Easter Island environmental degradation was due to colonial intruders not ecocide

See Island at the End of the World’ Review: Faces of Rapa Nui: European explorers landed on Easter Island in the 18th century. Disease and emigration soon followed by Adam Kuper. He is a fellow of the British Academy. He reviewed the book Island at the Edge of the World: The Forgotten History of Easter Island by Mike Pitts. Excerpt:

"Mr. Pitts summarizes the new apocalyptic parable that emerged: “Society collapsed in a fit of war and cannibalism.” Some commentators, such as Jared Diamond, the author of the popular “Guns, Germs, and Steel” (1997), saw a deeper meaning: Could this be our own future if we don’t take care?

Scientists have since established that the degradation of the island was in fact gradual, taking centuries, caused largely by drought, volcanic eruptions and the arrival of the Polynesian rat. Ancient skeletons show no sign of injuries due to war or cannibalism. Mr. Pitts dismisses this ecocide narrative and places the blame for environmental degradation where it belongs: with colonial intruders."

Related posts:

The Mysterious 'Ecocide' Collapse of Easter Island Never Really Happened 

The truth about Easter Island: a sustainable society has been falsely blamed for its own demise 

Was Easter Island (Rapa Nui) The Victim Of Ecocide? Maybe Not 

Resilience, not collapse: What the Easter Island myth gets wrong

New evidence upends contentious Easter Island theory, scientists say 

New evidence upends contentious Easter Island theory, scientists say

By Katie Hunt of CNN.

"Rapa Nui, also known as Easter Island, never experienced a ruinous population collapse, according to an analysis of ancient DNA from 15 former inhabitants of the remote island in the Pacific Ocean.

The analysis also suggested that inhabitants of the island, which lies about 3,700 kilometers (2,300 miles) from the South American mainland, reached the Americas in the 1300s — long before Christopher Columbus’ 1492 landing in the New World. 

Settled by Polynesian seafarers 800 years ago, Rapa Nui, today part of Chile, has hundreds of monumental stone heads that echo of the past. The island has long been a place of intrigue.  

Some experts, such as geographer Jared Diamond in his 2005 book, “Collapse,” used Easter Island as a cautionary tale of how the exploitation of limited resources can result in catastrophic population decline, ecological devastation and the destruction of a society through infighting.

But that theory remains contentious, and other archaeological evidence suggests that Rapa Nui was home to a small but sustainable society.

The new analysis marks the first time scientists have used ancient DNA to address the question of whether Easter Island saw a self-inflicted societal collapse, helping to shed light on its mysterious past.

Easter Island genomes

To investigate Rapa Nui’s history further, researchers sequenced the genomes of 15 former residents who lived on the island during the past 400 years. The remains are stored at the Musée de l’Homme, or Museum of Mankind, in Paris, which is part of the French National Museum of Natural History.

The researchers found no evidence of a genetic bottleneck corresponding to a steep drop in population, according to the study that published Wednesday in the scientific journal Nature. 

Instead, the island was home to a small population that steadily increased in size until the 1860s, the analysis suggested. At this point, the study noted, slave raiders from Peru forcibly removed one-third of the island’s population.

“There is definitely not a strong population collapse, like it has been argued, a population collapse where 80% of the population or 90% of the population died,” said study coauthor J. Víctor Moreno-Mayar, an assistant professor of geogenetics at the University of Copenhagen’s Globe Institute in Denmark.

The genomes also revealed that the Easter Islanders had exchanged genes with a Native American population, suggesting that the inhabitants crossed the ocean to South America somewhere between 1250 and 1430, ahead of Columbus’ arrival in the Americas — and well before Europeans reached Rapa Nui in 1722.

Around 6% to 11% of the individuals’ genomes can be traced to coastal South American ancestors, the study found, and the team’s analysis provided information about when these two groups met and had offspring. The authors estimated it took place 15 to 17 generations before that of the individuals studied.

