How the Olmec used bitumen in ancient Mesoamerica

Bitumen, found in abundance in Mesoamerica’s southern Gulf Coast region in natural seeps and in many archeological contexts, is an important economic resource and exchange item that has received little consideration in Mesoamerica. Analyses of archeological, ethnoarcheological, and experimental data provide insights on the organization of bitumen processing activities, and the end product (archeological bitumen), which the Olmec (1200–400 BC) used in the production of many items. Archeological data are derived from investigations at El Remolino and Paso los Ortices— two Early Formative period levee sites in the San Lorenzo Olmec region. Our findings suggest that among the Olmec, bitumen processing was organized as a specialized activity, involving multiple production stages, but not necessarily elite involvement or control.     

A Multi-Method Approach to Reconstructing Occupational History and Activity Areas: A Case Study at the Formative Site of Tlalancaleca,Central Mexico

While surface collection constitutes an important component of field research at the site and regional levels, the association between surface and sub-surface materials needs to be examined through independent lines of evidence. This study employed manual bucket auger probing and soil geochemistry at the Formative site of Tlalancaleca, Central Mexico (800 b.c.–a.d. 250), to evaluate the results of surface collection and to understand the formation process of the anthropogenic landscape. The combined results at one of the largest architectural complexes at Tlalancaleca indicate that it was built during the Late Formative period (500–100 b.c.) and rebuilt during the subsequent Terminal Formative period (100 b.c.–a.d. 250), which is corroborated by radiocarbon dates. Moreover, the results suggest segregated uses of space such as cooking/storage, waste disposal, and craft production areas within the complex. Overall results demonstrate the effectiveness of this multi-method approach for reconstructing occupational history and activity areas.     

Tooth Wear Related to Marine Foraging,Agro‐Pastoralism and the Formative Transition on the Northern Chilean Coast

Occlusal surface wear scores were examined in a sample of 200 Formative period (1500 bc–ad 500) skeletons from the lower Azapa Valley in northwest Chile. Wear rate and plane (angle) were additionally evaluated using a subsample of paired first and second mandibular molars. The Formative period represents the transition from marine foraging to agro‐pastoral dependence in the region, and differences in oral pathology indicate that diet varied by site location (coast vs valley interior) but not by archaeological phase (early vs late). We predicted that occlusal wear would demonstrate similar patterns, resulting from differences in food consistency, and therefore hypothesised that in coastal groups consuming greater quantities of foraged foods, occlusal surfaces should wear faster and exhibit flat molar wear, whereas among valley interior groups consuming greater quantities of agro‐pastoral products, these should wear slower but exhibit more angled molar wear. Heavier posterior tooth wear was identified among coastal residents, but rate and angle of molar occlusal attrition did not differ significantly by location. Heavier overall wear and a steeper molar wear plane were identified during the early phase indicating that food consistency varied somewhat over the course of the Formative period. Overall, the results indicate that, although limited differences in tooth wear exist by site location, wear varied more over time likely reflecting a gradual transition from foraging to agro‐pastoral dependence in the lower Azapa Valley. Although oral health indicators point to differences in dietary investment by location, maintenance of a mixed subsistence economy likely sustained a comparative consistency of foodstuffs. Copyright © 2011 John Wiley & Sons, Ltd.     

Reassessing the Developmental and Chronological Relationships of the Formative of Coastal Ecuador

The Ecuadorian Formative was initially interpreted as a result of long-distance diffusion, and migration, more recent research has changed our perception of the Valdivia, Machalilla, and Chorrera culture complexes. In this analysis, these archaeological investigations are reassessed in order to reevaluate our understanding regarding the nature of these prehistoric cultures. Formative chronologies, distributions, interrelationships are reviewed in the light of Pre-Hispanic occupations in El Oro Province. Previous investigations on the Ecuadorian littoral are examined. Results indicate (1) Valdivia and Machalilla are part of the same ceramic tradition and (2) the interrelationships of these complexes to Late Formative Period ceramic sequences are more complex than previously assumed. (3) A major adaptive shift related to an increased dependence upon agriculture occurred during Valdivia VI–VIII, and continued into the Late Formative with the widespread distribution of Chorrera related material culture. (4) Long-distance interaction with the Ecuadorian highlands resulted in the spread of what may be termed a Chorrera horizon and formed the basis of subsequent Andean cosmology where it was symbolically represented according to local and regional artistic canons and over a vast area of Andean South America.     

