Is archaeology useful? Shannon Dawdy suggests that in the application of our knowledge to contemporary issues we find the utility in archaeological work. While I believe there are many ways archaeology is ‘useful’ beyond this application, I will pull that thread, illustrating the applications of archaeology to contemporary issues at the interface of society and environment. I then examine a few of Dawdy's concerns about the failings of archaeology.
Contemporary issues and the long-term perspective of archaeology
Archaeology brings time depth to an array of issues from migration and resettlement to climate change and environmental impacts of human actions. While study of the ancient past might seem irrelevant to contemporary concerns in light of globalization and rapid technological change, archaeology provides a long-term, historically contextualized view of numerous social–ecological transformations (e.g. Hegmon et al. 2008; Kirch 2005; Miller et al. 2009; Redman and Kinzig 2003; Van der Leeuw and Redman 2002). The long-term view does not provide predictions for future courses but it does provide an example, an experiment of sorts, by which we can come to understand processes and relationships better and critically examine assumptions.
While a variety of studies use archaeological research to contribute perspective to modern issues of the relationship between society, environment and climate (Briggs et al. 2006; Costanza et al. 2007; Crumley 1994; Kirch 2005; McIntosh, Tainter and McIntosh 2000; McGovern et al. 1988; Redman and Kinzig 2003; Redman et al. 2004; Tainter 2008; Van der Leeuw 1998), I wish to illustrate this approach with an example of the work we are doing at Arizona State University. Our study of long-term relationships between ecosystems and social systems in pre-Hispanic contexts examines key concepts employed by scholars and policy-makers in the Resilience Community (Anderies, Janssen and Ostrom 2004; Hegmon et al. 2008; Janssen and Anderies 2007; Nelson et al. 2006; Nelson et al., forthcoming; Spielmann et al., forthcoming). The concern of the Resilience Community is with the promotion of social and environmental policies that contribute to resilience – flexibility in responding to uncertain future conditions and avoiding catastrophic transformations (www.resalliance.org). So what drives our research are their issues, which we can examine over long time spans and then offer insights back to the resilience perspectives of that community. Our understanding of the archaeology is also enhanced with this collaboration.
We have focused on three issues that are common in the literature of the Resilience Community: the effect of rigidity on the scale of social–ecological change (Hegmon et al. 2008), the nature of the contribution of social and subsistence diversity to resilience (Nelson et al. 2006; Anderies, Nelson and Kinzig 2008), and how resilience to some conditions can create vulnerabilities to others – or the robustness–vulnerability trade-off (Janssen and Anderies 2007; Nelson et al., forthcoming). ‘Resilience’ refers to the ability of a system to absorb disturbances without losing its identity (Folke 2006) and its capacity to buffer change while maintaining essential structures and functions (e.g. Holling, Gunderson and Ludwig 2002). The concept originates in ecology (Holling 1973) but recently has been advanced by Resilience Alliance researchers and is finding its way into scientific and policy forums (Adger 2006; Folke 2006; Janssen and Ostrom 2006; Janssen et al. 2006; Young et al. 2006).
I illustrate our approach by describing the results of three studies by our research group of archaeologists, modellers and social and environmental scientists. We have used archaeological information from six regions in the south-western US and northern Mexico spanning AD 450 to 1600 – Mimbres, Mesa Verde Salinas, Zuni and Hohokam in the US south-west, and LaQuemada in the Malpaso Valley in Zacatecas, northern Mexico. Although the case studies are set in broadly similar arid environments and share a reliance on maize agriculture, the cases display varying degrees of investment in physical and social infrastructure and different historical patterns of change.
Rigidity
To address the effect of rigidity on the scale of social–ecological change, Hegmon led our research group in a cross-case comparison of three sequences – Hohokam, Mesa Verde and Mimbres in the US south-west – to ask why certain transformations were much more dramatic and fraught with human suffering than others (Hegmon et al. 2008). This question is as relevant today as it has been for centuries, even millennia. One answer, suggested by the Resilience Community, is a concept known as the ‘rigidity trap’, by which certain (often human-dominated) systems resist change and suppress innovation, eventually resulting in severe transformations. The results of our analysis supported this relationship; we looked at rigidity in three domains (kinds of integration, social power and material conformity) and found that the most severe transformations, with the greatest human suffering, were associated with the highest degrees of rigidity (Hegmon et al. 2008). We found that lack of flexibility, suppression of innovation, and resistance to change delayed transformation for some time, but not forever. While this ‘resilience’ concept informed archaeological interpretation, our work also informed the Resilience Community. One case in particular offered insights about why rigidity develops.
