15 Mar 07

A survey of wild and domestic pigs is forcing archaeologists to reconsider both the origins of the first Pacific colonists and the routes humans used to reach the remote Pacific. Scientists from the University of Oxford and Durham University have revealed that ancient human colonists may have originated in Vietnam, not Taiwan or Island Southeast Asia (which includes Malaysia, the Philippines, Singapore and Indonesia) as established models of human migration suggest.

'Pigs are good swimmers, but not good enough to reach Hawaii,' said Greger Larson, who performed the genetic work while at the University of Oxford. 'Given the distances between islands, pigs must have been transported and so they give reliable evidence of human movement.' A report of the study into DNA and tooth shape in modern and ancient pigs is published this week in the Proceedings of the National Academy of Sciences USA. Using mitochondrial DNA obtained from modern and ancient pigs across East Asia and the Pacific, the research demonstrates that modern and ancient pigs on several Pacific islands share a common genetic heritage with Vietnamese wild boar, modern feral pigs on the islands of Sumatra, Java and New Guinea and ancient Lapita pigs in Near Oceania.

The new study contradicts longstanding ideas that the ancestors of Pacific islanders originated in Taiwan or Island Southeast Asia and travelled along routes that pass through the Philippines as they dispersed into the remote Pacific. Instead, the study suggests that ancient human colonists may have originated in Vietnam and travelled between numerous islands before first reaching New Guinea, and later landing on Hawaii and French Polynesia.

Greger Larson commented: 'Our data show that the accepted models detailing the routes people took to reach the Pacific need to be reconsidered. By studying the DNA of pigs we have opened a new window onto the history of human colonisation of the Pacific.' This study is part of an ongoing research project based at the University of Durham.