As Halloween partygoers prepare to enjoy chocolate, a new study by an international research team, including the University of British Columbia, is pushing back the origins of the delicious sweet treats.
The study, published online today in Nature Ecology & Evolution suggests that cocoa ̵
Archaeological evidence for the use of cocoa dating back 3,900 years ago earlier suggested that the cocoa tree was first domesticated in Central America. But genetic evidence showing that the largest variety of cocoa tree and allied species actually occurs in equatorial South America – where cocoa is important to today's indigenous groups – prompted the UBC team and their colleagues to gather evidence for the plant at an archaeological site Place to look in the region.
"This new study shows us that people in the upper Amazon basin, reaching as far as the foothills of the Andes in southeastern Ecuador, harvest and consume cocoa, which seems to be a close relative of the Amazon. A type of cocoa, later in Mexico was used – and they did 1500 years earlier, "said Michael Blake, study co-author and professor in the UBC anthropology department. "They also used elaborate pottery older than the pottery found in Central America and Mexico, suggesting that the use of cocoa, probably as a drink, was something that was spreading north from cocoa farmers to what is now Colombia and finally, Panama and other parts of Central America and Southern Mexico. "
Theobroma cocoa, known as the cocoa tree, was a culturally important crop in pre-Columbian Mesoamerica – a historic region and cultural area in North America that spans from roughly Central Mexico via Belize , Guatemala, El Salvador, Honduras, Nicaragua and North Costa Rica. Cocoa beans have been used both as a means of payment and for use in drinks and rituals.
For the study, the researchers studied ceramic artefacts from Santa Ana-La Florida in Ecuador, the earliest known site of the Mayo-Chinchipe culture, which was occupied at least 5450 years ago.
The researchers used three lines of evidence that Mayo-chinchipe culture used cocoa between 5,300 and 2,100 years: the presence of starch granules specific to the cocoa tree in ceramic pots and broken pieces of ceramics; Remnants of theobromine, a bitter alkaloid found in the cacao tree, but not its wild relatives; and fragments of old DNA with sequences that are unique to the cacao tree.
The results suggest that Mayo chinchipe people domesticated the cacao tree at least 1500 years before harvest in Central America. With some of the artifacts of Santa Ana-La Florida connected to the Pacific coast, researchers suggest that trade in goods, including culturally important plants, would have enabled the journey of cocoa to the north.
Sonia Zarrillo, lead author and assistant to the study professor at the University of Calgary, who has done some research as a session teacher at the Department of Anthropology of UBC Okanagan, said the results represent a methodological innovation in anthropological research.
"For the first time, three independent lines of archaeological evidence have documented the presence of ancient cocoa in America: starch granules, chemical biomarkers, and ancient DNA sequences," she said. "These three methods combine to definitively identify a plant that is otherwise hard to find in archaeological records, as seeds and other parts are rapidly degraded in humid and warm tropical environments."
Discover the Origins of Food Today We Need "This is important because it helps us to understand the complex history of who we are today," Blake said.
"Today, we all rely on food created by the indigenous peoples of America," Blake said. "And one of the world's favorites is chocolate."
The cocoa analysis indicates the beginning of domesticated chocolate trees 3,600 years ago
Sonia Zarrillo et al, The Use and Domestication of Theobroma cacao during the Middle Holocene in the Upper Amazon Nature Ecology & Evolution (2018). DOI: 10.1038 / s41559-018-0697-x