Although there is some uncertainty about dates, it now seems that Easter Island was first discovered by a small group of Polynesians sometime between 400 and 700
ad. The striking surprise that emerged from analysis of core samples is that Easter Island was at this time covered by a dense forest of Jubaea chilensis (the Chilean wine palm). This particular palm is a large, slow-growing tree that grows in temperate climates.
Following first discovery of Easter Island, the new inhabitants developed an economy based on the wine palm. Harvested trees were the raw material for canoes that could be used for fishing, leading to an early diet that depended very heavily on fish, gradually supplemented from other sources, including yams grown on deforested sections of the island, and domestic fowl. The population grew steadily and the civilization grew more sophisticated, allowing a substantial diversion of labor into ceremonial and other nonsubsistence activity. However, as time progressed, the forest stock gradually diminished. At first, liberation of forested land for agricultural uses, for dwelling space, and for other purposes would have been seen as a benefit. The rate of forest decline was slow. In a typical lifetime (somewhere between 30 and 40 years for those who survived early childhood), it would have been hard to notice a dramatic change in the forest cover because the stock would not have declined by more than about 5 or 6% over a 30- to 40-year period, until relatively near the end of viable forest.