Based on detailed studies of the statues found along prehistoric roads, archaeologists Terry Hunt and Carl Lipo have shown that the pattern of breakage, form and position of statues is consistent with an "upright" hypothesis for transportation. Hunt and Lipo argue that when the statues were carved at a quarry, the sculptors left their bases wide and curved along the front edge. They showed that statues along the road have a center of mass that causes the statue to lean forward. As the statue tilts forward, it rocks sideways along its curved front edge and takes a "step." Large flakes are seen broken off of the sides of the bases. They argue that once the statue was "walked" down the road and installed in the landscape, the wide and curved base was carved down. All of this evidence points to an upright transportation practice.
