BY JONELL PANTLITZ
Humans settled in the Caribbean over 6,000 years ago and now three to four thousand years later, the history of the original Caribbean islanders has come into perspective with a new study that combines decades of archaeological work with advancements in genetic technology. An international team led by Harvard Medical School’s David Reich analysed the genomes of 263 individuals in the largest study of ancient human DNA in the Americas to date.
The U.S. Genetics traces two major migratory waves in the Caribbean by two distinct groups, thousands of years apart, revealing an archipelago populated by highly mobile people whose distant relatives often live on numerous islands.
Reich’s lab also developed a new genetic technique for estimating past population size, which showed the number of people living in the Caribbean when Europeans arrived was far less than previously thought; it is estimated to be about 10,000 to 50,000, rather than the million or more reported by Columbus and his successors.
Archaeologist William Keegan, whose work in the Caribbean spans for more than 40 years, confirms, “This moves our understanding of the Caribbean forward dramatically in one fell swoop,” said Keegan. “The methods David’s team developed helped address questions I didn’t even know we could address.”
Researchers extracted and analyzed DNA from 174 people who lived in the Caribbean and Venezuela between 400 and 3,100 years ago, combining the data with 89 previously sequenced individuals.
The team, which assisted in this study consisted of Caribbean-based scholars, who received permission to carry out the genetic analysis from local governments and cultural institutions, that acted as caretakers for the human remains. The authors also engaged representatives of Caribbean Indigenous communities in a discussion of their findings.
According to Keegan, “the genetic evidence offers new insights into the people of the Caribbean. The islands’ first inhabitants, a group of stone tool-users, boated to Cuba about 6,000 years ago, gradually expanding eastward to other islands during the region’s Archaic Age. Where they came from remains unclear – while they are more closely related to Central and South Americans than to North Americans, their genetics do not match any particular Indigenous group. However, similar artifacts found in Belize and Cuba may suggest a Central American origin.”
Approximately 2,500-3,000 years ago, farmers and potters related to the Arawak-speakers established a second pathway into the Caribbean. Using the fingers of South America’s Orinoco River Basin, they travelled from the interior to coastal Venezuela and pushed north into the Caribbean Sea, settling in Puerto Rico and eventually moving westward. Their arrival ushered in the region’s Ceramic Age. Over time, nearly all-genetic traces of Archaic Age people vanished, except for a holdout community in western Cuba that persisted as late as European arrival. Intermarriage between the two groups was rare, with only three individuals in the study showing mixed ancestry.
During the Ceramic Age, Caribbean pottery underwent at least five marked shifts in style over 2,000 years. Some archaeologists pointed to these transitions as evidence for new migrations to the islands. However, DNA tells a different story, suggesting all of the styles were developed by descendants of the people who arrived in the Caribbean 2,500-3,000 years ago, that they may have interacted and taken inspiration from.
Genetics even reveal family connections across islands. There was a study of male X chromosomes that uncovered nineteen pairs of “genetic cousins” living on different islands. These are people who share the same amount of DNA as biological cousins, but may be separated by generations. In the most striking example, one man was buried in the Bahamas while his relative was laid to rest about 600 miles away in the Dominican Republic.
All information in this article is reported from the Florida Museum. For more information visit www.floridamuseum.ufl.edu
