Maize and farming technology may have arrived with people moving into the Maya region from the south thousands of years ago, the New York Times reports.
A team of researchers analyzed samples found preserved in two rock shelters in Belize, including ancient DNA from individuals who lived between 3,700 years and 9,600 years ago. As they report in Nature Communications this week, Harvard Medical School's David Reich and his colleagues generated genome-wide data from 20 individuals whose remains were excavated from the shelters and identified three distinct groups. One group lived there between 7,300 and 9,600 years ago and were descended from an Early Holocene Native American lineage and are only distantly related to present-day Mesoamericans. Another group lived there 3,700 years to 5,600 years ago and had ancestry related to both the previous group as well as a group related to the Chibchan populations of southern Central America and northern South America. The third group included modern-day Maya people.
The researchers suggest that a previously unknown migration from the south to the north led to the population change between the first two groups. The Times adds that Chibchan speakers may have moved northward, bringing maize and agricultural knowledge with them, in contrast to previous assumptions that farming knowledge spread throughout the Americas independently of people.