Easter Island is famous for its giant monumental statues, called moai, built some 800 years ago and typically mounted on platforms called ahu. Scholars have puzzled over the moai on Easter Island for decades, pondering their cultural significance, as well as how a Stone Age culture managed to carve and transport statues weighing as much as 92 tons. One hypothesis, championed by archaeologist Carl Lipo of Binghamton University, among others, is that the statues were transported in a vertical position, with workers using ropes to essentially "walk" the moai onto their platforms.
The oral traditions of the people of Rapa Nui certainly include references to the moai "walking" from the quarry to their platforms, such as a song that tells of an early ancestor who made the statues walk. While there have been rudimentary field tests showing it might have been possible, the hypothesis has also generated a fair amount of criticism. So Lipo has co-authored a new paper published in the Journal of Archaeological Science offering fresh experimental evidence of "walking" moai, based on 3D modeling of the physics and new field tests to recreate that motion.
The first Europeans arrived in the 17th century and found only a few thousand inhabitants on the tiny island (just 14 by 7 miles across) thousands of miles away from any other land. In order to explain the presence of so many moai, the assumption has been that the island was once home to tens of thousands of people. But Lipo thought perhaps the feat could be accomplished with fewer workers. In 2012, Lipo and his colleague, Terry Hunt of the University of Arizona, showed that you could transport a 10-foot, 5-ton moai a few hundred yards with just 18 people and three strong ropes by employing a rocking motion.
In 2018, Lipo followed up with an intriguing hypothesis for how the islanders placed red hats on top of some moai; those can weigh up to 13 tons. He suggested the inhabitants used ropes to roll the hats up a ramp. Lipo and his team later concluded (based on quantitative spatial modeling) that the islanders likely chose the statues' locations based on the availability of fresh water sources, per a 2019 paper in PLOS One.