Easter Island, home of the enormous statues called moai, is a tiny dot of volcanic matter in the South Pacific Ocean. Called by Chileans the Isla de Pascua, Easter Island is known as Rapanui by its inhabitants, today primarily newcomers from Chile and the Polynesian islands.
Original Settlement of Easter Island
Genetic research has shown that Easter Island was settled by about 40 Polynesians, who landed on the island ~700 AD and went on, undisturbed, for several centuries. During that time, the population grew, reaching a total population of perhaps some 10,000 at its height, ca 1000 AD. The original Easter Islanders were hunters and fishers, relying on the large variety of birds that made the island, covered at the time with a lush palm tree forest, their home.
The most striking feature of the island are the moai, over 900 large stone statues or megaliths of faces, between 6 and 33 feet high. Construction of the moai is thought to have begun ~AD 1000-1100 and ended ~AD 1680. Each was carved out of the Rano Raraku quarry, a volcanic crater on Rapanui. More than 300 unfinished moai are still in place there-the largest unfinished statue at Rano Raruku is over 60 feet tall. Moai were moved by the islanders distances of up to 10 miles to prepared sites all over the island, set upright and decorated with inlaid coral eyes and a 'pukao', a hat of red scoria.
Ecological Disaster at Easter Island
The feverish construction of the moai apparently caused the breakdown of the society. The palm tree forest was cut down for housing and to allow agricultural fields, but primarily, it must be said, to move the enormous moai into place. As the palm trees and shrubs disappeared-18 different plant species went extinct-the birds left, and without palm trees to build canoes, the people were unable to fish. According to dated pollen core samples from an interior lake, the sharpest decline (90%) took place ca 1150-1165 cal AD. After that, the society apparently devolved to warfare, as evidenced by human skeletal remains showing the effects of violence and the presence of stone tool weapons about 1100 AD and increasing over time. The violence was also aimed at the moai, with many of them toppled and broken. The last of the trees were gone ~1475-1500 AD.
- In The Statues that Walked, however, researchers Hunt and Lip argue that moai construction actually made it possible for the Rapanui to survive in the face of nearly impossible odds.
- Read the review of The Statues that Walked
The records of the rise and fall of Easter Island's population are found in the archaeological remnants of the society: the pollen, skeletal remains, and other elements show that the survivors of the violence were able to adapt to the crisis and rebuilt a system of agriculture based on sweet potatoes and sugar cane. By the time the Dutch landed in 1722, however, the society had recovered and rebuilt peaceful farming communities with a population of about 3,000.
But the Dutch and British brought syphilis with them, devastating the population. In 1866, Peruvian kidnappers took half the remaining population away and enslaved them. A year later, they brought 15 survivors back to the island, some of whom had contracted smallpox. By 1872, there were no more than 110 descendants of the original inhabitants of Easter Island.
Agriculture on Easter Island
Horticulture was being practiced on the island by AD 1300, evidenced by the remains of house gardens, horticultural fields and chicken houses. Crops were tended or grown in a mixed-crop, dryland production systems, growing yams, sweet potatoes, bottle gourd, sugar cane, taro and bananas. "Lithic mulch" was used to increase soil fertility; rock walls and stone circle planting pits helped protect the crops from wind and rain erosion as the deforestation cycle continued.
A recent stable isotope research on human teeth for from burials ranging the entire habitation of the island (Commendador and colleagues) indicates that terrestrial sources (rats, chickens and plants) were the primary source of food throughout the occupation, with marine sources becoming an important part of diets only after 1600 AD.
Easter Island Archaeology
Ongoing archaeological research about Easter Island concerns the reasons for the environmental degradation and the end of the society about 1500 AD. One study argues that a colonization of the island by the Pacific rat (Rattus exulans) may have exacerbated the end of the palm trees; another says that climatic changes had an effect on the agricultural stability of the economy.
The dating of all events at Easter Island is under debate as well, with some researchers arguing the original colonization took place later, or that the birds and palm trees were gone as early as AD 900. Most argue that the major deforestation took place over a period of about 200 years; which 200 years seem to be the biggest question.
The precise manner in which the moai were transported across the island-dragged horizontally or walked upright-has also been debated. Both methods have been tried experimentally and were successful in erecting moai.
Building Easter Island Statues
The statues on Rapa Nui were built from a variety of materials, but primarily volcanic tuff from two quarries, the Puna Pao quarry and the much larger Rano Rakaru quarry. The ahu--the platforms upon which the statues were erected--were painstakingly constructed from beach boulders and dressed flow lava stone walling.
- Read more about the Rano Rakaru Quarry
See the photo essay Moai in their Landscape for more images and information
This article is a part of the About.com guide to the Climate Change and Archaeology.
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