The Classic-Postclassic Transition in Oaxaca

Part of: Society for American Archaeology 90th Annual Meeting, Denver, CO (2025)

This collection contains the abstracts of the papers presented in the session entitled "The Classic-Postclassic Transition in Oaxaca" at the 90th annual meeting of the Society for American Archaeology.

This session discusses preliminary results of an ongoing 5-year interdisciplinary project addressing the Classic-Postclassic transition along the Río Verde drainage basin of Oaxaca, Mexico. The research focuses on two interrelated but contrasting ecological regions: the lower Río Verde Valley in the semi-tropical lowlands and the Nochixtlán Valley in the temperate highlands. As discussed in the session, preliminary paleoecological research in Oaxaca and beyond suggests a period of climatic drying at this time, which may have negatively impacted agriculture. Archaeological papers in the session examine changes in the lives of commoners with a focus on shifts in domestic economy, diet, and the health of people potentially linked to climate change. We focus on commoners because they were the vast majority of the population, the primary food producers and would have been most directly affected by a decline in agricultural productivity. The interregional comparison also contributes to evaluating the impact of climate change because in Nochixtlán agriculture is highly susceptible to drought, while in the lower Verde higher mean annual rainfall and non-agricultural resources likely buffered domestic economies. Session papers also consider changes in ritual, political organization, long-distance trade, and the use of space.

Other Keywords
Collapse • Environment and Climate • Mesoamerica: Pacific Coast • Mesoamerica: Oaxaca or Southern Highlands

Resources Inside This Collection (Viewing 1-13 of 13)

  • Documents (13)
Documents
  • Biological History of the lower Río Verde Valley, Oaxaca, Mexico: An Investigation into Infectious Disease During the Classic-Post Classic Transition at Río Viejo (2025)
    DOCUMENT Citation Only Arion Mayes.

    This is an abstract from the "The Classic-Postclassic Transition in Oaxaca" session, at the 90th annual meeting of the Society for American Archaeology. This research investigates population health and infectious disease at the site of Río Viejo during the Classic-Post Classic transition; testing the hypothesis that treponema was endemic in Oaxaca, specifically the lower Río Verde Valley along the Pacific coast, and identifiable in a congenital New World form through dental stigmata, as well...

  • The Ceramics of the PRV24, a Petrographic Approach (2025)
    DOCUMENT Citation Only Pamela Garcia Ramirez.

    This is an abstract from the "The Classic-Postclassic Transition in Oaxaca" session, at the 90th annual meeting of the Society for American Archaeology. During the fieldwork of the PRV22-24 the recovered ceramics were analyzed by conventional methods that include a detailed analysis of the primary contexts excavated, such as ovens, termination deposits, and middens. From the PRV24 collection a sample was taken to study through petrographic analysis. The sample focuses on the fine ceramic...

  • Climatic variability during the Classic to Postclassic transition in central Mesoamerica. (2025)
    DOCUMENT Citation Only Margarita Caballero.

    This is an abstract from the "The Classic-Postclassic Transition in Oaxaca" session, at the 90th annual meeting of the Society for American Archaeology. Central-Mesoamerica has several lacustrine basins that stand out as particularly sensitive to moisture fluctuations. The lacustrine sediments they preserve represent good records of hydroclimate variability, which in this region are interesting because they can give a valuable paleoclimatologic background for the analysis of human –...

  • ‘Collapse’ and Population Health in Oaxaca: How the Classic-Postclassic transition influenced health and disease at Río Viejo in the lower Río Verde Valley. (2025)
    DOCUMENT Citation Only Zachery Clow.

    This is an abstract from the "The Classic-Postclassic Transition in Oaxaca" session, at the 90th annual meeting of the Society for American Archaeology. The Classic-Postclassic transition is hypothesized to have affected health outcomes in the lower Río Verde Valley of Oaxaca, Mexico. Set within a multiscalar approach, this research examined the relationships between health, diseases, culture, climatic changes, and the physical manifestations left behind on the skeleton from a biocultural...

  • ¿Cómo se regresa a una ciudad abandonada?: documentando la reocupación posclásica del Cerro Jazmín (2025)
    DOCUMENT Citation Only Itzel Chagoya Ayala.

    This is an abstract from the "The Classic-Postclassic Transition in Oaxaca" session, at the 90th annual meeting of the Society for American Archaeology. Cerro Jazmín fue una importante urbe del Formativo tardío en el Valle de Nochixtlán, Mixteca Alta, Oaxaca. La ubicación del Cerro Jazmín fue estratégica como nodo entre los Valles de Oaxaca, la Mixteca Baja, Puebla y la Cuenca de México, lo que convirtió al Cerro Jazmín en una ciudad accesible, y a su vez, influenciada por los cambios...

  • Figurines found in the Low Valley of Rio Verde, a typology of commoner’s life representations in Rio Viejo during the Late Classic and the Early Postclassic Periods (2025)
    DOCUMENT Citation Only Ishbel Torres.

