caribbean research

Ancient DNA offers insights into the peopling of the Caribbean

Photo credit: Tom Björklund
By A&S News

Photo credit: Tom Björklund

Ancient DNA offers insights into the peopling of the Caribbean

By A&S News
New study reveals multiple waves of settlement and connections to the American mainland.

Today, the Caribbean, one of the last regions of the Americas to be settled by humans, is known for its diversity. But a new international study published in the journal Science shows that the islands were settled thousands of years ago by successive, diverse populations originating from the mainlands of the Americas.

“One of the things that we celebrate about the contemporary Caribbean is its diversity of peoples and cultures, but traditional archaeological understandings of the region have underplayed, or even denied, the time depth of this phenomenon,” said Will Pestle, associate professor at the University of Miami Department of Anthropology and a co-author of the study. “This research shows us that in the past, as in the present, the islands were made up of a rich variety of people from different points of origin.”

Using ancient DNA samples, the team of archaeologists and geneticists from the Caribbean, Europe, and North America found evidence of at least three population dispersals that brought people to the islands.

“The new data gives us a fascinating glimpse of the early migration history of the Caribbean,” said Hannes Schroeder, associate professor at the University of Copenhagen Globe Institute, and one of the senior authors of the study. “We find evidence that the islands were settled and resettled several times from different parts of the American mainland.”

More data, more details
The researchers used bone fragments excavated by Caribbean archaeologists from 16 archaeological sites across the region to analyse the genomes of 93 ancient Caribbean islanders. Due to the region’s warm climate, the DNA samples from people who lived between 400 and 3,200 years ago, were not well preserved.

But using so-called targeted enrichment techniques, the researchers managed to extract enough information from the remains to document at least three different population dispersals into the region: two earlier dispersals into the western Caribbean, one of which seems to be linked to earlier population dispersals in North America, and a third, more recent “wave,” which originated in South America.

“This study shows the value of genetic analysis as a complementary technique in the archaeological toolkit for understanding the deep history of a region like the Caribbean,” Pestle said. “The analysis of artifacts and sites tells us part of the story—about where people lived, what they ate, the tools they used—but these kinds of studies allow us insights into the biological histories of the region that artifact-based studies just can’t.”

Connections across the Caribbean Sea
Although researchers say it is not entirely clear how the early settlers reached the islands, there is growing archaeological evidence indicating that, far from being a barrier, the Caribbean Sea served as a kind of “aquatic highway” that connected the islands to the mainland and each other.

“Big bodies of water are traditionally considered barriers for humans and ancient fisher, hunter, gatherer communities are usually not perceived as great seafarers,” said Kathrin Nägele, a Ph.D. student at the Max Planck Institute for the Science of Human History and one of the first authors of the study. “Our results continue to challenge that view, as they suggest that there was repeated interaction between the islands and the mainland.

The researchers also found genetic differences between the early settlers and the newcomers from South America who, according to archaeological evidence, entered the region around 2,800 years ago.

The study was funded by the Max Planck Society, the European Research Council, and the Social Sciences and Humanities Research Council of Canada and conducted in the context of the ERC Synergy Project Nexus1492 and the SSHRC Project on Cuban Population Diversity.