First, we suggested that rigidity develops with an absence of social options
The large irrigation system of the Hohokam region (the largest in pre-Hispanic North America), which was the focus of the rigidity of that system, was in place for nearly a millennium before the major institutional and demographic collapse of Classic-period Hohokam. Prior to the Classic, people engaged in a large regional network, which gave them contacts across southern Arizona (Abbott, Smith and Gallaga 2007). Faced with problems with river irrigation, the regional network offered options: they could draw on this network for goods and for relocation to other areas. But by the Classic period, that network had ended, and people probably had few contacts outside their immediate area, making decisions to leave more difficult. Their isolation contributed to rigidity.
Second, we suggested that rigidity develops with attachment to traditions
Henrich (2001) and Kohler, Van Buskirk and Ruscavage-Barz (2004), in their discussions of conformist transmission, suggested that conformity is self-perpetuating; once established, conformity begets further conformity. Janssen, Kohler and Scheffer (2003) also comment on attachment to tradition using the concept of the ‘sunk cost’ effect, which refers to resistance to abandoning a long-established course of action even when it is clearly disadvantageous. They argue that sunk costs may have contributed to the vulnerability and collapse of ancient societies. Both of these factors could have been in effect in Classic Hohokam society. People lived in the same places with the same technological and sociocultural traditions for generations. While such conformity can be a positive contributor to cooperation, conformity can suppress innovation and be a factor in rigidity. I will return to this point later.
Third, we suggested that rigidity can develop as a result of a trade-off
Recent work on robustness – which focuses on performance characteristics – is reaching the conclusion that robustness in one realm is often achieved at the cost of vulnerability in another (Anderies 2006; Anderies, Janssen and Ostrom 2004). More specifically, the Hohokam canal irrigation system was highly robust to fluctuations in rainfall because it provided a buffer from temporal variation. But that robust buffer contributed to the creation of a system that was increasingly vulnerable to other social and ecological perturbations. There are always trade-offs.
Diversity
To address the nature of the contribution of social and subsistence diversity to resilience, we used archaeological information from across the south-western US and northern Mexico. The resilience literature, drawing heavily from ecology, uses concepts of diversity defined in terms that are thought to enhance resilience in ecosystems by absorbing disturbance and by regenerating and reorganizing the systems following disturbance. To extend these ideas about diversity to social change is complex (Walker et al. 2006, 6). There are aspects of diversity (e.g. material culture styles) in human systems that do not conform to strict definitions of either functional or response diversity. In addition, diversity in both ecological and social contexts can be expensive, and in social contexts it may detract from the capacity for collective action. In our research, we consider diversity in two general arenas: socially constructed diversity and subsistence-resource diversity.
Socially constructed diversity
The ‘rigidity trap’ I just discussed involves suppression of innovation in order to resist change, with the result that eventual transformations are severe (Hegmon et al. 2008). We extended our focus on understanding the factors that contribute to rigidity by examining the relative advantages of diversity and collective action in different settings, and the role of material culture diversity.
Currently, we are evaluating the hypothesis that lack of symbolic diversity, as expressed in material forms, contributes to vulnerabilities toward severe transformations. Across our cases, we focus on finding the times and places in which material diversity was lowest and on determining whether these contexts immediately preceded severe transformations. We have found that across the south-western cases, where leadership is not institutionalized and often not strongly hierarchical, symbolic diversity, as expressed in the heterogeneity of painted designs on ceramic vessels, is strongly negatively correlated with population density – the highest population levels are associated with the lowest levels of ceramic diversity. And we found that the contexts of highest population density in conjunction with least ceramic diversity immediately preceded the most severe transformations (although not in every case). We can understand the relationship between population density and ceramic homogeneity in these relatively small-scale systems as a way to encourage conformity and contribute to collective action. This ‘advantage’, however, may ultimately contribute to severe transformations – major declines in population and collapses of social institutions.
Subsistence-resource response diversity
We examined the contribution of food resources to reducing vulnerability under varied climatic conditions (Anderies, Nelson and Kinzig 2008). In parts of the pre-Hispanic south-western US and northern Mexico considerable effort was devoted to agave cultivation (see e.g. Fish et al. 1985), even though the annual caloric contribution of agave may have been minor. Our research examined this apparent paradox in terms of the different planting–harvesting cycles of maize and agave and especially their differing susceptibility to rainfall fluctuations in the Malpaso Valley area of northern Mexico. Using modelling we found that diversifying cultivated foods by adding agave to a maize-based system was beneficial in reducing vulnerability to climate change only under a limited array of climatic circumstances. In the Malpaso Valley, agave could reduce vulnerability to low rainfall conditions when variability in rainfall is also low. Otherwise the extra work of agave farming did not contribute to resilience. We also examined a variety of agave taxa and found that ‘given the labor investments required, highly diverse but randomly assembled communities may actually be less useful than less diverse assemblages with a careful “matching” of climatic and plant physiological conditions. In other words, there are real “transaction costs” associated with maintaining a diverse assemblage’ (Anderies, Nelson and Kinzig 2008). Diversity in the responses of essential food resources to climatic change and fluctuation may be more important than simple plant-food diversity as a contributor to the resilience of subsistence, just as it is to the resilience of ecosystems (Scholes and Walker 1993; Walker et al. 2006).
