Researchers believe they may have finally solved the mystery of how the ancient people of Easter Island, or Rapa Nui, were able to move massive stone hats and place them on top of statues with little effort and resources.
Investigators from Binghamton University, State University at New York believe that the ancient people may have used a ‘parbuckling’ technique to move the massive stones.
Some of them weighed up to 12 tons and were moved all around the island, across long distances, with few people and resources.
The ancient people of Easter Island, or Rapa Nui, were able to move massive stone hats and place them on top of statues with little effort and resources
‘Of the many questions that surround the island’s past, two tend to stand out: How did people of the past move such massive statues (moai) and how did they place such massive stone hats (pukao) on top of their heads?,’ said Carl Lipo, a professor of anthropology at Binghamton University.
Pukao are cylinders made of red scoria, a dark volcanic rock.
‘We’ve learned they moved the statues in a walking fashion using simple, physics-based processes, in a way that was elegant and remarkably effective,’ said Lipo.
‘Our latest study now tackles the issue of the hats (pukao)’
‘These multi-ton stone objects were carved at a separate quarry, transported across the island and somehow raised to the top of the heads of the statues,’ he added.
Parbuckling works by wrapping a line around the puako, and then using a large ramp to pull it up to the top of the platform, requiring minimal effort.
The researchers used photographs of different pukao and were able to generate 3D models that showed details of the most likely method of their transportation.
Researchers said this use of resources shows how efficiently the people of Easter Island used their resources, which contrasts with previously beliefs
The researchers used photographs of different pukao and were able to generate 3D models that showed details of the most likely method of their transportation
‘The number of possible pukao emplacement methods is limited only by the human imagination,’ said Sean Hixon, lead author and current graduate student at Penn State University.
‘Examples of past ideas for pukao transport include sliding the pukao up a wooden ramp or gradually building a pile of stones beneath the pukao’
‘The challenge is to move beyond merely possible transport methods and to identify a transport scenario that is consistent with variation in the archaeological record’
‘We expect that part of the shapes of pukao will reflect the physical constraints associated with transport’ said Hixon.
‘Different possible transport methods constrain aspects of pukao variability in different ways.’
The researchers discovered the pukao were most likely rolled from the quarry to the moai, and then rolled up the ramps.
Parbuckling works by wrapping a line around the puako, and then using a large ramp to pull it up to the top of the platform, requiring minimal effort
‘In parbuckling, a line would have been wrapped around the pukao cylinder, and then people would have pulled the rope from the top of the platform,’ said Lipo.
‘This approach minimizes the effort needed to roll the statue up the ramp. Like the way in which the statues were transported, parbuckling was a simple and elegant solution that required minimum resources and effort.’
The researchers believe that this use of resources showed how efficient the ancient people were, in contrast to previous studies.
‘Easter Island is often treated as a place where prehistoric people acted irrationally, and that this behavior led to a catastrophic ecological collapse,’ said Lipo.
‘The archaeological evidence, however, shows us that this picture is deeply flawed and badly misrepresents what people did on the island, and how they were able to succeed on a tiny and remote place for over 500 years.’
The researchers believe that this use of resources showed how efficient the ancient people were, in contrast to previous studies
‘Our analysis of pukao adds significantly to this new understanding of the island: Rapa Nui people made remarkable achievements through their ingenuity’, Lipo added.
Monument construction, such as the pukao, played a ‘vital role’ in their society, the researchers said.
‘While the social systems of Rapa Nui do not look much like the way our contemporary society functions, these were quite sophisticated people who were well-tuned to the requirements of living on this island and used their resources wisely to maximize their achievements and provide long-term stability,’ Lipo noted.