Polynesian seafarers

The finding is not totally surprising. Oral histories and analysis of the DNA of present-day islanders suggested such ancestry, and remains of sweet potato, an import from South America, have been found on the island predating European contact, Moreno-Mayar said.

Some experts, and the wider public, have been reluctant to let go of cataclysmic stories about Easter Island, said Lisa Matisoo-Smith, a professor of biological anthropology at New Zealand’s University of Otago.

But the ancient genomes add to a growing body of evidence that the idea of a self-inflicted population collapse on Easter Island is a false narrative, said Matisoo-Smith, who wasn’t involved in the study.

“We know that the original Polynesian voyagers who discovered and settled Rapa Nui at least 800 years ago were among the greatest navigators and voyagers in the world,” she said in a statement shared by New Zealand’s Science Media Centre.

“Their ancestors had spent at least 3000 years living in an Oceanic environment. They sailed eastwards across thousands of kilometres of open ocean and found almost all habitable islands across the vast Pacific. It would be more surprising if they had not reached the coast of South America. These results do provide some intriguing evidence of the timing of that contact.” 

Matisoo-Smith noted that scholars based in Pacific regions had questioned the narrative of ecocide and society collapse based on a range of archaeological evidence.

“But now, we finally have ancient DNA evidence that directly addresses these two questions and perhaps will allow us to focus on a more realistic narrative of the history of this intriguing, yet actually rather typical, Polynesian island,” she said.

A study published in June, based on satellite imagery of land once used to grow food, reached a similar conclusion."

Related posts:

The Mysterious 'Ecocide' Collapse of Easter Island Never Really Happened 

The truth about Easter Island: a sustainable society has been falsely blamed for its own demise 

Was Easter Island (Rapa Nui) The Victim Of Ecocide? Maybe Not 

Resilience, not collapse: What the Easter Island myth gets wrong

The Mysterious 'Ecocide' Collapse of Easter Island Never Really Happened

By Michelle Starr. Michelle Starr is a Senior Journalist at ScienceAlert.

"The people of Rapa Nui, or Easter Island, were not the instruments of their own demise, according to new research.

In a comprehensive new study, researchers found that the population of monument-carvers could not possibly have been big enough to collapse under the demands placed on their environment, as has previously been suggested.

The myth of this so-called Rapa Nui "ecocide" – held up for decades as a cautionary tale about overexploitation of natural resources – should be firmly relegated to the bin of outdated theories, scientists now say.

This finding is just the latest in a mounting body of evidence that the Pacific Islander population's decline had nothing to do with their way of living.

In fact, the collapse so soon after European contact in the 1700s probably had more to do with the slave trade, enforced migration, and introduced pathogens.

The finding was based on an analysis of the rock gardens found on Rapa Nui, in which the islanders grew their food.

A team led by archaeologist Dylan Davis of Columbia Climate School conducted a new satellite survey of the sites, and found that the number of these gardens could not have supported a population large enough to collapse under its own weight.

"This shows that the population could never have been as big as some of the previous estimates," Davis says.

"The lesson is the opposite of the collapse theory. People were able to be very resilient in the face of limited resources by modifying the environment in a way that helped."

According to the ecocide theory, popularized by American researcher and historian Jared Diamond, a population of thousands of Pacific Islanders once lived on Rapa Nui.

In Diamond's version of events, this native population cut down all the trees, which left the fertile soil vulnerable to erosion. This meant that they couldn't grow as much food, so they started starving, resorting to war, cannibalism, and, ultimately, collapse.

More and more, however, scientists have been discovering that the Rapa Nui people were a lot more resilient and resourceful than the collapse narrative suggests.

In addition to sweet potatoes grown in their rock gardens, the islanders ate seafood, and more evidence suggests that they were still there on the island living quite happily when the Europeans arrived.

However, previous satellite surveys of the rock gardens seemed to support the notion of a large population.

