Geography and Demography

The islands of Oceania are divided into three large geographic areas. Polynesia occupies an enormous triangle in the eastern and central Pacific, stretching from Hawaii in the north, to French Polynesia and Easter Island in the east, to New Zealand in the west. Melanesia encompasses the western island chains that lie south of the equator and extend from New Guinea to New Caledonia and Fiji. Micronesia includes the groups of islands that lie west of Polynesia and north of Melanesia. Although Polynesia is spread widely across the Pacific, the physical environments – whether volcanic high islands or coral atolls – are all quite similar in being lushly vegetated and almost all rich in food resources from land and sea. Melanesia has the greatest variety of physical environments: mountain rain forests, grassy plateaus, gorges and valleys, low jungles and alluvial plains, mosquito-ridden riverine and coastal swamps, sandy beaches, volcanic fields, and earthquake-prone rifts. In western Micronesia, weathered volcanic islands are interspersed among small, lush coral atolls. Farther to the east (Marshall Islands and Kiribati), the Micronesian atolls are generally much drier and larger. Except for temperate New Zealand and arid or temperate Australia, the climate of Oceania remains generally hot and humid year-round. It is generally accepted that Oceania and Australia were populated by waves of immigrants initially from Southeast Asia (Oliver 1962; Howe 1984; Marshall 1984). In fact, it was over 30,000 years ago that Southeast Asian hunter-gatherers crossed land bridges and narrow channels into New Guinea, Australia, and Tasmania. Intermigration among these landmasses was curtailed around 8,000 years ago, when New Guinea and Tasmania became separate islands.