Chronological adjustment regarding Zapoteca Culture development that includes a new one-hundred years period denominated Transition, corresponding to 850-950 AD, could help define causes of Monte Alban, Yagul and Xaaga abandonment.

This is proposed by Robert Markens, researcher at Universidad Autonoma Benito Juarez de Oaxaca, based on ceramic material study that corresponds to the period where ancient Zapoteca cities declined.

Sixty years ago, with the first Monte Alban explorations, several generations of archaeologists’ studies, included Alfonso Caso’s, have presented a gap in Oaxaca Central Valley ceramic chronology corresponding to transition from the end of Late Classic (850 AD) to beginning of Early Post Classic (950-1200 AD).

This period is important in Mesoamerican Cultures at Zapoteca region studies because it was the lapse when most representative cities were abandoned.

During his participation at the 5th Monte Alban Round Table, Robert Markens presented a new dating series based on radiocarbon tests applied to regional ceramics that could clear out the temporary transition from Classic to Post Classic, helping to determine an age that has provoked conflict to researchers in the past.

The investigator commented that his study aims to help clearing out Monte Alban depopulation towards the end of Late Classic period, a much severe and broad phenomenon than thought, with similar effects in other nucleus of Oaxaca Valley.

His proposal is based on 13 new dating figures obtained with radiocarbon method, applied to samples from Lambityeco, Macuilxochitl and Xaaga sites during 2002 and 2003. They confirm depopulation at Monte Alban between 850 and 900 AD, which also affected other important Zapoteca cities such as Cuilapan, Lambityeco, Xaaga, Macuilxochitl and Yagul.

Studied material corresponds to period known as Transition, and has special features such as been created with brown and beige paste, with a cruder technique than ceramics manufactured between 600 and 850 AD.  Their bases are thicker than the ones made in the next period, between 1200 and 1521.

Zapoteca civilization decline in Classic period and its relation with Mixteca culture happened suddenly near 850 AD, after inhabiting the region more than 1000 years.

Further information about the 5th Monte Alban Round Table is available at