Made by aboriginal sculptures have indicated, the inhabitants, where was located the sources of drinking water.
The statue is dated 1250-1500 years. Most of the statues are located around the perimeter of the island.
Before that, it was assumed that the statues had a ritual significance. To solve the mystery, scientists have been able, by comparing hydrological data about the sources of fresh water on the island with the location of the statues. In the end, it turned out that the location of the statues is almost identical to the sources.
Scientists have noted that the statues are located near the sources, and where there are none, no statues.