WORLD IN WANDER : RESEARCH . 1.4

About 3,000 years ago, people on the eastern edge of Asia began sailing east, crossing thousands of miles of oceans to reach uninhabited islands.

Their descendants, some 2,000 years later, invented the double-hulled canoe to travel even further east, reaching places like Hawaii and Rapa Nui.

Archaeologists and anthropologists have long debated : Just how far did the Polynesians' canoes take them? Did they make it all the way to the Americas?

The results of a new study suggest that they did. Today, people on Rapa Nui, also known as Easter Island and four other Polynesian islands carry small amounts of DNA that they may have inherited from people who lived in Columbia about 800 years ago.

One explanation : Polynesians reached South America, and then, took South Americans onto their boats to voyage back out to sea.

This new report bolsters work that archaeologists and anthropologists have been doing for years. Previous genetic studies have also hinted that people on Rapa Nui had some ancient South American ancestry.

But the new study offers a more compelling case because the researchers looked at more than 800 people using a number of sophisticated new statistical tools.

''This is the most convincing evidence I've seen,'' said Lars Fehren Schmitz, an anthropological geneticist at the  University of California, Santa Cruz, who was not involved in the study.

The new study emerged from a decade-long project to create a map of the diversity in modern Latin Americans.

After Asians crossed the Bering Land Bridge 16,000 years ago, they spread across the Americas, reaching the southern tip of South America by 14,000 years ago.

Since then, the populations of Latin America have gained unique genetic mutations, which have gotten mixed as they have interbred.

When European colonists brought enslaved Africans to the region, the genetic landscape of Latin America changed yet again.

Andres Moreno Estrada, a geneticist, and his wife, Karla Sandoval, an anthropologist, have worked with indigenous populations in Latin America to understand their genetic makeup.

Because most genetic studies are based on people of European ancestry, variants that could be medically important to other populations are often overlooked.

Last year, for example, Dr. Estrada, Dr. Sandoval and their colleagues published a study on asthma.

They discovered mutations in a gene that put certain groups of Latin Americans at greater risk of developing the disease.

The honor and serving of the latest global operational research on Polynesian voyagers, and modern genetic makeup, continues to the remaining 3 parts. The World Students Society thanks author, Carl Zimmer.