Domestication today is a self-conscious enterprise of advanced science and global-scale effort, an applied research endeavor comprised of thousands of highly trained and well-supported international specialists. Major research centers like the International Potato Center in Lima, Peru support ongoing efforts to further the domestication of useful species; seed banks have been established in many countries to insure the future diversity of the world’s key domesticated plants . The prehistoric beginnings of agriculture though were quite different. The modern world that funds and depends on this continuing process of domestication is, in fact, a creation of the first early humans that pursued, consumed and, in doing so, modified the wild ancestors of the staples that we consider to be important today— wheat, millet, sweet potato, rice, and domesticated animals such as camelids, pigs, sheep, goats, and cows—to name a few. At present it appears as if at least six independent regions of the world were the primary loci of domestication and emergent agriculture: the Near East; sub-Saharan Africa; China/Southeast Asia; Eastern North America; Mesoamerica; and South America , plant raspberry in container roughly in the time period from thirteen thousand to eight thousand years ago . The archaeological record suggests that this transformation took place in societies that look much like modern day hunter-gatherers .
Many of the early domesticates were transmitted broadly through preexisting exchange networks , stimulating the migration of agriculturalists into the territories of hunter-gatherers, who were in turn ultimately replaced or subsumed into agricultural economies . Foraging peoples initiated domestication. They did so through the mundane and necessary daily tasks of locating, harvesting, processing, and consuming foodstuffs. The Mass from the 1928 Book of Common Prayer speaks eloquently of “these thy gifts and creatures of bread and wine . . .” In less poetic non-ecclesiastical terms, but with no less awe at the high importance and, well, the simple gastronomic pleasure of domesticates in our lives, this volume attempts to advance our understanding of why and how this happened. In particular, we hope to demonstrate the utility of a branch of evolutionary ecology, human behavioral ecology.The reasons for inconsistencies in the treatment of terminology are several and tenacious because they are ultimately rooted in the nature of the problem itself. These include, but are not necessarily limited to the following: research on domestication and agricultural origins is inherently a multidisciplinary activity, and as such, a wide-ranging set of specialists have worked on the problem, each emphasizing definitions that are somewhat parochial; historical change in each research tradition of archaeology, botany, and genetics has resulted in a range of definitions that may have been suitable at the time they were conceived but now add to the confusion; rapidly expanding empirical knowledge and the characterization of local developmental sequences results in specialized language that does not transfer well to other regions where similar transformations occurred; agricultural origins are an inherently evolutionary question and, as in any system of descent with modification, categorical or taxonomic distinctions have fuzzy and, for different cases, unevenly and perhaps differently demarcated boundaries; and, food production and agriculture have an impact on multiple features of human societies—e.g., economic, political, social, and ideological, any one of which might be featured in definitions.
Like earlier attempts, our definitions reflect limitations of our knowledge and approach. Hunting and gathering entails obtaining daily sustenance through the collection or pursuit of wild foods; wild foods in turn being species whose reproduction and subsistence are not directly managed by humans. Data from around the world indicate that prior to approximately thirteen thousand years ago, all people known archaeologically relied upon hunting and gathering wild foods. Hunting and gathering populations expanded into a broad range of habitats during the Terminal Pleistocene and Early Holocene when foraging strategies diversified , in part due to the extinction of previously targeted, large-game species, but also because of the broad array of resource alternatives afforded by warmer Holocene climates . Hunting and gathering societies have persisted in various parts of the world , but starting after about 13,000 BP most foragers evolved into or were subsumed or replaced by groups practicing mixed foraging and cultivation strategies and, ultimately, agriculture . On the other end of a mixed spectrum of subsistence strategies is agriculture. We define agriculture as the near total reliance upon domesticated plants or animals; domesticates being varieties or species whose phenotype is a product of artificial selection by humans, and whose reproduction and subsistence are managed directly by people. For plants, such management almost always involves an investment in seed selection; clearing, systematic soil tillage, terracing to prepare fields, crop maintenance, weeding, fertilization, and other crop maintenance; and, development of infrastructure and facilities from irrigation canals to processing facilities and storage bins. Parallel efforts are entailed in animal husbandry. Even societies practicing the most intensive forms of agriculture may engage in incidental hunting and gathering of wild foods, depending upon their availability or desirability . Dense populations and centralized state-level societies like our own depend upon increasingly complex systems of agriculture involving modification to soil texture, structure and fertility and sometimes resulting in severe environmental degradation, one of the great challenges of our day .
