cereal grain was rice, and in Central America, farmers cultivated corn. In all cases, the first farmers selected the most manageable and high-yielding plants and animals.Over time and generations, their choices would change the traits of wild species, as crops and livestock passed on their characteristics to form the domesticated varieties we use today. With domestication, settlements became increasingly reliant on the limited kinds of plants and animals that provided the bulk of their food. As a result, although food was plentiful, it sometimes lacked dietary balance. More time was needed to work the land, and livestock could be lost during droughts. People’s health was often poor, as crowded settlements encouraged the spread of infectious disease among humans, as well as their livestock.
Ultimately, agriculture’s success, or otherwise, was a trade-off between these risks and benefits. In some parts of the world—such as the Australian interior—conditions favored more traditional nomadic lifestyles, and here humans largely remained hunter-gatherers. As farmers gained a better understanding of the needs of their crops and livestock, they developed ways of overcoming risks and increasing productivity. They learned how to use animal dung as fertilizer or to irrigate the land by diverting rivers—curtailing effects of seasonal drought. In Egypt, for example, the waters of the Nile were used for large-scale irrigation of farmland, helping to lengthen growing seasons.
Over time, food productivity became material wealth: more food not only fed more people but facilitated trade, too. At the same time, larger settlements could support people with different skills, such as craftsmen and merchants. It meant that the agricultural revolution would have far reaching consequences for the history of humankind— including the emergence of industrial towns and cities.
When hunter-gatherers abandoned their nomadic life and became the first farmers, they were doing more than feeding their families. They were kick-starting an agricultural revolution that would have enormous implications for the future of humanity.
Evidence for agriculture’s origins comes from archaeology and from DNA of crops or livestock and their wild counterparts. No one knows exactly why people started to work the land. Perhaps they transplanted wild crops closer to home for convenience or saw the potential of germinating seeds. Whatever happened, as climates warmed in the wake of the Ice Age and populations swelled, people around the world—entirely independently—became tied to farming. It brought a stable source of nourishment and sometimes, when yields were good, a surplus to sustain people through leaner times. Tending crops or corralling livestock demanded that communities stayed in one place long enough to reap the harvest. Other reasons for staying in one location would have been that the new farming tools were too heavy to carry from place to place and any food surplus had to be stored. While agrarian settlements grew to become the seeds of civilization, their communities spread, taking their skills, plants, and livestock with them.
DOMESTICATION REVOLUTION - WILD SPECIES TO CROPS AND LIVESTOCK
The crops and livestock that humankind uses today descended from wild species that had rather different characteristics. Farmers chose to breed from individuals that served them best, such as by selecting ones that provided better yields or were more easily managed. This so-called artificial selection, applied over many generations and sometimes across centuries, gave rise to domesticated forms of plants and animals.
1. DOMESTICATION OF CROPS IN ASIA: (CHINA 11,000–3000 bce)
Rice became the staple cereal grain crop in river valleys in China. Farmers chose the best glutinous rice grains to grow more plants, so rice grains got bigger. This human-driven change had already transformed wild wheat in Mesopotamia, where harvesting by sickles had, by chance, favored non-shattering seed heads. But selection of rice grains in Asia probably happened through more conscious effort.
2. AGRICULTURE IN THE WET TROPICS:(NEW GUINEA 10,000–4000 bce)
Covered with rain forest, the tropical island of New Guinea offered a completely different mix of food plants. Instead of cereal grains, people grew fruit and root crops—notably banana and taro, the latter of which has both edible roots and leaves and is still a local food staple. But farming here was only part of the local economy; the region remains today the only primary center of agriculture that has not contributed domesticated species to the rest of the world.
3. EARLIEST EVIDENCE OF AGRICULTURE: (MESOPOTAMIA 12,000–4000 bce)
It is no coincidence that some of the earliest crops were grown on the nutrient-rich floodplain between the Tigris and Euphrates Rivers of modern-day Iraq. Here in ancient Mesopotamia (meaning “between rivers”), wheat was domesticated around 11,000 bce. This region was part of a so-called “Fertile Crescent” that stretched westward as far as the Levant and became key to the global agricultural revolution.
4. LIVESTOCK BEFORE CROPS: (AFRICA 9000–2000 bce)
In some parts of the world, animals were domesticated before crops. In Africa, cattle were being used as early as 9000 bce, but local cereal grains, such as millet and sorghum, were not domesticated until thousands of years after that. Agriculture began in the Sahara; due to increased rainfall after the Ice Age, the area was then covered by grasslands, lakes, and marshes. As the region dried, agriculture spread southward.
In "History of World Map by Map",lead senior editor Rob Houston, DK Penguin Random House, London & New York, 2018, excerpts pp.22-25. Digitized, adapted and illustrated to be posted by Leopoldo Costa.