Prehistoric exchange has long been central in anthropological and economic models of socio-political change. Exchange has been discussed by social theorists, anthropologists and archaeologists the debating the ultimate causes of socio-political inequality that emerged independently during the Holocene in different regions of the world. In the course of the last 12,000 years, archaeological evidence documents a change from a worldwide of hunting and gathering groups with relatively egalitarian, village-level social organization to, in a few places world-wide, in-situ development of state-level society with large settlements, greater concentration of wealth, and hierarchical economic and political organizations. While anthropological models accounting for political and economic change have been refined over the past century, evidence of exchange has consistently served as a material indicator of regional interaction and differential access to exotic goods within a community.
Regional exchange is of particular utility to anthropological archaeology because it is a material phenomenon that occurs at the intersection of social relationships, resource procurement, and individual or community differentiation. However, exchange has been attributed with great causal significance in the past and, while it provides evidence of particular utility to anthropologists and archaeologists, it is important to not ascribe excessive significance to exchange in human affairs. For example, to V. Gordon Childe (1936) long distance trade was a prime mover that had direct social evolutionary consequences. Engaging in trade had derived benefits that can affect the balance of power between competing polities and stimulate larger forms of organization.
In the 1970s, Rathje (1971;1972) proposed that it was the lowland Maya need for "essentials" like obsidian, salt, and grinding stones that propelled them to seek external sources for these scarce goods, initiating long-distance relationships. Those who control access to scarce materials accrued benefits from their position in the trade network, he argued, and hierarchies emerged from the differential access to these required, or desired, trade goods. Virtually all of Rathje's postulates have since been disproved, but some variant of the theme first articulated in Rathje's exchange model underlies many contemporary investigations of ancient trade (Clark 2003: 33-34).
In the multilinear evolutionary framework of Johnson and Earle (1987), trade is part of an array of processes that are relevant to socio-political development, but trade does not become a dominant process until the formation of the Nation-State.
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Economic Processes in Political Evolution |
|||
|
Local Group |
Regional Chiefdom |
Early State |
Nation-state |
|
WARFARE |
warfare |
warfare |
warfare |
|
risk management |
RISK MANAGEMENT |
(risk management) |
(risk management) |
|
technology |
technology |
TECHNOLOGY |
(technology) |
|
trade |
trade |
trade |
TRADE |
Table 2-2. Economic processes in political evolution (Johnson and Earle 1987: 304) where capitalized words indicates a dominance of that process, parenthesis indicate important secondary processes.
The approach taken here is that all human groups engage in exchange in some form and it therefore serves as a consistent index of regional relationships through time. Furthermore some trade items, such as obsidian, appear to have been part of a suite of features that, at particular times and socio-political contexts, serve to differentiate individuals or groups from the rest of their community for purposes relating to political strategy. While exchange is not a prime mover for socio-political change, transfer between peoples and groups in different forms provides a vehicle for social differentiation and a materialization of geographical relationships that are closely linked to socio-political organization. Thus, while one may see exchange occurring over the long term, it is not a prime-mover but it is changes in evidence of production, transfer, and consumption of non-local goods that inform theoretical models of prehistoric change.
Forty years ago, advances in technical analysis in archaeology, in particular geochemical sourcing, initiated several decades of research into exchange by archaeologists. Following the dominant theoretical approaches of the time, adaptationalist or managerial models held that socio-political change was stimulated by factors that impacted the entire cultural system. Such changes could be stimulated by a combination of factors, including external pressures and internal pressures. External pressures include resource stress, drought, and warfare. Internal pressures include greater efficiency in organization despite larger population levels, irrigation, and organizational complexity due to circumscription.
More recent theoretical approaches focus on social and political strategies prioritize the active role of individuals in the process of political change. The role of commodity exchange in the onset and dynamics of socio-political complexity connects the exchange behavior documented by anthropologists with the long term changes that underlie the archaeological evidence of exchange in prehistory. Leveling mechanisms among hunter-gatherers promote intergroup sharing and are especially prominent when resource predictability is low. With greater resource predictability, and especially when resources are intensifiable, these leveling mechanisms often begin to break down and social differentiation is observed.
Exchange is thought to have been one of a number of interacting behaviors by "aggrandizing" individuals that had the indirect result of institutionalizing social inequality (Clark and Blake 1994;Flannery 1972;Hayden 1995;Hayden 1998;Upham 1990). What were the socio-political contexts that permitted individuals to differentiate themselves, and how did individuals pursuing their interests result in the long-term changes observed archaeologically?
