Rapa Nui (Easter Island)

Eight hundred and eighty-seven statues

The Rapa Nui carved 887 moai stone statues over a period of about six hundred years, from approximately AD 1100 to 1700.

The largest unfinished statue still attached to the bedrock of the Rano Raraku quarry would have stood 21 metres tall and weighed 270 tonnes. The largest one actually erected weighs 82 tonnes.

Each statue was carved from the soft volcanic tuff of the Rano Raraku crater quarry on the eastern side of the island, then somehow transported up to 18 kilometres across rough volcanic terrain to its final platform (ahu) site near the coast.

How they moved

For two centuries Western archaeologists assumed the statues had been moved horizontally on log rollers, with the loss of the island's palm forest cited as the consequence.

Rapa Nui oral tradition, however, consistently stated that the statues walked to their platforms.

In 2012 the American archaeologist Terry Hunt and the Hawaiian archaeologist Carl Lipo experimentally proved this. A team of 18 people, using only three ropes attached to a five-tonne moai replica, rocked the statue from side to side while tipping it forward, "walking" it a hundred metres in less than an hour.

The moai had been designed to walk. The centre of gravity was offset forward. The base was carved at an angle. The Rapa Nui oral tradition was literal historical memory, not metaphor.

Why their eyes were added last

The standing moai had distinctive white coral eyes inlaid with black obsidian or red volcanic scoria pupils, fitted into the empty stone sockets carved with the face.

The eyes were always added after the statue had been transported to its final ahu and raised upright. Never before. Without eyes the moai were considered inactive — simply rock. Once the eyes were inserted, the statue was "live" and the spirit of the ancestor it represented could see and protect the village.

Most of the eyes were dismantled during the period of inter-clan warfare on the island in the seventeenth and eighteenth centuries. One nearly complete pair was recovered from sand near Anakena beach in 1978.

A collapse story that wasn't

The popular story of Rapa Nui collapse — runaway population growth, deforestation for moai-rollers, "ecocide" — was popularised by Jared Diamond's book Collapse in 2005.

Recent archaeology has challenged most of it.

The population was probably not as large as Diamond claimed. The deforestation was caused by introduced rats consuming palm-tree seeds rather than by overuse for log rollers (the statues walked). And the population decline coincided with first European contact in 1722 and the diseases the Europeans brought.

The collapse, when it came, was external rather than self- inflicted.