Proyecto Costero: Arcaico-Formativo

This project involves a team effort designed to explore the transition from foraging wild foods to cultivating domestic plants on the part of ancient peoples once living on the south Pacific coast of Mexico.  The project was designed to investigate this issue in two locations: near Acapulco on the coast of Guerrero, and in the Chiapas coast in the municipality of Acapetahua.  The ancient people of Guerrero are called the Ostiones people, whereas those of Chiapas are known as the Chantuto people. 

The senior scholars of archaeological team consisted of a palynologist (John G. Jones), geologist (Teresa Ramirez Herrera), and archaeologists (Douglas J. Kennett, Hector Neff, and Barbara Voorhies), along with student and local assistants.  In January 2003 we worked in Guerrero, whereas in January 2005 we worked in Chiapas. Both field seasons were supported by a National Science Foundation grant to Douglas J. Kennett.

My task during the 2005 field season was to excavate the El Chorro shell mound.  This is the smallest of a group of five shell mounds clustered around a linked chain of coastal lagoons. This mound is now only 5.5 m high and rises to a single steep peak, suggesting that it has not had time to erode significantly (Voorhies 2004: Fig. 2.2).  Prior to our work, this shell mound had never been investigated archaeologically. We dug two small test pits. The first one was ended at the 5.40 m level because we hit the water table and it became too dangerous to dig deeper. The second small test pit was excavated to increase the sample of artifacts from the upper, sherd-bearing stratum at the site.  It ended at the 2.2 m level.

A view of the El Chorro shellmidden

The Late Archaic period deposits that consisted of almost pure bedded clam shell, contained very little in the way of other ecofacts or artifacts. The paucity of site contents was striking even in comparison with other shell mounds in the area in which scarcity of bones and artifacts has been noted previously (e.g.,  Voorhies 2004).  The only significant items in the Late Archaic deposits were vertebrae of small fish. Bones from other animals were extremely rare and no artifacts were recovered except for small fragments of obsidian.

In addition to the excavations, Doug Kennett took a sediment core from the base of the mound. This core yielded an additional 4.3 m of material below the current basal level of the mound.  When completed, analysis of the contents of the core will give us additional data about the formation history of this mound.

Coring at edge of the El Chorro site