During the middle period, ahus also contained burial chambers, and the images portrayed by moai are thought to have represented important figures that were deified after death.
The biggest statue found dating to the middle period measures about 32 feet tall, and consists of a single block weighing about 82 tons (74,500 kilograms).
In 1770, the Spanish viceroy of Peru sent an expedition to the island; the explorers spent four days ashore and estimated a native population of some 3,000 people.
Just four years later, the British navigator Sir James Cook arrived to find Easter Island’s population decimated by what seemed to have been a civil war, with only 600 to 700 men and fewer than 30 women remaining.
Between the early and middle periods, evidence has shown that many early statues were deliberately destroyed and rebuilt as the larger and heavier moai for which the island is most famous.
Easter Island’s most dramatic claim to fame is an array of almost 900 giant stone figures that date back many centuries.
The statues reveal their creators to be master craftsmen and engineers, and are distinctive among other stone sculptures found in Polynesian cultures.
It is still unknown precisely why these statues were constructed in such numbers and on such a scale, or how they were moved around the island.
Archaeological excavations of Easter Island reveal three distinct cultural phases: the early period (700-850 A.