Analysis of skulls in the oldest known cemetery in the South Pacific suggests that the earliest inhabitants of Vanuatu may have descended from Asian and Polynesian populations, while modern residents share more physical similarities with people in Melanesia.

The cemetery, on Vanuatu’s Efate Island, is 3,000 years old, and the skeletons of the earliest settlers, the Lapita, were discovered there in 2004. Australian researchers compared the Lapita skulls to those of living adults in Vanuatu and other parts of Polynesia and Melanesia, and concluded that the cranial structure was closer to that of present-day Polynesians and Asians.

Yet the current inhabitants of Vanuatu resemble Melanesians, said Matthew Spriggs, an archaeologist at the Australian National University and one of the study’s authors.

He and his colleagues speculate that Melanesians arrived in the area 2,800 to 3,000 years ago, intermarrying with the Lapita. There was little interaction with populations outside the region after that period, Dr. Spriggs said.