    This is an abstract from the "The Classic-Postclassic Transition in Oaxaca" session, at the 90th annual meeting of the Society for American Archaeology. During the Classic and Postclassic periods, Río Viejo maintained continual occupation by various groups, leading to significant societal, ritual, environmental, economic, and political changes in the region. The site's prominent position in human development facilitated the expansion of inhabitants' worldviews, resulting in the creation of...

  • Late Classic and Early Postclassic residential excavations at Rio Viejo, Coast of Oaxaca (2025)
    DOCUMENT Citation Only Akira Ichikawa.

    This is an abstract from the "The Classic-Postclassic Transition in Oaxaca" session, at the 90th annual meeting of the Society for American Archaeology. The collapse of ruling institutions at the end of the Classic period around 800 CE is widely regarded as one of the most complex topics within Mesoamerican archaeology. The Proyecto Rio Verde (PRV) is investigating the role of climate change and human impact on the environment in the collapse of the Rio Viejo polity in the lower Rio Verde...

  • An Overview of Interdisciplinary Research on the Classic-Postclassic Transition in Oaxaca (2025)
    DOCUMENT Citation Only Arthur Joyce.

    This is an abstract from the "The Classic-Postclassic Transition in Oaxaca" session, at the 90th annual meeting of the Society for American Archaeology. This paper provides an overview of ongoing interdisciplinary research on the Classic-Postclassic transition in Oaxaca. The research focuses on two interrelated but contrasting ecological regions: the lower Río Verde Valley in the semi-tropical lowlands and the Nochixtlán Valley in the temperate highlands. Preliminary paleoecological research...

  • Population Distance at the site of Río Viejo During the Classic-Postclassic Transition (2025)
    DOCUMENT Citation Only Abilene Ayala.

    This is an abstract from the "The Classic-Postclassic Transition in Oaxaca" session, at the 90th annual meeting of the Society for American Archaeology. This research investigates population dynamics in the Lower Río Verde Valley (LRVV) of Oaxaca, through the analysis of non-metric dental traits from the prehispanic archaeological site Río Viejo during the Classic to Postclassic Period transition. The LRVV has been continuously inhabited since the Early Formative and has experienced...

  • Resultados preliminares de la intervención arqueológica en unidades domésticas habitacionales en el sitio de Río Viejo: Secuencia ocupacional de las fases Yuta Tiyoo y Yugüe en operación C (2025)
    DOCUMENT Citation Only Ivonne Cruz Sosa.

    This is an abstract from the "The Classic-Postclassic Transition in Oaxaca" session, at the 90th annual meeting of the Society for American Archaeology. Esta investigación se centra en dar a conocer la evidencia material cultural recuperada mediante los trabajos de excavación en el sitio de Río Viejo, en el área determinada como operación C dentro del Proyecto Río Verde en la temporada 2024. Se tuvo como principal objetivo el obtener información relacionada con los aspectos culturales,...

  • Resultados preliminares del proyecto Rio Verde 2022 y 2024, Operación B: Usos y ritualización del espacio. (2025)
    DOCUMENT Citation Only Andrea Nava Esparza.

    This is an abstract from the "The Classic-Postclassic Transition in Oaxaca" session, at the 90th annual meeting of the Society for American Archaeology. En Mesoamérica durante los períodos del Clásico y Posclásico existió una época de cambios ecológicos y antropogénicos, los cuales derivaron en conflictos internos en las sociedades y los grupos que las componían. Rio Viejo localizado en la costa Oaxaqueña, es un ejemplo de los cambios existentes entre ambos períodos. Específicamente nos...

  • Sex and Gender in Bioarchaeology: Revisiting Methodology, Application of Different Perspectives, and the Role of Associated Funerary Objects at Río Viejo (2025)
    DOCUMENT Citation Only Elaine Aguayo Ortiz.

    This is an abstract from the "The Classic-Postclassic Transition in Oaxaca" session, at the 90th annual meeting of the Society for American Archaeology. Bioarchaeologists create biological profiles of past individuals through skeletal analyses to provide an overall picture of who they may have been during life including aspects of identity such as sex and gender. However, there is growing criticism within bioarchaeology about the use and definition of these concepts, and their application...

  • The Use of Plants at Río Verde: Macrobotanical and Microbotanical Data (2025)
    DOCUMENT Citation Only Eloi Berube.

    This is an abstract from the "The Classic-Postclassic Transition in Oaxaca" session, at the 90th annual meeting of the Society for American Archaeology. This paper discusses the use of plants at Río Verde through the lens of paleoethnobotany. I will present the results of the macrobotanical analysis from the two field seasons (2022 and 2024) and the preliminary results of the microbotanical analysis of the samples collected in 2022. By combining macrobotanical remains (mainly seeds),...