While early social hierarchy emerged from the so-called egalitarian contexts of small-scale societies, Wiessner (2002: 233) observes that "hierarchy characterizes the societies of our closest non-human primate ancestors and seems to be deeply rooted in human behavior" and social hierarchy can therefore be considered a "reemergence" of hierarchy. Egalitarianism is not the "tabula rasa for human affairs on which aggrandizers impress their designs" (Wiessner 2002: 234); rather, it is the result of coalitions and complex institutions of weaker individuals in society that curbs the ambitions of the strong and results in egalitarian structures that were as complex and varied as hierarchical power structures. Wiessner argues that cooperative behavior, such as elaborate exchange relationships, in egalitarian institutions fostered ideologies of coalition building and cooperation in kinship-based networks that extended far beyond local groups. While the egalitarian ethos constrained the competitive activities of aggrandizers, these institutions also provided powerful tools to the cooperative structure that could be used to the advantage of aggrandizers. Exchange has particular significance in agency models that strive to explain how the activities of aggrandizers can result in institutionalized inequalities because exchange can contribute to an understanding of the relationship between structure and agency at this juncture.
Aggrandizers had to work within powerful institutional boundaries that already existed in egalitarian societies in order to forward their interests. The changing nature of exchange, embedded within shifting institutional contexts, complements the emphasis on alienable commodities (Appadurai 1986, see Section 2.2.2). Aggrandizing individuals operate within institutional contexts, indeed their vehicle to promotion is social recognition, yet the ability to organize resources to obtain lower costs for particular items benefits aggrandizers and their supporters. Exchange is a universal feature of human societies, and studies that document the diversity of forms that exchange takes in contexts of early social ranking can shed light on the specific strategies used by aggrandizers that resulted in institutionalized inequality (Clark and Blake 1994).
Beginning with settlement pattern studies explored by Julian Steward, processual archaeologists often assume regional perspectives that emphasized social and organizational processes (Willey and Sabloff 1974). Building on Polanyi's observation that fundamental aspects of human institutions are economic, archaeologists understood that documenting the regional distributions of artifacts resulting from prehistoric mobility or exchange could contribute to reconstructing past societies. Archaeologists can use direct evidence from the production and consumption of archaeological materials and inference about the likelihood and form of prehistoric exchange to point to the institutional contexts of the ancient economy.
In Polanyi's (1957) seminal article outlining the substantive approach, "The economy as an instituted process," the economy is characterized in terms of two linked properties. First, there is the material process by which items are produced, circulated, and consumed; second, there is the economic form organized around socio-political relationships that arranges interactions diachronically and spatially. In this context, institutions serve as rules and obligations connecting human organizations around the process of producing and circulating goods. The implication is that an archaeological study of variation in prehistoric economies requires that archaeologists can document differences in the institutions that structured past economies.
Many contemporary theoretical approaches downplay the importance of structural analyses in favor of agent-based models, however anthropologists using New Institutional Economics (North 1990) are emphasizing the interdependence of institutions and economics and the implications for activities of individuals (Acheson 2002;Ensminger 2002). Douglass North (1990: 3) defines institutions as "the rules of the game in a society or, more formally, the humanly devised constraints that shape human interaction". This view considers how institutions developed from the decisions of individuals over long periods of time, affecting transaction costs through the benefits of coordinated activity. "Based on the advantages of lower transaction costs in commodity flows, [these anthropologists] argue that political and social institutions developed to regulate commodity flows, maintain regional peace, and guarantee contracts" (Earle 2002: 82). In this perspective, institutional complexity developed as rules to govern the economizing nature of individuals, and the emergence of such institutions should be correlated with increasing quantities of commodity exchange in prehistory. The perspective that argues that volume of exchange should correlate with increased social complexity has roots in theories of progressive evolution (Childe 1936), adaptionalist views (Steward 1955), and the managerial role of chiefs (Service 1962).
However, a positive correlation between evolving institutional complexity and a uniform increase in volume or variety of exchange in prehistory is not supported empirically (Brumfiel 1980;Hughes 1994;Kirch 1991). That is, contrary to the evolutionary expectations of some theorists, the volume or variety of goods transferred does not necessarily reflect the political or institutional complexity in a given society. Perhaps some of this inconsistency is the result of elite control of the circulation of commodities as proposed by Appadurai (1986: 38). Earle (1994: 420-421) observes that on the whole, the archaeological evidence is characterized by a great deal of variability in the types of goods exchanged, the volume of exchange, and the social contexts of exchange. In order to address this variability in an evolutionary framework, Earle suggests that exchange should be considered in terms of two categories, the subsistence economy and the political economy[1](Johnson and Earle 2000), with exchange taking different forms in each category of the economy. The exchange in these two forms of economy correspond largely to the distinction discussed earlier between ordinary goods and prestige goods where, according to Earle, political strategy is advanced by elites by, among other things, the manipulation of exchange relationships.
