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Pearsall, Deborah M.1; Karol Chandler-Ezell2 and James A. Zeidler3 1 pearsalld@Missouri.edu 2 Karol@epi.wustl.edu 3 jzeidler@cemml.colostate.edu During the late 1970s phytolith analysis of sediments from domestic and ceremonial contexts at Real Alto, a Valdivia period (4500 BC to 2100 BC, cal.) site in southern Guayas Province, Ecuador, revealed the presence of maize (Zea mays) and achira (Canna) (Pearsall 1978, 1979). Later reanalysis of sediments added arrowroot (Maranta), squash (Cucurbita), and gourd (Lagenaria siceraria) to the assemblage of cultivated or domesticated plants present at the site, and maize presence was confirmed by applying a discriminate function for classification of cross-shaped phytoliths as wild or maize (Pearsall and Piperno 1990; Pearsall 2000, 2003). The question remains, however, of the role of domesticated plants in subsistence: was Valdivia culture agriculturally based? What role did maize play in diet? Because collagen is poorly preserved in human skeletal remains at the site, it is impossible to evaluate the importance of maize in diet using stable carbon isotope analysis. There are also few charred botanical remains preserved and recovered from the site. To address the question, how important was agriculture in prehistoric Ecuador, new phytolith research was carried out, and starch granule analysis was applied for the first time to site materials. A total of 49 ground stone tools from four Valdivia 3 period structures have been analyzed for phytolith and starch residues. In addition, 46 samples of dental calculus from human dentitions are being studied for microfossils (results of scanning the dental calculus samples are pending). The approach taken in the new study is to examine the ubiquity, or percentage presence, of indicators of various crop plants on tools directly associated with crop processing, and in human dental calculus, which is directly associated with consumption. If maize were a central component of diet, for example, we might expect to see use of dried grain (easy to store, a good source of bulk carbohydrates) by all households and individuals. If diet were a mix of maize, root crops, and wild plant resources, a pattern typical of tropical forest agriculturalists, tools and dentitions should reflect this diversity. Ceremonial, rather than domestic use of maize or other crops would be revealed by differences in ubiquity patterns between tools recovered in domestic and ceremonial contexts. Potential complications to this approach include differential preservation of starch granules of different crops and between tool surfaces and dental calculus, differential deposition of phytoliths produced in different plant tissues, and the taxonomic precision of identifications. Artifacts from Structure 20, a domestic household for which unwashed tools were available, were studied first. Maize was identified on all 17 tools studied, which include both shaped grinding stones and unworked pounders (Pearsall et al. 2004). Maize starch granules (N=91, on 17 tools) were more common than maize cob phytoliths (N=17, on 7 tools) on tool surfaces. From these results we conclude that this domestic household routinely processed maize, and that maize starch is more likely to be incorporated into grinding and pounding stone surfaces than are maize cob phytoliths (present in chaff adhering to the grains being processed). Results of scanning tool residues for maize starch are also available from two other domestic structures, Structure 1 and Structure 10, and one ceremonial structure, Structure 7, located on the Funerary Mound in the central plaza of the site. Tools from these structures were washed in the field laboratory. Maize starch granules are present on 12 of 15 tools from Structure 1 (80% percentage presence), and 5 of 6 tools from Structure 10 (83% presence). Maize starch also occurred on tools from ceremonial contexts: 9 of 11 tools from Structure 7 (82% presence) had maize granules. One might anticipate reduced occurrence of starch on washed tools in comparison to unwashed ones, but there is no reason to suppose that washing removed residues more from one set of tools than from another. It seems reasonable to conclude that data from Structures 1, 7, and 10 are comparable, and therefore that maize was commonly processed in each structure, domestic and ceremonial. Phytolith results from the Structures 1, 7, and 10 tools are pending. We have also determined that many tools from the Structure 20 household were multipurpose: in addition to grinding or pounding maize, tools were used for processing roots, rhizomes, and fruits (Chandler-Ezell et al. nd). Phytoliths produced in manioc (Manihot esculenta) root and leaves were recovered from 5 tools and manioc starch on 1; arrowroot (Maranta arundinacea) starch was found on 8 tools; lleren (Calathea) phytoliths on two; Canna starch or phytoliths on 6. In addition many tools preserved transport tissues and parenchyma produced by underground storage organs, and some tools transport elements produced by fruits. Fragments of altered starch were also observed on tools. Phytolith and starch results for root, rhizome, and fruit occurrence are pending for Structures 1, 7, and 10. Conclusions must be considered preliminary at this stage, until the studies that are pending are completed. We can conclude with confidence, however, that maize was not only present in domestic contexts in the Valdivia 3 occupation at Real Alto, but that it was ubiquitous or nearly so on tools in each of the domestic structures examined. This pattern suggests routine use of the crop. Maize was not restricted to the domestic sphere, however, but was also present on tools recovered from the ceremonial area of the site. This suggests a role for the crop in feasting or mortuary rituals. The inhabitants of Real Alto were not dependent on maize alone: manioc is documented for the first time at the site in this study, as is lleren. These root/tuber crops, as well as arrowroot and achira, are not as commonly recovered on tools as maize—whether this indicates a secondary role to maize, or differential preservation or deposition are issues for further discussion. References CHANDLER-EZELL, Karol, Deborah M. PEARSALL, and James A. ZEIDLER. nd. Phytolith and starch evidence of roots and tubers: The raw and the cooked at Real Alto, Ecuador. Manuscript. PEARSALL, Deborah M. (1978) Phytolith analysis of archeological soils: Evidence for maize cultivation in Formative Ecuador. Science 199:177-178. PEARSALL, Deborah M. (1979) The application of Ethnobotanical Techniques to the Problem of Subsistence in the Ecuadorian Formative. Unpublished Doctoral Dissertation, Department of Anthropology, University of Illinois, Urbana. PEARSALL, Deborah M. (2000) Paleoethnobotany. A Handbook of Procedures (Second Edition). Academic Press, San Diego PEARSALL, Deborah M. (2003) Plant food resources of the Ecuadorian Formative: An overview and comparison to the Central Andes. In: J. S. Raymond and R. L. Burger, editors, Archaeology of Formative Ecuador, A Symposium at Dumbarton Oaks. Dumbarton Oaks, Washington DC. Pp. 213-257. PEARSALL, Deborah M. and Dolores R. PIPERNO (1990) Antiquity of maize cultivation in Ecuador: Summary and reevaluation of the evidence American Antiquity 55: 324-337. PEARSALL, Deborah M., Karol CHANDLER-EZELL, and James A. ZEIDLER (2004) Maize in ancient Ecuador: Results of residue analysis of stone tools from the Real Alto site. Journal of Archaeological Science 31:423-442.
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