Humans relied on hunting and gathering for nearly two million years. Deceptively simple, hunting and gathering groups depended on an extensive knowledge of their local areas. Integral to their life was mobility, as survival revolved around linking food availability with seasonal changes and creatively exploiting every part of the environment. In general, hunting and gathering groups did not ‘live under the constant threat of starvation’ (Ponting: 1992) and their impact on the environment was limited (groups minimized damage to natural ecosystems as their overall population was small). Although the rate of technological development was slow, hunting and gathering groups greatly valued leisure time and often fine-tuned their strategies and techniques. About 10,000 years ago, humans began to abandon the stable, universal methods used to obtain food. Hunting and gathering groups moved from foraging to an ‘intensive system of food production’ (Ponting: 1992).
The adoption of agriculture was one of the most fundamental changes in human history. Altering the environment in order to ‘produce crops and provide pasture for animals’ (Ponting: 1992) resulted in increased productivity, specialization, and exchange. Agriculture ‘provided more food from a smaller area of land’ (Ponting: 1992) and the food surplus was used to support individuals not engaged in food production. Individuals were able to focus on producing specialized items for society, and these items were available for trade. Control of the food surplus was key, and societies established ‘mechanisms for its allocation’ (Ponting: 1992) through direct ownership or by the threat of force. Thus, the emergence of agriculture also led to socio-economic classes, government intervention, famine, and disease. Jack Harlan highlighted the paradox of agriculture in simple terms: ‘Why work harder, for food less nutritious and a supply more capricious?’ (Harlan: 1992).
Human motivations are difficult to decipher. Several theories have been posited to identify the causes of the rise of agriculture. Agriculture may have been a response to ‘opportunity rather than necessity’ (Weisdorf: 2005). Leisure represented a large proportion of the day for hunting and gathering groups, affording many groups the time to experiment with plants and animals. In the face of scarce resources, such as the extinction of large herding animals, hunting and gathering groups may have also turned to experimentation. Early humans may have ‘unintentionally manipulated their environment by selecting and re-planting’ (Weisdorf: 2005) certain species. Over time, these species required increased human assistance and humans relied more heavily on their survival for sustenance. Cultivation may have started as humans disposed of seeds in a common place, such as the cooking area, and returned years later to a plethora of wild grasses. The path to agriculture may have an evolutionary basis.
Global population growth may have forced hunting and gathering groups into less favorable environments. Foragers had to expand their subsistence. Because the quality of the plants and animals were less rich in their new ecosystems, displaced groups were driven to more intensive ways of exploitation, eventually leading to agriculture. As food production rose, more people were fed. The “ratchet effect” created pressure towards even more intensive ways of food procurement. But, the “chicken and egg” problem still exists; was agriculture a response to population pressure or did agriculture give rise to population pressure?
If agriculture was a response to global population growth, scarce resources should have eventually instigated a decrease in dietary intake. Studies of remains, however, ‘have failed to show nutritional stress immediately prior to plant domestication’ (Weisdorf: 2005). Demographic pressure did not produce a global food crisis, and it is unlikely the emergence of agriculture was merely a response to population pressure. Climatic changes, however, may have had serious implications on food availability. Researchers have identified a period of cold and dry environmental conditions (Younger Dryas), which decreased the yield of wild cereals. This downturn may have encouraged some hunting and gathering groups to cultivate.
Economics provides an additional lens with which we can understand the rise of agriculture. An externality arises when the action of one agent affects the welfare of another. There are negative externalities associated with hunting and gathering. Hunting and gathering groups have ‘an incentive to ignore certain costs of their activities’ (Weisdorf: 2005). Suppose a hunting and gathering group fires the undergrowth in order to open up the forest for safer hunting in their local area. Given dry conditions, the fire spreads to other areas, causing a massive decline in the region’s plant and animal species. The First Welfare Theorem of Economics suggests that ‘to obtain efficiency, price must equal social marginal cost in equilibrium’ (Katz and Rosen: 1998). That is, an agent must take into account all costs, including the external damage to other people, when determining output. The root cause of inefficiencies associated with externalities is the absence of defined property rights. Hunting and gathering groups ‘shared common property rights, which resulted in an over-utilization of resources’ (Weisdorf: 2005). Because agriculture required work on a specific plot of land, effective property rights were established. Secure property rights ‘provided an incentive to improve efficiency and productivity’ (Weisdorf: 2005) as owners were directly rewarded. Inherent differences in property rights tipped the scale in favor of agriculture and labor productivity eventually exceeded that of hunting and gathering.
The rise of agriculture is a puzzle with which we have scanty evidence. Agriculture sustains the vast majority of people on Earth. Given its scope, it is astonishing that there is no generally accepted model of its emergence.
A Green History of the World: The Environment and the Collapse of Great Civilizations. Clive Ponting; St. Martin’s Press, 1992.
Katz, Michael and Harvey Rosen. Microeconomics. 3rd Edition. McGraw-Hill. 1998.
Wadley, Greg and Angus Martin. The Origins of Agriculture – A Biological Perspective and a New Hypothesis. Journal of Australasian College of Nutritional and Environmental Medicine. Vol. 19, No. 1; April 2000. p. 3-12.
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