In a non-evolutionist application of New Institutional Economics in anthropology, Wiessner (2002: 235) differs from North in arguing that transaction costs for exchange are actually high in small-scale societies due to the close relationship between social and economic transactions; there is less neutral space for "unembedded" economic behavior with their associated overhead costs. In such contexts egalitarian institutions developed to foster trust and make interactions more predictable.
In non-market economies in which kin-based exchange systems play an important role in reducing risk (Wiessner 1982;Wiessner 1996) the goal of exchange is to be covered in times of need. In this context, the social and the economic are closely intertwined (Mauss 1925) and it is undesirable for returns to be stipulated as to time, quantity, or quality (Sahlins 1972). The most valuable information in such exchanges is the details of the partner - what he or she has to offer and will offer over the long run (Wiessner 2002: 235).
Elaborate institutions regulating behavior are not new, argues Wiessner, but if there is a weakening in the egalitarian prohibition against the accumulation of wealth or power the "alchemy of ambition" (Wiessner 2002: 234) drives a few individuals to seek preferential access to resources. In contexts of regional packing and circumscription it is argued that hierarchies emerge (Brown 1985;Johnson 1982) that are perhaps founded on the control of labor and surpluses, and instituted through ritual (Aldenderfer 1993;Hayden 1995)
Materialist perspectives hold that economic gains are used to bring about changes in the social order, and that these changes are then legitimized and perpetuated through ideology. These economic gains are generally achieved through intensification of production and through finance organized by ambitious individuals (Boone 1992;Earle 1997;Hayden 1995). Clark and Blake (1994: 17), building on practice theory (Bourdieu 1977;Giddens 1979), describe a model whereby institutionalized inequality is the unintended outcome of political actors competing for prestige by using strategies that match the self-interests of their supporters. Ultimately, these strategies may develop into redistributive institutions that appear to build on the social-leveling mechanisms described by Wiessner (1996), but operate on a larger scale and result in political advantage for redistributing leaders and their allies. In other words, it is institutions themselves that form the basis for leveling mechanisms, and it is institutions that are transformed into vehicles that serve to, in part, legitimize social inequalities.
An important temporal component to exchange is connected to institutions as well because transactions involve anticipation and scheduling. As Colin Danby (2002) argues, most transactions in neoclassical economic analyses in anthropology are considered as synchronic "spot transactions" of commodities, while long term interpersonal relationships enter the domain of gifts in a gifts: commodities dichotomy. The temporality of reciprocation is a means by which economic transactions are embedded inside of social calendars, but various socially-mediated methods of extending credit are well-established and probably an ancient manner of precipitating exchange in market-based transfers as well.
The domestication of cargo-bearing animals contributed several important elements that transformed the nature of regional exchange relationships. First, there are some cross-cultural commonalities in the structure of contemporary societies practicing pastoralism, and it is probable that these factors had some role in prehistoric pastoral societies as well. Second, cargo-bearing animals transform the costs of transport and, consequently, the nature of long-distance interaction. Finally, the structure of wealth in animal herds conveys particular scalar advantages to powerful kin-groups that possess large herds. These factors condition long-term transformations such as sedentism, the nature of food production, and the institutionalization of social inequalities. These issues will be explored in three sections: household level articulation with agriculturalists, wealth accumulation among herders that is limited by risk and pasture, and caravans and the organization of pastoral labor.
An important structuring principle to pastoralist exchange is that herding systems are not economically independent because humans must consume a sufficient diversity of major food groups for nutritional reasons; a condition known as non-autarkic (Khazanov 1984;Nielsen 2000). Depending on available wild plants, herders may acquire a portion of their non-animal products from gathering activities but the more common solutions involve a mixed agro-pastoral strategy or articulation with agriculturalists. Furthermore, herders with animals capable of bearing loads are the natural agents for facilitating this articulation with agriculturalists (Browman 1990;Flores Ochoa 1968). Thus, exchange relations are a basic necessity for dedicated herders. For herders with cargo animals, the transport of exchange goods in some capacity was likely a regular feature of pastoral household economies, and to become more common and less laborious in terms of quantity of goods exchanged due to assistance of cargo animals. As pastoralist households are not autarkic, due to the need for non-animal foods on a regular basis, households usually have cargo animals as part of their herd and relatively brisk exchange networks are likely to develop between households without the need for elites, administrative oversight or investment from super-family organization.
