Archaeologists in Vanuatu have unearthed an ancient cemetery containing the headless skeletons of what are believed to be the earliest known ancestors of Pacific Islanders.
The 3000-year-old remains are those of the Lapita people, who colonised Vanuatu, New Caledonia, Fiji, Tonga and Samoa when the Pharaohs reigned in Egypt, says Professor Matthew Spriggs of the Australian National University, who led the dig.
He expects tests to confirm that the skeletons belong to the ancestors of Polynesian groups like Maori, Tongans and Samoans.
"Up until now people have speculated about the origins of the Polynesians, the origins of the Lapita people, and who were the Lapita people. We've actually got the Lapita people."
The Vanuatu National Museum asked the Australian university to investigate the site after it was disturbed by bulldozers clearing the way for a prawn farm. It was excavated in three stages over 2004, 2005 and 2006.
Professor Spriggs says the remains suggest the Lapita dug up dead people and removed their heads after burial and may have believed that children "weren't real people".
This is because not one child aged between 1 and 16 was found among the 70 skeletons at the cemetery at Teouma, on the southern coast of the island of Efate.
"Did they feel that kids weren't real people yet, so they were treated differently or weren't buried in the same place?"
Another mystery is the location of the heads.
Of 70 individuals, only seven skulls have been found, including three on one man's chest, three between the legs of another man and one in a pot.
Professor Spriggs says it is likely the heads were removed after burial.
He says the fact that skulls were found in groups of three suggests that the number may have had magical significance for the Lapita.
Until about 100 years ago when European missionaries arrived in the Pacific, it was common practice for islanders to let the flesh rot away from the head of a dead person and then place the skull in a shrine.
"The head was seen as the seat of the soul, so it's the most important part."
Professor Spriggs says scientists in New Zealand and American laboratories will test the bones for traces of ancient DNA which, together with skull measurements, may solve the riddle of the origins of the Polynesian people.
He says the tests are most likely to confirm theories that the Polynesians originally came from Southeast Asia via eastern Indonesia, the Philippines and ultimately Taiwan.