The new findings paint a more complicated and deeper picture of humans’ relationship with cacao, one of the world’s biggest economic crops to date. “The story of cacao is a rich story, of the history of a plant that in its domestic form is a gift to the world from the people who transformed it through generations of labor and careful tending,” says Michael Blake, an anthropologist at the University of British Columbia in Vancouver and a coauthor of the new study. “This story can be repeated with an almost endless list of foods and materials that the world takes for granted today, but whose origins we seldom know much about and rarely appreciate.” Blake and his team his team sought to reconcile that fact with what the archeological evidence was saying, and they got lucky. The new discovery hinges on the analysis of ceramic artifacts found in the Santa Ana-La Florida archeological site in present-day Ecuador, home to some of the earliest signs of the Mayo-Chinchipe culture that lived in the area nearly 5,450 years ago. Blake and his team thought the artifacts may have been used as vessels for cocoa drinks, but nobody had ever looked into it. The team used three lines of testing to characterize the artifacts and find evidence of cacao domestication: the presence of theobromine (a major compound in domestic cacao but not in its wild relatives, which creates similar effects to caffeine); the presence of preserved particles of starch from cacao trees; and the positive identification of old DNA fragments specific to cacao. There’s enough theobromine and ancient DNA in the samples to show cacao presence wasn’t incidental, but part of routine customs. One of the artifacts testing positive for cacao was dated to between 5,310 and 5,440 years old. “All these facts tend to demonstrate that cacao was really domesticated and used in their everyday life by Mayo Chinchipe people and not simply used opportunistically,” says Claire Lanaud, a researcher at the French Agricultural Research Centre for International Development and a coauthor of the study. Cameron McNeil, a researcher at Lehman College in New York who was not involved in the study, doesn’t think the new findings are particularly surprising, but she does find them interesting for “turning back the date of cacao use by more than a thousand years, and that they demonstrate that South Americans were using the seeds as well as the pulp. Many scholars have proposed that it was the people of lower Central America, or Mesoamerica, who first used the seeds in beverages.” Juan Carlos Motamayor, an agricultural engineer at Universal Genetic Solutions who has previously studied cacao domestication through genetic analysis and was not involved with the study, believes the results “provide convincing evidence” that early use of cacao occurred in Ecuador. “This is extremely interesting,” he says, “because it would support the hypothesis that trading and knowledge of the cocoa bean was possible at the time to facilitate the movement to Mesoamerica where it was intensively domesticated.” However, it’s important to recognize evidence of usage does not necessarily equate to evidence of outright domestication of cacao. “For example,” says Motamayor, “if we find residues of lingonberries in ancient pottery from Native Americans of the Pacific Northwest, does that mean that this fruit was domesticated by them? Lingonberry is still an undomesticated fruit.” Blake acknowledges this limitation, and his team hopes to incorporate greater genetic analysis as a part of their follow-up investigations into other collections of excavated pottery. “It is very exciting for archaeologists, anthropologists, and historians to find the actual evidence of ancient activities and practices that help us fill in the gaps in our knowledge, more fully tracing the details of our human past,” he says. And as we cram our faces with chocolate treats this Halloween, we can take comfort in the knowledge that our species’ love of the stuff extends far back into our history.
