Researchers may have solved the mystery behind what caused the extinction of the Rapa Nui people of Easter Island.
Recent findings suggest significant changes in land use and dynamics that occured within the community before the European arrival may have been linked to the people's demise, the University of Auckland reported.
"The results of our research were really quite surprising to me. Indeed, in the past, we've published articles about how there was little evidence for pre-European-contact societal collapse," said study co-author Thegn Ladefoged of the School of Social Sciences in the Faculty of Arts.
To make their findings, the scientists looked at more than 400 obsidian artifacts from six sites around the island. Obsidian absorbs water after being exposed to air, allowing the team to measure the amount of water in the artifacts and determine how old they were. These findings helped the researchers determine land use and population fluctuations based on the number of tools made during each time period.
Sites on the northwest coast of the island showed an increase in population that occurred between 1220 and 1650 followed by a significant decline. The second site on the northwest coast (which was wetter and less prone to drought but had low soil fertility) saw an increase in use from 1200 to 1480 that sustained itself before declining around 1705. The third site, which was both rainy and fertile, showed an increase in use starting at 1250 and remaining consistent until about 1850.
Europeans are believed to have arrived on the island around the year 1722, but these findings suggest the indigenous was already struggling before this occurred.
"It is clear that people were reacting to regional environmental variation on the island before they were devastated by the introduction of European diseases and other historic processes," Professor Ladefoged concluded.
In the future the researchers plan to examine individual dwelling on the island in hopes of gaining further insight into the interaction between Easter Island's aboriginal people and the natural environment.
The findings were published in a recent edition of the Proceedings of the National Academy of Sciences .
