Sunday, January 27, 2008

Polynesian "express train" backed by genetics

A new study of the history of Polynesians and their ancestors suggest the predecessors to modern Polynesians were perhaps better at leaving their culture than their genes in places they stopped.

(Photo: A wet sail aboard Hawaiian voyaging canoe Hōkūle'a.)

The new work also appears to back up the thought that Polynesians tended to move on when they came across other cultures, and stay when they were the first inhabitants of a new land.

The new genetic study was done on DNA samples from nearly 1,000 Pacific Islanders from 41 Pacific populations. It indicates that the voyaging ancestors of today's Polynesians left Taiwan or an island nearby, passed fairly quickly through Melanesia, and then swept into the vast unpopulated central and eastern Pacific.

The work shows pre-Polynesian genetic links to the present-day inhabitants of the Melanesian islands—which include the Solomons, New Guinea and the Bismarck Archipelago—are comparatively weak.

“The Genetic Structure of Pacific Islanders,” was published in the Public Library of Science's journal, PloS Genetics. The authors are biological anthropologist Jonathan S. Friedlaender of Temple University and an international team of collaborators, including, Françoise R. Friedlaender, Floyd A. Reed, Kenneth K. Kidd, Judith R. Kidd, Geoffrey K. Chambers, Rodney A. Lea, Jun-Hun Loo, George Koki, Jason A. Hodgson, D. Andrew Merriwether, and James L. Weber.

The Polynesian languages, like Samoan, Hawaiian, Tahitian and New Zealand Maori, are part of a larger group of related tongues called Austronesian, which may have their roots among the aboriginal people of Taiwan thousands of years ago.

“The distribution and relations of Pacific language families reflect ancient settlement. Austronesian is a widespread and clearly defined linguistic family with more than 1,000 member languages, which has its greatest diversity, and likely origin, in Taiwan (about) 4,000–5,000 years ago,” the authors write.

About 3,300 years ago, once open-ocean sailing had been developed, these folks moved out from Taiwan, and during a stay in the Bismarck Archipelago, they developed into what became known as the Lapita People, whose best-known artifact is carefully decorated pottery.

But these were a voyaging people, and they soon voyaged again.

“After only a few hundred years, 'Lapita People' from this area had colonized the islands in Remote Oceania as far east as Tonga and Samoa, where Polynesian culture then developed,” the authors wrote.

The Friedlaender paper says that while these voyagers left significant parts of their language and culture in the Melanesian islands at which they stopped, that culture was “grafted” onto existing genetic populations and wasn't associated with wholesale genetic mixing.

“Our study suggests that in the Pacific, and specifically in Near Oceania, there is only a modest association between language and genetic affiliation. Oceanic languages were introduced and dispersed around the islands within the last 3,300 years, but there was apparently only a small infusion of accompanying 'Austronesian' ancestry that has survived,” the paper says.

The Friedlaender work argues strongly for the Express Train theory of the population of the Pacific. A rival theory, the Entangled Bank, suggests that there was so much movement and interaction that it would be impossible to clearly identify the ancestors to Polynesians. Another rival theory, the “Slow Boat to Polynesia,” says the Polynesian people sprang out of long-existing Melanesian populations.

The Express Train, by contrast, argues that the early voyagers moved fairly quickly from what is now Taiwan, through Melanesia and then onward into the rest of the Pacific.

The Friedlaender paper says its genetic results pretty much resolve the issue in favor of the Express Train, although it concedes that more research could more closely link the ancestral home to other islands of Southeast Asia than just Taiwan.

“Polynesians are closely related to Asian/Taiwanese Aboriginal populations, while they are very weakly associated with any Melanesian groups (the closest association there appears to be with New Ireland populations),” the paper says.

See a copy of the paper at

For students of Polynesia, there are intriguing links between these studies at the western end of Polynesia and recent studies at the eastern end. There, DNA work on chicken bones found in Chile showed that these South American chickens had came across the Pacific, and were closely related to the chickens of the Polynesians.

Previously, researchers had noted that sweet potatoes, an American crop, had somehow become established throughout Polynesia.

It's indirect evidence that the famed Pacific navigators visited the Americas and perhaps conducted trade. But to date, there's no evidence they stayed. Genetic studies have not to date shown any evidence of Polynesian DNA in the inhabitants of South America.

Polynesians of the voyaging millenia, one might say, were guests who were careful not to wear out their welcome.

© 2007 Jan W. TenBruggencate