The results of a recent study challenge the common myth that ancient gardening practices of Easter Islanders caused a catastrophic population "collapse."
Easter Island (Rapa Nui), also known as Easter Island, has long been held up as an example of how over-exploitation of limited resources can cause catastrophic population collapse, environmental devastation, and the destruction of a culture through internal strife.
The theory suggests that hundreds of years ago, farmers on the South Pacific island practiced an agriculture that relied on cutting down palm trees at an unsustainable rate to create gardens, harvest fuel, and move statues, which led to disaster.
According to popular legend, the islanders were so focused on rock gardening (an ancient agricultural technique also known as rock mulching), erecting hundreds of giant stone statues, that their civilization collapsed.
When Europeans discovered Easter Island in 1722, they found a society living within its means, growing much of its food in rocky orchards in an otherwise uncultivable landscape, leading to the assumption that the population was much smaller than it had been before that date due to an "ecocide" that had brought the island's population down.
However, the new study offers a completely opposite theory: Easter Island is a story of how an isolated people created a sustainable system, allowing a small, stable population to flourish for centuries until the first contact with European colonial powers in the early 18th century.
The paper, published in the journal Science Advances, explains: “A vital element of this narrative is that the rapid rise and fall in population growth rates in the Easter Island region was driven by the construction and overexploitation of large-scale rock gardens. However, the scale of rock gardening is island-wide.” "Although it is fundamental to understanding food systems and demography, it needs to be better understood."
Contrary to popular belief that rock gardening was bad for the soil, the study says the practice “enhanced plant productivity by increasing available soil nutrients and conserving soil moisture.”
“Given the benefits of rock gardening in increasing soil productivity, and thus plant growth, its practice was a vital part of Easter Island life. Nearly half of the island’s diet consisted of terrestrial foods,” the research paper states.
The researchers used shortwave infrared (SWIR) satellite imagery and machine learning to determine that Easter Island's population was likely smaller than previously claimed, challenging the myth that the island's population in 1722 was much smaller than it had been hundreds of years earlier.
The results found that using the updated estimate of the number of orchards, the researchers calculated that only about 3,901 people were living on Easter Island at the time of European contact, and not 17,000 people as estimated by previous studies.