Of the 164 square kilometer (63 square mile) area of the island, as much as 21.1 square kilometers was devoted to gardens, these surveys found, supporting a possible population of up to 17,000 people – much higher than the 3,000 or so reported by the first European visitors.

Davis and his colleagues went about their survey in a highly methodical fashion, and found support for a different interpretation.

The island's rock gardens were built by strewing up to boulder-sized rocks over low ground that would have been more protected from wind erosion and salt spray from the ocean. In the gaps between the rocks, the islanders planted their crops.

This can be difficult to differentiate from just a normal field of rocks, particularly on a rocky island, so the researchers spent five years carefully surveying rock gardens on the ground, and cataloging their properties, such as higher levels of soil moisture and nitrogen.

They then trained a machine learning algorithm to identify these properties in satellite data recorded by short-wave infrared imaging.

"There are natural rock outcrops all over the place that had been misidentified as rock gardens in the past. The short-wave imagery gives a different picture," Davis says.

The results showed that only around 0.76 square kilometers of Rapa Nui were devoted to rock gardens, which alone could have supported a population of around 2,000 people.

Add other food sources – such as the seafood already mentioned, and other crops, such as bananas – and the island could only have sustained a population of around 3,000 people, the team thinks.

This matches the number found by the first Europeans in 1722, suggesting that the Rapa Nui people were living happily and sustainably at the time. By 1877, the population numbered just over 100. The arithmetic seems pretty straightforward here

"Our results help refine estimates of agricultural productivity, suggesting that previous estimates were between five and 20 times too high," the researchers write in their paper.

"This finding holds significant implications for estimates of population size and subsistence strategies of the Rapanui people before European contact."

In future research, the researchers plan to use the data to model the Rapa Nui population more comprehensively, giving us a new tool for understanding their society, and how it was destroyed.

The research has been published in Science Advances."

Related posts:

The truth about Easter Island: a sustainable society has been falsely blamed for its own demise 

Was Easter Island (Rapa Nui) The Victim Of Ecocide? Maybe Not 

Resilience, not collapse: What the Easter Island myth gets wrong

Resilience, not collapse: What the Easter Island myth gets wrong

By Jennifer Micale of SUNY-Binghamton.

"You probably know this story, or a version of it: On Easter Island, the people cut down every tree, perhaps to make fields for agriculture or to erect giant statues to honor their clans. This foolish decision led to a catastrophic collapse, with only a few thousand remaining to witness the first European boats landing on their remote shores in 1722.

But did the demographic collapse at the core of the Easter Island myth really happen? The answer, according to new research by Binghamton University anthropologists Robert DiNapoli and Carl Lipo, is no.

Their research, “Approximate Bayesian Computation of radiocarbon and paleoenvironmental record shows population resilience on Rapa Nui (Easter Island),” was recently published in the journal Nature Communications. Co-authors include Enrico Crema of the University of Cambridge, Timothy Rieth of the International Archaeological Research Institute and Terry Hunt of the University of Arizona.

Easter Island, or Rapa Nui in the native language, has long been a focus of scholarship into questions related to environmental collapse. But to resolve those questions, researchers first need to reconstruct the island’s population levels to ascertain whether such a collapse occurred and, if so, the scale.

“For Rapa Nui, a big part of scholarly and popular discussion about the island has centered around this idea that there was a demographic collapse, and that it’s correlated in time with climate changes and environmental changes,” explained DiNapoli, a postdoctoral research associate in environmental studies and anthropology.

Sometime after it was settled between the 12th to 13th centuries AD, the once-forested island was denuded of trees; most often, scholars point to human-prompted clearing for agriculture and the introduction of invasive species such as rats. These environmental changes, the argument goes, reduced the island’s carrying capacity and led to a demographic decline.

Additionally, around the year 1500, there was a climactic shift in the Southern Oscillation index; that shift led to a dryer climate on Rapa Nui.

