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The statues on Easter Island are among the most mysterious objects made by humans.

We still don't know how they were moved, why they were placed at particular sites around

the island, and why they were made in the first place.

Now, researchers think they have at least some answers.

Because a new analysis finds that the statues are located near sources of fresh water.

The study appears in the journal, Plas I.

It's believed that the residents of Rappanui, the indigenous name for Easter Island,

began constructing these carvings in the 13th century.

The statues, called Moai, which sit upon stone platforms called Ahu, are the very definition of monumental.

Most weigh between 20 and 30 tons, and of the thousand on the island, about 400 have been moved from the quarry where they

originated and placed on Aahu located elsewhere.

But those Aahu locations aren't necessarily everywhere.

They're in some places and not in others.

And the questions that we started to ask ourselves was,

why do we find these Ahu and Malay some places on the landscape, but not others?

Carl Lipo, an anthropologist at Binghamton University in Central New York.

He says that most of these sculptures are found along the coast, but some are inland, and

they're not necessarily in obvious places. For example, we don't find Ahu and statues located on the tops of hills.

Places that we might expect to find them if these things were symbolic or representing ancestors

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