Next to its sheer size, the profound isolation of its many small islands is the most distinctive feature of the Pacific Ocean. Over 25,000 islands are scattered across the surface of the Pacific, more than in all the other oceans combined, but their land area adds up to little more than 125,000 square kilometers, about the size of New York State, and their inhabitants total less than two million people, about a quarter of the number that live in New York City. The oceanic islands of the Pacific are some of the most isolated places on Earth. Many are uninhabitable, by virtue of their small size and particular characteristics, but even the most favored are very isolated fragments of land, strictly circumscribed by the ocean, strictly limited in terms of the numbers of people they can support. This basic fact of environmental circumstance has been the most pervasive influence in determining the social arrangements and cultural practices of the people that settled in thePacific Islands.
The peopling of the Pacific Islands has been described as the greatest feat of maritime colonization in human history. Contrary to the conclusions of Thor Heyerdahl's Kon-Tiki expedition of 1946, the evidence of plant dispersal, archaeology, linguistics, and genetics now shows quite conclusively that the Pacific Islands were not populated from the east by South Americans who drifted on balsa-wood rafts and the prevailing wind and current, but from the west, by groups from mainland Asia who gradually spread from island to island out into the Pacific. The process began over 40,000 years ago and reached Easter Island—the most isolated place on Earth—about 1,500 years ago. It ended about 1,000 years ago, when people first settled in Hawaii and New Zealand.
Simply surviving those ocean crossings of indeterminate length, in open canoes, to arrive on the shores of uninhabited and hitherto unknown islands, was a formidable achievement. But having found an oasis of land in a watery wilderness, crossed its reef, and landed on its shores, the survivors then faced a series of pressing problems for which solutions had to be found quickly if the small group was to become a vigorous, self-sustaining island population.