Off the mark
But not everyone is convinced by Lipo and Hunt's work. “What they did was a stunt and not an experiment,” says Jo Anne Van Tilburg, director of the Easter Island Statue Project at the University of California, Los Angeles.
The shape of the team's model statue is not an accurate facsimile of the moai, she says, so any conclusions drawn from it are irrelevant. “What this work has done is disengaged the statues from the archaeological context, and I think any time you do that, you enter, however gingerly, into fantasy and speculation on a level that isn’t scientific," says Van Tilburg, whose own team has demonstrated that moai can be moved horizontally along logs (see video).
Yet aspects of the statues’ design seem intended for walking, contends Lipo. Their centre of mass is centered vertically and horizontally, but sits slightly forward of centre on the front-to-back axis, making it easy to rock the statues back and forth. Furthermore, the statues' relatively broad bodies and elongated heads make them stable when walking. “What’s cool is that their shape really reflects the engineering of the Rapa Nui people. They built these things to do this,” says Lipo.