Ancient DNA reveals diverse origins of Caribbean’s earliest inhabitants

Ancient DNA suggests early migrants to the Caribbean may have come from several places, including perhaps North America.

Tom Björklund

The Caribbean, which today includes a diverse mix of human cultures, was one of the last places in the Americas occupied by people. Yet researchers don’t know precisely where these early migrants came from when they arrived somewhere between 8000 and 5000 years ago. Now, ancient DNA suggests the deep history of the Caribbean includes complex tales of migration and mingling, including how descendants of the first waves of inhabitants interacted with newcomers who arrived beginning 2800 years ago.

“I’m thrilled to see the time span they were able to cover,” says Jada Benn Torres, a genetic anthropologist at Vanderbilt University who wasn’t involved in the new research. Genetic material decays quickly in tropical environments, she notes, and only a handful of genomes from precolonial Caribbean people had been sequenced prior to the new work.

Archaeologists divide precolonial Caribbean history into two eras: the Archaic Age, which includes the region’s early settlements and stretches back 8000 years on some islands, and the Ceramic Age, which began about 2800 years ago. In this latter age, an apparent wave of new arrivals from northern South America brought different styles of pottery and a lifestyle that depended more on agriculture to the islands, according to previous archaeological and genetic research.

But the origins of the Archaic Age peoples remained unclear. A team of mostly European and Caribbean researchers analyzed the DNA of 52 individuals from seven Archaic Age archaeological sites on Cuba, spanning from 3200 years ago to 700 years ago. They found evidence of at least two genetic groups, they report today in Science. That suggests these groups came from different places. “This is the first time that we can actually say that these [early inhabitants] were not only culturally diverse, but also biologically diverse,” says Yadira Chinique de Armas, an archaeologist at the University of Winnipeg and an author of the paper.

One individual showed a genetic similarity to Indigenous people who lived on California’s Channel Islands 5000 years ago, raising the possibility that some of the Caribbean’s earliest inhabitants may have originally hailed from North America or Central America. But researchers need additional genomes from ancient people who lived in places like Florida and Mexico’s Yucatán Peninsula to know for sure, says Kathrin Nägele, an archaeogeneticist at the Max Planck Institute for the Science of Human History and the paper’s first author.

Another big question is what happened when Archaic Age groups met the Ceramic Age newcomers after 2800 years ago. The Science paper found just one person, from Puerto Rico, who shows mixed Ceramic Age and Archaic Age admixture. Another paper on ancient DNA from the Caribbean, posted this week on bioRxiv, examined 184 early Caribbean inhabitants and found two people who had a mix of genes from both Ceramic Age and Archaic Age peoples. Both individuals lived on Hispaniola, the island that today includes Haiti and the Dominican Republic. It’s rare to see so little genetic mixing between groups once they meet, says Hannes Schroeder, an ancient DNA researcher at the University of Copenhagen. “We need more individuals from those crucial places in order to really have an idea as to how widespread [this genetic mixing] was.”

The studies are “both really novel contributions,” says Jorge Ulloa Hung, an archaeologist at the Museum of the Dominican Man and the Technological Institute of Santo Domingo in the Dominican Republic, who wasn’t involved in either one. Traditional models of Caribbean history, influenced by the views of European colonizers, erased the region’s complexity and diversity. But the new genetic work shows “the Caribbean was potentially always a mosaic” of cultures, origins, and ancestries.

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