Sailors of Melanesia in the Pacific Ocean, 1846.
The limit of this ancient migration was Sahul, the continent formed when Australia and New Guinea were united by a land bridge as a result of low sea levels. The first migration into Sahul came over 40,000 years ago. A further expansion into the eastern islands of Melanesia came much later, probably between 4000 B.C. and 3000 B.C.
Particularly along the north coast of New Guinea and in the islands north and east of New Guinea, the Austronesian people, who had migrated into the area somewhat more than 3,000 years ago, came into contact with these pre-existing populations of Papuan-speaking peoples. In the late 20th century, some scholars theorized a long period of interaction, which resulted in many complex changes in genetics, languages, and culture among the peoples.
A Melanesian child from Vanuatu.
This Polynesian theory, however, is contradicted by the findings of a genetic study published by Temple University in 2008. It found that neither Polynesians nor Micronesians have much genetic relation to Melanesians. It appeared that, having developed their sailing outrigger canoes, the ancestors of the Polynesians migrated from East Asia, moved through the Melanesian area quickly on their way, and kept going to eastern areas, where they settled. They left little genetic evidence in Melanesia.
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