Easter Island is famous for its giant stone statues – moai, created 800 years ago. Scientists have grappled with the mystery of their origins for decades, theorizing about their cultural significance and how the islanders carved and transported the statues weighing up to 92 tons. Portal arstechnica.com speak of a theory that can put everything in its right place.
Archaeologist Carl Lipo from Binghamton University suggests that the statues were transported in an upright position: with the help of workers and ropes, the moai “walked” to their pedestals. The oral traditions of the indigenous people of Easter Island mention stories of walking statues from the quarry – for example, in the song about the ancestors who created the walking moai statues.
Lipo's simple field tests in 2012 showed that such manipulations using ropes were practically possible, but his hypothesis also caused a lot of criticism in the scientific community. The moai on which the experiment was performed was relatively small – its mass was only 5 tons. There are many more statues on Easter Island, not to mention their number: how did a handful of islanders manage to transport so many heavy monuments from the quarry?
To get to the bottom of the mystery, the archaeological team compiled a database of the Moai. Of the 962 statues, 62 are located along roadsides – perhaps they were abandoned on their way to the pedestal where they were originally supposed to stand. Furthermore, moai standing near roads had a base much wider than shoulder width, which reduced the center of gravity and allowed the statue to walk without falling. But statues fixed on pedestals, on the contrary, have shoulders that are wider than the base.
Additionally, roadside moai are tilted at an angle of 6 to 16 degrees, which moves the center of mass closer to the front edge of the foundation. According to Lipo, this is a resourceful technical solution that further facilitates the statue's transportation. Leaning forward causes the moai to fall forward in a horizontal roll and each such movement becomes a step.
For these reasons, archaeologists believe that the stone carvers modified the statues upon reaching the pedestal by grinding the foundations to prevent them from tilting in a static position. The center of mass moves higher for a stable vertical position. The moai on the road don't even have carved eye sockets where the white coral eyes should be – they were probably decorated after the statue was installed on the pedestal.
Lipo and his team repeated the experiment – they assembled a replica of one of the moai statues on this road and tried to transport it by road. In total, 18 people using four ropes were able to move the statue forward 100 meters in just 40 minutes. As a result, real statues could easily be moved many kilometers over weeks by as many as 20-50 people – approximately the same number of members as large families on Easter Island.
The Binghamton archaeologist is not the first to test the walking hypothesis. Czech experimental archaeologist Pavel Pavel conducted similar experiments in the 1980s. His team was able to demonstrate something resembling a staircase of statues, but he concluded that 16 people and a leader were not enough to transport the statues. True, Paul's experience did not lead to widespread acceptance of the hypothesis – moving the Moai required too much effort, not to mention the fact that friction would damage the statue's foundations.
Finally, Lipo and his colleagues also studied the roads, finding that they were unsuitable for moving monuments horizontally using wooden rollers or other structures. But the characteristic sunken shape of the path will only help the walking method – it allows you to stabilize the slope during vertical transportation. Furthermore, the distribution pattern of the roads is very plausible, based on the theory that the roadside moai statues were abandoned due to mechanical malfunctions.
