Easter Island’s Ancient Population Never Faced Ecological Collapse, Suggests Another Study

In the southern Pacific Ocean, far off the coast of Chile, lies the remote island of Rapa Nui, or Easter Island. Since the 1700s, when European explorers first reached its shores, Western anthropologists developed a theory about ‘ecological collapse,’ claiming the Rapanui people had depleted the island of resources and caused their own demise. The story has become a popular way to warn about the risk of resource overconsumption.

Now, a new study published in the journal Nature last week adds to a growing body of research showing this population collapse might have never happened. The finding supports a study published in June that suggested the island’s population didn’t crash, but rather was small to begin with.

The latest DNA analysis “serves as the final nail in the coffin of this collapse narrative,” says Kathrin Nägele, an archaeogeneticist at the Max Planck Institute for Evolutionary Anthropology who wrote a commentary accompanying the study, according to Nature News’ Ewen Callaway. “It’s correcting the image of Indigenous people.”

Located more than 2,000 miles from the South American continent, Rapa Nui is known for its large stone statues called moai. According to the ‘ecocide’ theory, the Rapanui people used up all their resources to move and build these statues, depleting the island of its native animals and vegetation.

In the new study, researchers worked closely with representatives of the Rapanui community to reconstruct the genomic history of its people. The international team of experts analyzed the genomes of 15 Rapanui who lived between 1670 and 1950. The remains of these people had been kept in a museum in Paris.

If the population had indeed collapsed, researchers would’ve seen a reduction in genetic diversity, according to the paper. But this wasn’t the case.

“Our genetic analysis shows a stably growing population from the 13th century through to European contact in the 18th century,” study author Bárbara Sousa da Mota, a physicist at the University of Lausanne in Switzerland, tells the Agence France-Presse. “This stability is critical, because it directly contradicts the idea of a dramatic pre-contact population collapse.”

The researchers behind the study published in June reached a similar conclusion through a different method. Previous research indicated that roughly 12 percent of Rapa Nui could have been covered with rock gardens, an agricultural method that involves adding rocks to the soil to maintain moisture and nutrients. The team used satellite images to map out rock gardens on the island to better understand how many people were actually living there historically.

Their findings revealed that only a small percent of the island—less than one-third of a square mile—was used for rock gardening. Such a low amount of agriculture could have supported about 4,000 people—nowhere near the approximately 15,000 people initially thought to have lived on the island.

The fact that both studies arrived at the same conclusion “shows the importance of looking at the same scientific question from different disciplines,” Sousa da Mota tells the Agence France-Presse.

In the new study, the genome analysis also provided insight into other people the Rapanui may have encountered. The island’s ancient inhabitants carried about 10 percent Native American ancestry in their genomes. This genetic mixing may have occurred sometime between 1250 and 1430, suggesting Polynesians may have reached the Americas before Europeans did.

It won’t come as a surprise to Polynesians that the Rapanui made it to the Americas, says Keolu Fox, a genome scientist at the University of California San Diego who was not involved with the research, to Nature News. “We’re confirming something we already knew,” he tells the publication. “Do you think that a community that found things like Hawaii or Tahiti would miss a whole continent?”

The Rapanui community today was deeply involved in the research, as they wanted to understand whether the collapse narrative was true, as the study’s lead author Víctor Moreno-Mayar, a geneticist at the University of Copenhagen, tells Science’s Rodrigo Pérez-Ortega.

Now, the ancient Rapanui remains are to be returned to the island from the museum in Paris, Moreno-Mayar adds.

“Recovering all ancestors is the priority,” Gabriela Atallah Leiva, a curator at the MAPSE Rapa Nui Museum in Hanga Roa, the island’s main town, tells Science. “For the Rapanui culture, the ancestors are here among us… they are not in the past, they are here in the present.”

Alexa Robles-Gil | | READ MORE

Alexa Robles-Gil is a bilingual science journalist based in New York City. Her work has appeared in the Guardian, Undark, Inside Climate News and more.