“One argument is that changes in the environment had a negative impact. People see that there was a drought and said, ‘Well, the drought caused these changes,’” said Lipo, a professor of anthropology and environmental studies and associate dean of Harpur College. “There are changes. Their population changes and their environment changes; over time, the palm trees were lost and at the end, the climate got drier. But do those changes really explain what we’re seeing in the population data through the radiocarbon dating?”

Reconstructing population changes

Archaeologists have different ways to reconstruct population sizes using proxy measures, such as looking at the different ages of individuals at burial sites or counting ancient house sites. That latter measure can be problematic because it makes assumptions as to the number of people who live in each house, and whether the houses were occupied at the same time, DiNapoli said.

The most common technique, however, uses radiocarbon dating to track the extent of human activity during a moment in time, and extrapolating population changes from that data. But radiocarbon dates can be uncertain, DiNapoli acknowledged.

For the first time, DiNapoli and Lipo have presented a method that is able to both resolve these uncertainties and show how changes in population sizes relate to environmental variables over time.

Standard statistical methods don’t work when it comes to linking the radiocarbon data to environmental and climate changes, and the population shifts connected with them. To do so would involve estimating a “likelihood function,” which is currently difficult to compute. Approximate Bayesian Computation, however, is a form of statistical modeling that doesn’t require a likelihood function, and thus gives researchers a workaround, DiNapoli explained.

Using this technique, the researchers determined that the island experienced steady population growth from its initial settlement until European contact in 1722. After that date, two models show a possible population plateau, while another two models show possible decline.

In short, there is no evidence that the islanders used the now-vanished palm trees for food, a key point of many collapse myths. Current research shows that deforestation was prolonged and didn’t result in catastrophic erosion; the trees were ultimately replaced by gardens mulched with stone that increased agricultural productivity. During times of drought, the people may have relied on freshwater coastal seeps.

Construction of the moai statues, considered by some to be a contributing factor of collapse, actually continued even after European arrival.

In short, the island never had more than a few thousand people prior to European contact, and their numbers were increasing rather than dwindling, their research shows.

“Those resilience strategies were very successful, despite the fact that the climate got drier,” Lipo said. “They are a really good case for resiliency and sustainability.”

Burying the myth

Why, then, does the popular narrative of Easter Island’s collapse persist? It likely has less to do with the ancient Rapa Nui people than ourselves, Lipo explained.

The concept that changes in the environment affect human populations began to take off in the 1960s, Lipo said. Over time, that focus became more intense, as researchers began to consider changes in the environment as a primary driver of cultural shifts and transformations.

But this correlation may derive more from modern concerns with industrialization-driven pollution and climate change, rather than archaeological evidence. Environmental changes, Lipo points out, occur on different time scales and in different magnitudes. How human communities respond to these changes varies.

Take a classic example of the overexploitation of resources: the collapse of the cod fisheries in the American Northeast. While the economies of individual communities may have collapsed, larger harvesting efforts simply switched to the other side of the world.

On an isolated island, however, sustainability is a matter of the community’s very survival and resources tend to be managed conservatively. A misstep in resource management could lead to tangible, catastrophic consequences, such as starvation.

“The consequences of your actions are immediately obvious to you, and everyone else around you,” Lipo said.

Lipo acknowledged that proponents of the Easter Island collapse story tend to see him as a climate-change denier; that’s emphatically not the case. But he cautioned that the ways ancient peoples dealt with climate and environmental changes aren’t necessarily reflective of current global crises and their impact in the modern world. In fact, they may have a good deal to teach us about resilience and sustainability.

“There’s a natural tendency to think that people in the past aren’t as smart as we are and that they somehow made all these mistakes, but it’s really the opposite,” Lipo said. “They produced offspring, and the success that created the present. Even though their technologies might be more simple than ours, there is so much to be learned about the context in which they were able to survive.”"

