A wide range of plant food was recovered within the cave deposits of Guilá Naquitz, including acorn, pinyon, cactus fruits, hackberries, and most importantly, the wild forms of bottle gourd, squash and beans. Researchers have taken this to be evidence of early cultivation of bottle gourd, squash and beans.
Three cobs of teosinte (the wild progenitor of maize) were found within the deposits and direct-dated by AMS radiocarbon dating to about 5400 years old; they show some signs of domestication. If that is correct, the Guila Naquitz domesticated teosinte is older than that from the Tehuacan valley sites by about 700 years.
Guilá Naquitz was excavated in the 1970s by a team from the University of Michigan led by Kent Flannery.
Sources
Benz, Bruce. 2005. Archaeological evidence of teosinte domestication from Guilá Naquitz, Oaxaca. Proceedings of the National Academy of Sciences 98(4):21042106.
Flannery, Kent V. 1986. Guilá Naquitz: Archaic Foraging and Early agriculture in Oaxaca, Mexico. Academic Press, New York.
Marcus, Joyce and Kent V. Flannery. 2005. The coevolution of ritual and society: New 14C dates from ancient Mexico. Proceedings of the National Academy of Sciences 101(52):1825718261