The Formative Period on the south coast of Peru: A critical review

Previous and current fieldwork has generated a significant body of data on the occupation of the south coast of Peru during the Formative Period (ca. 3800-2200 B.P.). These data are placed in a synthetic framework and evaluated and compared to the trajectory of cultural development in the better studied regions of the Central Andes. Critical review of this panorama necessitates consideration of the relative chronological framework and definition of the Formative Period, the parameters and validity of the south coast as a culture area, contacts south coast societies sustained with other Central Andean regions, and the role of monumental architecture in the rise of complex society.     

New radiometric dating of water management features at the prehistoric Purrón Dam Complex,Tehuacán Valley,Puebla, México

Recent investigations at the prehistoric Purrón Dam Complex in the Tehuacán Valley of southern Puebla, México applied radiometric dating to more securely date the complex. Ceramic-based dating in the 1960′s placed the Dam's origin to the Formative Period. While Formative Period origins are widely accepted, the chronology lacks resolution and direct dates. Samples from impounded sediments behind the dam and from prehistoric canal fill were dated through Optically Stimulated Luminescence (OSL) as well as both standard ¹⁴C and accelerated mass spectrometry (AMS) assays. These samples directly date the functioning of the water management features within the complex. The results confirm the Formative Period origins of the Purrón Dam, and offer new insights into the construction and functioning of the dam and irrigation system.     

Detecting and mapping buried buildings with Ground-Penetrating Radar at an ancient village in northwestern Argentina

We describe an archaeo-geophysical investigation performed near the Palo Blanco archaeological site, Catamarca, Argentina. A large area beyond the northern limit of the site was explored with the Ground-Penetrating Radar (GPR) method in order to detect new buildings. The exploration showed signals of mud-walls in a sector that was located relatively far from the previously known buildings. A detailed survey was performed in this sector, and the results showed that the walls belonged to a large dwelling with several rooms. The discovery of this dwelling has considerably extended the size of the site, showing that the dwellings occupied at least twice the originally assumed area. High-density GPR surveys were acquired at different parts of the discovered building in order to resolve complex structures. Interpreted maps of the building were obtained. Different characteristics of the walls were satisfactory determined, in spite of the low contrast of the dielectric constant at their interfaces and the noticeable spatial fluctuations of the signals due to wall collapses.     

Olmec archaeology: A half century of research and its accomplishments

The Olmec of Mexico's southern Gulf coast (3100-2450 B.P.) are the most famed of Formative period Mesoamerica's early complex cultures, and are particularly noted for their elaborate stone monuments. After five decades of research, scholars remain in sharp disagreement on what the archaeological record means with regard to the impact the Olmec had on social and political evolution in Mesoamerica. A discussion of interpretive problems and a review of 50 years of Olmec archaeology illustrates reasons for the disagreements, as well as the type, quantity, and quality of data that have been recovered from excavations. Those show that, until recently, knowledge of the Olmec has been based primarily on two limited pre-1970 data sets. New research is discussed, and topical issues in Olmec archaeology are treated in detail.     

New light on the prehistoric Purrón Dam Complex: Small corporate group collaboration in the Tehuacán Valley,Puebla, México

Abstract

The 2003 and 2004 surveys at the Purrón Dam Complex (PDC) demonstrate the value of resurveying previously studied areas. Additional habitation sites, water management features, a cave with pictographs, and a major canal were discovered, increasing the number of recorded sites from eight to 57. From this survey, the collected ceramics and a synthesis of 12 chronometric dates suggest that water management was initiated in the complex by Early Formative times at ca. 1050–1100 b.c., and that the Purrón Dam was completed by the Middle Formative Period (ca. 650–450 b.c.), when settlements were small and decentralized. This challenges previous interpretations that place the PDC florescence during the Early Classic Period (ca. 150 b.c.–a.d.250), a period with larger aggregated communities displaying social ranking. The results of our survey have implications for understanding the links between political complexity and agricultural intensification, and support recent ethnographic and archaeological research discrediting the argument that increasing social complexity necessarily leads to the construction of large water management systems.     

Swidden agriculture,village longevity,and social relations in Formative central Tlaxcala: Towards an understanding of macroregional structure

Understanding social change within early village societies requires analysis at multiple scales. In this paper, we focus on macroregional structure in the Formative era of Central Mexico, based on excavations at village sites in Tlaxcala. A macroregional scale is particularly important for contextualizing developments in the study region. Rapid political evolution after 900 BC built on a legacy of organizational innovations in settled communities to the south. The earliest farmers in central Tlaxcala practiced a system of swidden agriculture developed at lower-lying elevations. Practiced on the erodible slopes of central Tlaxcala, that system led to the widespread degradation of farmland. Consequences at the village scale involved chronic instability of settlement and recurring localized stress on faunal resources.