Melanesians are an ethnic group in Melanesia. The original inhabitants of the group of islands now named Melanesia were likely the ancestors of the present-day Papuan-speaking people. They appear to have occupied these islands as far east as the main islands in the Solomon Islands, including Makira and possibly the smaller islands farther to the east.
It was particularly along the north coast of New Guinea and in the islands north and east of New Guinea that the Austronesian people came into contact with these preexisting populations of Papuan-speaking peoples, probably around 4,000 years ago. There was probably a long period of interaction that resulted in many complex changes in genetics, languages, and culture.
It was once postulated that from this area a very small group of people (speaking an Austronesian language) departed to the east and became the forebears of the Polynesian people. This theory was, however, contradicted by a study published by Temple University finding that Polynesians and Micronesians have little genetic relation to Melanesians; instead, they found significant distinctions between groups living within the Melanesian islands. Genome scans show Polynesians have little genetic relationship to Melanesians.
Some recent studies suggest that all humans outside of Africa have inherited some genes from Neanderthals, and that Melanesians are the only known modern humans whose prehistoric ancestors interbred with the Denisova hominin, sharing 4%–6% of their genome with this ancient cousin of the Neanderthal.
In the world, blond hair is exceptionally rare outside Europe. However, Melanesians of some islands are one of the few non-European peoples and the only dark-skinned group of humans known to have blond hair. This has been traced to an allele of TYRP1 unique to these people.
Predominantly Melanesian areas include the Mollucas of Eastern Indonesia, the New Guinea and surrounding islands, the Solomon Islands, Vanuatu and Fiji. The region New Caledonia and nearby Loyalty Islands for most of its history has had a majority Melanesian population, but its proportion has dropped to slightly below half in the face of immigration over the last century to present time. The largest and most populous Melanesian country is Papua New Guinea. The largest city in Melanesia is Port Moresby in Papua New Guinea with about 300,000 people, mostly of Melanesian ancestry.