1 No one knows for certain how the statues were transported by the islanders, most of whom lived far away from where the stones were． 2 It was impossible for men to carry the large stone statues, several of which were too heavy． 3 People doubt that they were dragged over the land, which is too rough． 4 Some people think that the islanders used large strong wooden tools, but there is not enough evidence to prove this． 5 The wood for making the tools should come from big trees, which did not exist on the island．