These three studies bring a long-term perspective to issues of concern in contemporary policy-making. Our long-term sequences help us see that:
1. Isolation can contribute to rigidity and eventually to the severity of collapse and transformation. That is certainly a lesson worth keeping in mind in today's world as we grapple with global connections.
2. Diversity and conformity in the social realm have trade-offs: conformity may be a positive contributor to cooperation and consensus-based decision-making, yet conformity – as the suppression of innovation – may contribute to rigidity and the magnitude of transformation. Again, a relevant lesson as we consider the values we hold regarding conformity and diversity.
3. Diversity has costs as well as benefits. In the subsistence realm it may be more productively examined in terms of the responsiveness of plants to varied climate conditions than as a simple function of the number of plant kinds. What kind of diversity we promote in today's world is as important as the simple value of diversity.
Any one of the insights might be obvious to archaeologists, given our understanding of the long term. But they are not obvious to many ecologists, policy-makers, and other environmentalists seeking ways to understand human–environment dynamics and contribute to the resilience of our contemporary social–ecological systems.
Doubts and concerns
I agree with Shannon Dawdy that archaeologists have much to offer. She also expresses concerns about the politicization of archaeology as well as archaeologists’ interests in consulting with numerous communities and constituencies. My perspective on these concerns differs from hers.
The first concern has been expressed by numerous archaeologists, who are attentive to how archaeologists represent the past and how modern agendas influence archaeological questions and interpretations. Dawdy asks whether there is a ‘safe way to apply archaeology to contemporary social or political conditions without the risk that it will be harnessed for ill’ (p. 132). ‘Once we open the door, accepting that archaeology should be useful, can we control the uses to which it is put, and by whom?’ (p. 132). I believe that the answer is ‘no’ regardless of whether we see archaeology as useful. Much of our work is on public record and can be seen by others as relevant to their issues whether we engage in those issues or not. We cannot be certain that our work will not be misused or our insights manipulated to serve a particular political end. We can, however, acknowledge the influence of contemporary politics on our ideas and reflect on the way we use words and concepts as well as the way others interpret what we say. From my own experience, working in the south-western US, I know that archaeological research on ‘abandonment’ of villages, locales and regions has been misinterpreted by non-archaeologists. The word ‘abandonment’ carries the connotation of giving up claim or ownership, which supports a political agenda of usurpation of Native American lands that are and have been their homelands for many centuries, whether they are formally occupied in the Euro-American sense or not (see Nelson and Schachner 2002).
Her second concern, about the involvement of archaeologists with local communities and with heritage, is misguided, from my perspective. Dawdy argues that ‘[p]ublic archaeology and community archaeology are ultimately more self-serving than helpful’ (p. 132) and that community archaeology is an ‘archaeology of apology’ (p. 137). ‘Can you imagine . . . political scientists going door to door to ask community members to be involved as collaborators in their research projects’ (p. 138). Yes, I can. Public and private universities, community colleges, the National Science Foundation and many other research-funding institutions are calling for community-embedded research and for careful consideration of the impacts of research on society. At ASU, the NSF-funded Decision Center for a Desert City focuses on the integration of public and research concerns about water and water use. Political scientists, sociologists, geographers, ecologists and climatologists collaborate and consult with communities in the design of research and interpretation of outcomes from climate modelling to educational policy (Cutts, Saltz and Elser 2008; Gober 2008; White, Corley and White 2008). In addition, exceptional cultural resource management firms such as Desert Archaeology and Statistical Research, headquartered in Tucson, have active foundations that promote community involvement in research, preservation and education (www.cdarc.org; www.srifoundation.org). They proceed from the perspective that the value of archaeological work and archaeological resources is not to be determined solely by archaeologists. Their efforts document how research, resource management, education and community involvement can operate hand in hand. Collaborations with descendant and local communities such as the Center for Desert Archaeology's San Pedro Project (Ferguson and Colwell-Chanthaphonh 2006) and Statistical Research's Western Papaguería research (Altschul and Rankin 2008) are but two examples that have benefited everyone.
So I conclude, as does Dawdy, that archaeology can contribute much to informing our thinking about contemporary issues, but I believe, in contrast to Dawdy, that we can and must accomplish this in partnership with varied communities and with concern for heritage and resource preservation. We have much to offer.
Acknowledgements
The ASU research described in the first section of this paper is supported with an NSF Biocomplexity grant (SBE/CNH 0508001) and generous sharing of data by Bill Doelle, the New Mexico Laboratory of Anthropology, the University of Arizona Tree-Ring Laboratory, the Coalescent Community Data Base Project, and Crow Canyon Archaeological Center.