The truth about Easter Island: a sustainable society has been falsely blamed for its own demise

By Catrine Jarman. She is a PhD researcher in Archaeology and Anthropology, University of Bristol. Excerpt:

"The ecocide hypothesis centres on two major claims. First, that the island’s population was reduced from several tens of thousands in its heyday, to a diminutive 1,500-3,000 when Europeans first arrived in the early 18th century.

Second, that the palm trees that once covered the island were callously cut down by the Rapa Nui population to move statues. With no trees to anchor the soil, fertile land eroded away resulting in poor crop yields, while a lack of wood meant islanders couldn’t build canoes to access fish or move statues. This led to internecine warfare and, ultimately, cannibalism.

The question of population size is one we still cannot convincingly answer. Most archaeologists agree on estimates somewhere between 4,000 and 9,000 people, although a recent study looked at likely agricultural yields and suggested the island could have supported up to 15,000.

But there is no real evidence of a population decline prior to the first European contact in 1722. Ethnographic reports from the early 20th century provide oral histories of warfare between competing island groups. The anthropologist Thor Heyerdahl – most famous for crossing the Pacific in a traditional Inca boat – took these reports as evidence for a huge civil war that culminated in a battle of 1680, where the majority of one of the island’s tribes was killed. Obsidian flakes or “mata’a” littering the island have been interpreted as weapon fragments testifying to this violence.

However, recent research lead by Carl Lipo has shown that these were more likely domestic tools or implements used for ritual tasks. Surprisingly few of the human remains from the island show actual evidence of injury, just 2.5%, and most of those showed evidence of healing, meaning that attacks were not fatal. Crucially, there is no evidence, beyond historical word-of-mouth, of cannibalism. It’s debatable whether 20th century tales can really be considered reliable sources for 17th-century conflicts.

What really happened to the trees

More recently, a picture has emerged of a prehistoric population that was both successful and lived sustainably on the island up until European contact. It is generally agreed that Rapa Nui, once covered in large palm trees, was rapidly deforested soon after its initial colonisation around 1200 AD. Although micro-botanical evidence, such as pollen analysis, suggests the palm forest disappeared quickly, the human population may only have been partially to blame.

The earliest Polynesian colonisers brought with them another culprit, namely the Polynesian rat. It seems likely that rats ate both palm nuts and sapling trees, preventing the forests from growing back. But despite this deforestation, my own research on the diet of the prehistoric Rapanui found they consumed more seafood and were more sophisticated and adaptable farmers than previously thought.

Blame slavers – not lumberjacks

So what – if anything – happened to the native population for its numbers to dwindle and for statue carving to end? And what caused the reports of warfare and conflict in the early 20th century?

The real answer is more sinister. Throughout the 19th century, South American slave raids took away as much as half of the native population. By 1877, the Rapanui numbered just 111. Introduced disease, destruction of property and enforced migration by European traders further decimated the natives and lead to increased conflict among those remaining. Perhaps this, instead, was the warfare the ethnohistorical accounts refer to and what ultimately stopped the statue carving.

It had been thought that South Americans made contact with Rapa Nui centuries before the Europeans, as their DNA can be detected in modern native inhabitants. I have been involved in a new study, however, led by paleogeneticist Lars Fehren-Schmitz, which questions this timeline. We analysed Rapanui human remains dating to before and after European contact. Our work, published in the journal Current Biology, found no significant gene flow between South America and Easter Island before 1722. Instead, the considerable recent disruption to the island’s population may have impacted on modern DNA.

Perhaps, then, the takeaway from Rapa Nui should not be a story of ecocide and a Malthusian population collapse. Instead, it should be a lesson in how sparse evidence, a fixation with “mysteries”, and a collective amnesia for historic atrocities caused a sustainable and surprisingly well-adapted population to be falsely blamed for their own demise."