Domesticates are new plant or animal varieties or species created from existing wild species through incidental or active selection by humans . Typically selection leads to biological characteristics that are advantageous to humans; larger seeds, thinner seed coats, greater docility, smaller size animals. Because humans intervene in the natural life cycle of these plants and animals, many domesticates loose their ability to survive without human management. This outcome is not surprising since it is well known that foragers alter the landscape that they inhabit by burning, transferring plants and animals between habitats, and occasionally interjecting themselves into other species’ life cycles . Some plant species were better suited to domestication than others due to their ability to do well in the artificial environments created by humans . In some instances, the biological changes may have begun incidentally as a co-evolutionary by-product of human exploitation. In other cases domestication may have occurred under conditions of repeated cultivation and harvest . Cultivation is the tending of plants, wild or domesticated; husbandry is the parallel term for animal species. Use of the term cultivation specifically acknowledges the possibility that humans tended wild plants for significant time periods before we would classify them as domesticates based on observable genetic alterations . We reserve the term cultigen for domesticated plants under these same conditions. A variety of stable subsistence economies, extant, historic, and prehistoric, draw upon elements of hunter-gatherer and agricultural modes of production. These are difficult to characterize in existing terminologies except as “mixed” economies, engaged in what Smith has characterized as low-level food production. They typically depend significantly on hunting and gathering while to varying degrees using cultigens or keeping domesticated animals. Horticulture, the small-scale planting of domesticated species in house gardens or the use of swidden plots, combined with routine hunting and gathering of wild foods for a significant part of the diet, would be considered a form of low level food production. Contemporary casual farming by the Mikea hunter-gatherers of Madagascar would be an example of this practice . The boundary between low-level food production systems and agriculture is inherently fuzzy. We believe the term agriculture is merited when foraging recedes to an episodic, infrequent or recreational activity, regular provisioning using domesticates takes over daily subsistence, plastic seedling pots while agricultural work and animal husbandry come to dominate the activity schedules of adults. Although numeric boundaries are somewhat arbitrary and unsatisfactory, agriculture implies that approximately 75% of foodstuffs are acquired from domesticated sources. Although few contemporary societies engage in low-level food production, the archaeological record suggests that mixed foraging and cultivation/husbandry strategies were common and often stable, in the sense that they were practiced by people for thousands of years before they developed a full commitment and reliance upon agriculture .Speculation about the origins of food production is probably as old as the first encounter between peoples who recognized that they differed appreciably in their dependence upon domesticated plants or animals. Longstanding traditions in western thought have seen foragers as scarcely removed from animal nature, thus, as societies, simple and primitive, living without the many accoutrements and means of control over nature that we associate with agriculture and industrial culture .
Agriculture as an advance was instantly understandable. Hobbes’s famous sentiment that hunting and gathering was a life “solitary, poor, nasty, brutish, and short” is widely cited, but his views were generally shared in the nineteenth century, for instance by the novelist Charles Dickens . We today dismiss this kind of progressive evolutionism as simple-minded ethnocentrism. Foragers may not be the “original affluent society” claimed by Sahlins , but most foraging societies elude the generalizations implied in each of Hobbes’s five famous adjectives. We cannot so easily dismiss questioning just what distinguishes foragers from food producers and how humans evolve, in either direction, from one to the other of these subsistence forms or maintain a mixture of the two for long periods of time. European scholarly tradition, informed by increasingly reliable ethnography and archaeology, has a long engagement with agricultural origins . We highlight three of the most popular forces employed by archaeologists to explain the origins of agriculture: demographic pressure, environmental change, and socioeconomic competition. Demographic pressure and environmental change are exogenous forces and socioeconomic competition is endogenous. None in and of itself satisfactorily explains the origins of agriculture; each was probably an important element of the process, whatever the strength of its causal role. One of the virtues of HBE is its ability to integrate multiple variables like these, with an emphasis on behavioral responses to changing socio-ecological conditions.Population-resource imbalance caused by demographic pressure is one of several univariate explanations for the origins of agriculture . In the best known formulation of this idea, Mark Cohen argued that worldwide population growth explained why hunter-gatherers living in different locations independently turned to agriculture at the end of the Pleistocene. The argument was based on the premise that the adoption of agriculture resulted in a net increase in workload and a decrease in food diversity and sufficiency, and therefore an overall reduction in the quality of life, a situation that any rationally minded hunter gatherer would not enter into freely. Cohen argued that as hunter-gatherers exceeded environmental carrying capacity, food shortages pushed them to experiment with plants and animals and, ultimately, with agriculture. Hunter gatherers over-filled salubrious habitats worldwide and were compelled to augment their subsistence with food production. Critics of this position were quick to point out that the archaeological record does not support the idea that environments worldwide were saturated with hunter-gatherer populations on the eve of agricultural development . Even localized populations in the primary centers of early domestication appear to be relatively small . Others have emphasized the difficulties of measuring population levels in the archaeological record or determining the overall population levels that could be sustained without significant amounts of environmental degradation and pressure for change . There have been attempts to better contextualize demographic change by melding it with ecological models, usually in relation to variations in climate . These models sometimes lack specificity about the form or degree of demographic pressure required to provoke subsistence change, and they seldom explain why hunter-gatherer populations grew more rapidly and stimulated domestication and agricultural development in certain parts of the world and not others . One response to the early overemphasis on demography has been to heavily discount its importance in the process of domestication and agricultural development . This is unfortunate because foragers clearly have dynamic relationships with their living resources and this in turn has population level effects . Even small hunter-gatherer populations alter the distribution and availability of harvested plant and animal species . Sometimes this results in decreased availability or resource depression; in other instances, it may result in increased resource abundance. The effects that hunter-gatherers have on the density, distribution, and productivity of resources is well documented in California and Australia . Environmental change independent of humans is ubiquitous and can also affect the distribution and availability of important species. Economic decisions by prehistoric foragers to experiment with and ultimately manage certain species of plants and animals occurred within this dynamic context of demographic change and varying plant and animal densities.V. Gordon Childe was one of the first, and certainly the most notable, archaeologists to explicitly hypothesize that changes in climate at the end of the Pleistocene stimulated the transition to agriculture .