The First Settlers
The Melanesia region includes Papua New Guinea, Australia and the island chains to the east including Vanuatu, New Caledonia and Fiji. The word “Melanesian” is more of a geographical name than a description of an ethnic group, so its meaning in this context is somewhat vague. But, in general, the indigenous population of the region can be broken down into pre-Austronesian (including Papuans and Aboriginal Australians) and Austronesian.
As early as 50,000 years ago, the first modern humans made the narrow sea crossing from Southeast Asia to the Melanesia region after following the southern coastal route out of Africa. About 25,000 years ago, at the height of the last glacial period, Australia, Tasmania and Papua New Guinea were part of the same landmass, called Sahul. They were separated about 10,000 years ago, when melting glaciers caused the sea level to rise.
Papua New Guinea is one of the few places in the world where agriculture was developed locally, rather than being imported from elsewhere. But the wild plants available to the indigenous inhabitants did not lend themselves to intense cultivation. The main crop grown by the Papuans, prior to the arrival of sweet potatoes, was taro. Papua New Guinea is also home to more than 850 distinct languages, making it one of the most diverse countries in the world. Australia also once had hundreds of unique indigenous languages, particularly in the tropical northern regions, although most are now extinct.
Although the Aboriginal Australians aren't technically considered Melanesian, the groups that initially populated Papua New Guinea and Australia probably arrived from Southeast Asia at roughly the same time. There was some interaction among the Melanesians, Australians and other islanders in the area, but the Aboriginal Australians did not adopt agriculture to the same extent as most other Melanesians (possibly due to their harsher climate). With the exception of some tribes along the coast that relied more heavily on fishing, most Aboriginal tribes remained semi-nomadic hunter-gatherers until the arrival of Europeans in the 17th and 18th centuries.