Was Easter Island (Rapa Nui) The Victim Of Ecocide? Maybe Not

Don't Blame the Natives: It was a rat that caused the sudden collapse of Easter Island's civilization CHARLES C. MANN, WSJ, 7-30-11. Excerpts:

"Rapa Nui once was much more rich and populous. Roggeveen had remarked on the island's lack of trees and speculated that it formerly had been heavily forested. As the island's population rose, the popular theory goes, its people cut down all the trees for slash-and-burn farming and as rollers to transport statues. With the forest gone, Rapa Nui's soil degraded; unable to feed themselves, Mr. Diamond argued in his best-selling "Collapse" (2005), Easter Islanders faced "starvation, a population crash, and a descent into cannibalism." The fall was abrupt and overwhelming; scores of giant statues were abandoned, half-finished. Roggeveen had discovered a ruin—and a powerful eco-parable. Books and articles by the hundred have pointed to Rapa Nui as the inevitable result of uncontrolled population growth, squandered resources and human fecklessness. "The person who felled the last tree could see it was the last tree," wrote Paul G. Bahn and John Flenley in "Easter Island, Earth Island" (1992). "But he (or she) still felled it." "The parallels between Easter Island and the whole modern world are chillingly obvious," Mr. Diamond proclaimed. "The clearest example of a society that destroyed itself by overexploiting its own resources," he said, Rapa Nui epitomizes "ecocide," presenting a stark image of "what may lie ahead of us in our own future." No, it doesn't, write archaeologists Terry Hunt and Carl Lipo in "The Statues That Walked," a fascinating entry in the pop-science genre of Everything You Know Is Wrong. Messrs. Hunt and Lipo had no intention of challenging Mr. Diamond when they began research on Rapa Nui. But in their fourth year of field work, they obtained radiocarbon dates from Anakena Beach, thought to be the island's oldest settlement. The dates strongly indicated that the first settlers appeared around A.D. 1200—eight centuries later than Heyerdahl and other researchers had thought. Wait a minute, the authors in effect said. Rapa Nui is so remote that researchers believe it must have been settled by a small group of adventurers—a few dozen people, brave or crazy, in boats. The new evidence suggested that their arrival had precipitated catastrophic deforestation "on the scale of decades, not centuries." The island then probably had only a few hundred inhabitants. Some ecologists estimate that the island originally had 16 million palm trees. How could so few people have cut down so much so fast? Puzzle piled upon puzzle. Why was there no evidence of "large-scale prehistoric farming"? Other Polynesian societies covered their land with miles of terraces. Easter Islanders, by contrast, "seemed to be underutilizing the island"—a contrast that "was all the more perplexing given the enormous amount of effort they had apparently put into making their massive statues and stone [plinths]." Rapa Nui's forest had been mainly composed of giant palms, which have soft, fibrous wood. Used as rollers, they would have been crushed by the load. No farming, no statue-schlepping—why would the islanders have removed the forest? The real culprit, according to "The Statues That Walked," was the Polynesian rat (Rattus exulans), which stowed away on the boats of the first Polynesian settlers. In laboratory settings, Polynesian rat populations can double in 47 days. Throw a breeding pair into an island with no predators and abundant food and arithmetic suggests the result: ratpocalypse. If the animals multiplied as they did in Hawaii, the authors calculate, Rapa Nui would quickly have housed between two and three million. Among the favorite food sources of R. exulans are tree seeds and tree sprouts. Humans surely cleared some of the forest, but the real damage would have come from the rats that prevented new growth. "Their success was short-lived. As Messrs. Hunt and Lipo point out, the 18th and 19th centuries were terrible times to reside in a small, almost defenseless Pacific nation. Rapa Nui was repeatedly ravaged by Peruvian slaving parties and nonnative diseases. In a 2007 article in Science, Mr. Diamond estimated that hundreds of laborers were needed to move the statues, suggesting that the eastern settlements of the island alone had to have "a population of thousands"—which in turn was proof of the island's destructive overpopulation. By showing that the statues could have been moved by much fewer people, Messrs. Hunt and Lipo have removed one of the main supports of the ecocide theory and the parable about humankind it tells."