Inequalities are evident in most pastoral societies as owners with large herds are better able to maximize by grazing all available lands when conditions allow and hiring additional help with herding tasks like shearing and butchering. Furthermore, large herds can reproduce more quickly, are better able to survive hardship, and better maintain a minimum herd size threshold for viability. Nevertheless, pastoral wealth is widely recognized as unstable due to the overall vulnerability to drought, disease, parasites, predators, theft, and accidents that can cause declines of over 50% in a given year (Khazanov 1984: 156;Kuznar 1995;Nielsen 2000: 42;Salzman 1999). Herders mitigate this risk by diversifying production, maintaining extensive exchange networks, holding access to grazing land in common, and utilizing other institutional means of risk reduction, such as the redistribution mechanism of suñay among Andean pastoralists (Flannery, et al. 1989).
A significant pastoral institution that appears to function as a leveling mechanism is the corporate ownership of pasture. While herds are typically held by individuals or kin-groups, herding is spatially extensive rather than intensive, and access to pasture in herding societies almost universally requires community negotiation (Ingold 1980;Khazanov 1984;Nielsen 2000: 46-51). Among pastoral societies that do not store fodder the carrying capacity of the land, and therefore the intensifiability of production, is limited by the season with the lowest productivity (Nielsen 2000: 43). Finally, in some regions of the world, such as the Andes, modern herds are bilaterally inherited which serves to prevent accumulation in specific descent groups (Lambert 1977;Webster 1973: 123). Thus, herding does not organizationally contain the seeds for social inequality, but intensified pastoral wealth in the form of very large herds has been documented as one principal form of investment in ethnohistorically known hierarchical societies in herding regions.
Pastoralist societies that organize into seasonal trade caravans share structural characteristics; some of these characteristics tend towards promoting social inequalities and others that counter-act the tendency (Browman 1990). The organizing of a trade caravan is often simplified among dedicated pastoralists because pastoralism is relatively efficient in the use of labor, and the herding and caravanning schedules can be prioritized (Nielsen 2000: 44-45). A single herder can monitor hundreds of animals on a typical, uneventful day of pasturing without a great deal of effort, and as physical labor is low as compared with agricultural tasks, children and the elderly often contribute and broaden the herding labor pool. As a consequence, during caravan season the loss of several capable family members (usually adult men) to the caravan journey for weeks or months during a single year may not unduly hamper the productivity of a household of dedicated pastoralists.
As mentioned above, all pastoral households must acquire non-pastoral products through diversification or exchange, however the ability to organize a caravan inherently favors the wealthier herders for several reasons.
(1) Herders with large herds are more likely to have a sufficient number of hearty animals capable of enduring long journeys with cargo.
(2) Caravan animals provide the mechanism of transport. Therefore, for direct exchange consisting of spot transactions, pastoralists must initiate the trade opportunity by traveling to their trade partners with a sufficient surplus of goods to acquire goods in exchange.
(3) The rewards of such trade caravans accrue differentially, allowing those who regularly participate in such ventures to acquire access to non-pastoral resources, a more extensive social network and perhaps fictive kin among distant trade partners, and enhanced prestige among their community.
While some elements of dedicated herding societies favor differential accumulation of wealth in the form of large herds, diversification of the resource base, and extensive trade networks, the realities of high risk to pastoral wealth and low intensity of land use affect all herding households equally to the extent that they dedicate themselves to pastoralism. Thus, while redistributive mechanisms and corporate tenure of pasture serve to stabilize pastoral systems, the structure of herding systems also provides a few opportunities for strategic advantage to more opportunistic and aggrandizing elements of prehistoric society. In addition, despite the risk in herding systems the ownership of a large herd may directly confer prestige on pastoralists (Aldenderfer 2006;Hayden 1998;Kuznar 1995: 45), and inequalities in pastoral wealth can be channeled into more enduring and intensifiable avenues such as increased exchange (ultimately resulting in large trade caravans) or a mixed agro-pastoral strategy. As a pastoral economy with cargo transport capabilities first takes hold in a region, increased social differentiation may reflect a co-evolution between more extensive exchange relationships, greater sedentism, population increases, and larger population centers.