Ancient DNA recovered from pottery at the Etowah Mounds in present-day Georgia indicates that cacao was consumed there about 800 to 900 years ago, during the 11th and 12th centuries. The results, reported in PLOS One, provide evidence for cacao use in the Mississippian world east of the Mississippi River.
Researchers examined three pottery sherds excavated from feasting pits associated with construction of the site’s first platform mound. The residues preserved inside the vessels contained DNA that the team compared with the cacao genome. Because ancient residues can include soil bacteria, other plants and environmental contaminants, the researchers filtered out DNA from sources unrelated to cacao.
The Etowah site includes six large prehistoric earthen mounds, a village and plazas spread across 54 acres (22 hectares) along the Etowah River. The pottery fragments were previously tested using chemical methods, which detected caffeine but could not establish that cacao was present. Yaupon holly, a plant native to the region, contains some of the same chemical markers as cacao, including caffeine and theobromine.
The genetic evidence offered a more direct way to distinguish the plants. The study authors wrote that ancient DNA confirmed the site’s inhabitants consumed cacao.
Cacao grows only in tropical regions, so its presence at Etowah indicates that it reached Georgia through contact with people in or near areas where the plant was cultivated or grew. The researchers suggest it may have moved through long-distance networks that circulated goods, people and ideas across the Americas before European colonization.
The evidence does not establish where the cacao originated or which route brought it to Etowah. Instead, the finding expands the documented range of cacao consumption and adds evidence that the plant was part of exchange networks connecting the Mississippian world with cacao-growing regions. The research was conducted by Adam King and colleagues and published as “Cacao in the Mississippian World: Archaeogenomic evidence for T. cacao consumption at the Etowah Site, Georgia.”
