The giant stone statues in Polynesia's Easter Island may have just been "walked" out of quarry, according to a controversial new theory on how the monolithic human figures were transported to every corner of the island.
In a piece of experimental archaeology, a team of local and U.S. researchers showed that the massive statues, known as moai, can be moved from side to side by a small number of people, just as one might move a fridge.
"We constructed a precise three-dimensional 4.35 metric ton replica of an actual statue and demonstrated how positioning the center of mass allowed it to fall forward and rock from side to side causing it to 'walk,'" Carl Lipo, an archaeologist at California State University, Long Beach, and colleagues wrote in the Journal of Archaeological Science.
Nearly 1,000 huge statues stand on the remote Rapa Nui, the indigenous name of Easter Island. With sizes ranging from about 6 to 33 feet in height, the rock effiges feature human-like figures ending at the top of the thighs with large heads, long ears and pursed lips.
Scholars have long debated how the multi-ton statues were moved from the quarry in Rano Raraku, an extinct volcano where they were carved, throughout the island's rugged terrain.
Claims ranged from extra-terrestrial intervention to molding in situ. However, most archaeologists agree that the colossal stone statues were moved by rolling them on logs. In doing so, the statue-obsessed Rapa Nui people would have depleted the island of its forests.
But according to Lipo's team, new evidence challenges the "longstanding notions of 'ecocide' and population collapse before European contact."
The researchers looked at the statues that were successfully placed on platforms on the island's perimeter, and others that the islanders abandoned on road sides in an apparently random fashion.
According to Lipo, the position of the incomplete road moai shows that they fell over from upright positions, contradicting the theory that they were horizontally rolled on logs.
"The majority of statues are found facedown when the road slopes downhill, and often on their backs when going uphill," he said.
To test the walking hypothesis, Lipo and colleagues built a 4.35-ton concrete statue, which they say is a "precise proportionally scaled replica of an actual road moai shaped appropriately for transport."
Then they tested its upright movement at Kualoa Ranch in Hawaii.
Chanting "heave-ho," a team of 18 people managed to get the statue walking using three hemp ropes.
One was tied from behind near the top of the head at the eyes to keep the statue from falling on its face. The other two, tied to the same location at the eyes, were stretched on either side and pulled in alternating fashion to rock the statue.
"Each roll caused the statue to take a step," Lipo said. In under an hour, the statue traveled 100 meters.
"In contrast to popular notions of sledges, rollers or sliders of trees, the evidence shows that moai were specifically engineered to 'walk' in an upright position achieved using only ropes, human labor and simple cleared pathways," wrote the researchers.
They noted that material for ropes was abundant on the island since they were made from a woody shrub. Therefore, "statue making and transport cannot be linked to deforestation," they said.
"Multiple lines of evidence, including the ingenious engineering to 'walk' statues, point to Easter Island as a remarkable history of success in a most unlikely place," they concluded.
This story was provided by Discovery News.
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