From The New York Times:
In a recent study published in The Journal of Archaeological Science, Carl Lipo of Binghamton University and Terry Hunt of the University of Arizona demonstrated a plausible technique for how the statues were moved. Fourteen years ago, the researchers’ 18-person crew shimmied a 4.35-ton concrete replica over a 328-foot distance in just 40 minutes by using ropes attached to the sculpture’s head, causing it to rock and shift its weight from side to side with each tug, gradually advancing it forward. This experiment called into question existing theories about moai transport and reinforced ones proposed in Dr. Lipo and Dr. Hunt’s 2011 book “The Statues That Walked: Unraveling the Mystery of Easter Island.” Dr. Lipo said that the constant rocking and shifting of the moai over time wore down and contoured the prepared paths.