Within about 500 years, Polynesian voyagers had created settlements across a vast part of the Pacific Ocean. Now, DNA is helping researchers trace their routes.
"The colonization of eastern Polynesia was a remarkable event in which a vast area, some one-third of the planet, became inhabited by humans in ... a relatively short period of time," said archeologist Carl Lipo of New York's Binghamton University. Indeed, settling this area of the world was a huge milestone in human history. And now, recent research is revealing more details about that time.
Computational biologist Alexander Ioannidis of Stanford University, population geneticist Andres Moreno-Estrada of the National Laboratory of Genomics for Biodiversity in Mexico, and their associates have been hard at work studying DNA across east Polynesia for a better idea of what early settlers were up to.
The research team studied DNA parts that were solely of Polynesian origin in over 400 individuals alive today. The participants came from 21 populations in the Pacific islands. So how did studying today's residents give insight into the past? According to the study, island-specific genetic fingerprints allowed the researchers to sketch up settlement paths. Rises in rare genes that likely came from a group hopping from one area to another and led to more people having the rare variants helped the team build a settlement trail.
By comparing shared DNA between people on different islands, the researchers predicted when certain settlements were built. As for the actual path the researchers carved? According to the data, early settlers likely left from Samoa in western Polynesia and went south, then east, reaching the Cook Islands around 830. A couple of hundred years later, some of those who went farther east to the Tuamotus ended up settling in Easter Island and other areas in eastern Polynesia.
Making things even more interesting, those who ventured from Tuamotu to other islands constructed huge stone statues wherever they went. It was long thought that indigenous people from Tuamotu were responsible for the structures, and the recent study seems to confirm that. The results are "consistent with the [statue] carving tradition arising once in a single point of common origin, likely the Tuamotu islands," explained Andres Moreno-Estrada.
You can read the full study in Nature here.