Mongabay May 3, 2023. The Amazon Rainforest is often considered the ultimate wilderness. Here, nature rules ruthlessly in all its grandeur. There’s no room for agriculture here and, hence, none for humankind, except for a few small groups of hunter-gatherers. For many people across the globe, this would be their idea of the Amazon. However, recent archaeological research turns that image on its head.

Human presence in the world’s largest tropical rainforest is not only much older than previously thought, but also much more significant and varied than long presumed. Until the turn of the 21st century, the ruling paradigm was that the soil in the Amazon was too poor to support agriculture. And, without enough food, it’s not suited for humankind. Today, there’s little doubt among archaeologists that the Amazon was, in fact, a hotspot for plant cultivation.

Eduardo Neves is well-versed in this paradigm shift in Amazonian archaeology and its consequences on our view of the past, present and future of the rainforest. A professor of archaeology at the University of São Paulo, Brazil, he’s worked for more than 30 years in the central and southwest Amazon. He recently published his latest book, Sob os tempos do equinócio: Oito mil anos de história na Amazônia central (“Under the times of the equinox: 8,000 years of history in central Amazon,” not yet translated into English.)

    Archaeology in the Amazon is pretty unique, as we not only work with the past, but also with the present and the future,” says Neves, 56. “Even in Brazil, the dominant view still is that the ‘green hell’ of the Amazon does not allow for cultivation and civilization. But archaeology tells a different story. People can live and flourish in the Amazon, but only if they do so in a very different way than we do today.”

Mongabay: In the 16th century, Spanish priest Gaspar de Carvajal was among the first Europeans to sail down the Amazon River. Based on his journey, he published a manuscript describing seeing lots of people, towns, roads and agriculture. Yet, his book was long dismissed as a work of fiction. Why is that?

Eduardo Neves: There are several reasons. One is that Carvajal’s manuscript was only published in the late 19th century. It had long been forgotten in a library in Lima. By that time, naturalists and anthropologists had been working in the Amazon for about a century and had encountered very few people. They assumed what they saw was a reflection of the situation in the Amazon before the European conquest, not the result of colonialism. And so they thought people like Carvajal were wrong.

Another reason is that they compared the Amazon to other places in South America, such as the Inca civilization in the Andes or the Maya culture in Yucatán or Guatemala. There they saw monumental remains, while in the Amazon lowlands they saw nothing of the sort. The easiest way to explain this was to look at the environment: the rainforest, with its poor soil, did not allow for agriculture and therefore not for large populations and a complex culture.

What they overlooked was that the raw materials used for construction in the tropical lowlands were organic: wood, straw, fibers and soil. In the Andes it was stone. Due to the depopulation following the European conquest, which brought disease, war and slavery, all organic material disappeared. And with it all evidence of a human presence. Thus the image of a forest largely devoid of people came about. The paradigm only shifted at the turn of the 21st century. Today, we know that many features of the rainforest are in fact man-made.

Mongabay: But how does one research organic material to recreate an image of the past? Doesn’t organic material by definition just decay?

Eduardo Neves: That has to do with another recent shift in archaeology, a technical one. I have been doing archaeology for over 30 years, and I must say it has never been more interesting. Not just in the Amazon but everywhere. For example, if you look at plants, yes, they decay and decompose. Yet, microscopic parts will always remain, such as phytoliths and starch grains, the shape of which changes according to genus and species.

Isotopes, which are found in the bones of animals and humans, can show us what their diet was. Then we have DNA research these days, and the carbon-dating techniques we use today are much more accurate. Thanks to this technical shift, we are able to see things that were invisible until 20 years ago.

Mongabay: On May 25, 2022, the journal Nature published the stunning results of a German-led archaeological mission in the Bolivian Amazon. Using lidar remote-sensing technology, the team revealed settlements, stepped platforms and conical pyramids once part of the Casarabe culture (500-1400 C.E.) hidden under the canopy. Settlements were linked to each other by causeways several kilometers long. In addition, a massive water-management infrastructure, complete with canals and reservoirs, was uncovered. What is lidar, and are there plans to use it in Brazil? 

Eduardo Neves: I was actually on the helicopter doing the remote sensing [for that study]. The archaeologists in charge are friends of mine. Looking down, you see nothing but a sea of green. Lidar uses light from a laser to collect measurements. It fires hundreds of thousands of rays per second. Most bounce back from the canopy, others from the ground underneath. This allows you to measure the distance and create a topography very fast. It is really a revolution in archaeology, comparable to radio-carbon dating. The equipment is still very expensive, but we plan to use it later this year to map large areas of Rondônia state and the Xingu Basin in the southwest and south of the Brazilian Amazon.

Mongabay: Since the 1990s, the U.S.archaeologist Michael Heckenberger has worked in the Xingu. At first sight the region seemed to consist of pristine rainforest. But Heckenberger revealed there were actually clusters of interconnected settlements lying underneath. Linked by roads, the settlements were surrounded by palisades and ditches. He furthermore found evidence of agriculture, managed tropical forest areas and even fish farming. What makes Heckenberger’s work so important?

Eduardo Neves: Michael’s work is important for many reasons. For one, he was the first to talk about cities and urbanism in the Amazon in a serious way. Because the structures he found were so massive, he introduced the term “garden cities.” Also, Michael was the first to take the intellectual contribution of the Indigenous people seriously. He actually co-authored several academic pieces with the people he worked with. He truly believes that is the proper way forward. So, Michael is a pioneer in many ways.

Mongabay: Until 2009, you worked in the central Amazon around the city of Manaus for some 15 years. What were your main findings?

Eduardo Neves: There were archaeologists working in the central Amazon before us, but we were the first to bring large teams of 40 to 50 people into the field, which allowed us to describe sites chronologically and in greater detail. I think our main contribution to Amazonian archaeology has been to show that there was a great diversity in the history of the people living there. We unearthed large central plazas and earthworks, as well as very small living spaces. In general, there still is a very generic view of people living in the Amazon. One tends to forget the Amazon is larger than continental Europe. People in Sicily are not like people in Scandinavia. Likewise, there is a lot of cultural diversity in the Amazon. And there always has been.

Mongabay: How far back does evidence of human presence in the central Amazon date to?

Eduardo Neves: The oldest human presence we found dates back 8,500 years. But in other places in the Amazon the first signs of human occupation are even older. For example, the oldest known rock art in the Americas was found in the Colombian Amazon and dates back more than 12,000 years. In Brazil, we have the rock paintings of Monte Alegre, which date back almost 12,000 years. People have been living in the Amazon as early as anywhere else in the Americas. Yet, until the 1990s the dominant view was that people could not live in the tropical rainforest, as it does not allow for agriculture.

Mongabay: Since 2009 you’ve been working in the state of Rondônia in the western Amazon, which is all about agriculture. Can you tell us a bit more?

Eduardo Neves: I long worked in the central Amazon, which was fascinating, but there we encountered a gap in the sequence. For some reason we couldn’t find many sites dated between 8,000 and 3,000 years ago. At the same time, we noticed that the sites dated 3,000 years or younger showed clear evidence of people interacting with nature, changing the landscape, for example, through the use of dark soil [artificially enhanced, very fertile patches of soil that are found throughout the Amazon rainforest and that often have a greater proportion of edible species than the surrounding forest]. One question we had: was this an abrupt change? Or something that slowly changed over millennia? Thanks to previous archaeological surveys, we knew there was a history of more or less uninterrupted human occupation in the southwest Amazon dating back to 9,000 B.C.E. So that was one important reason to go to Rondônia.

In addition, genetic, not archaeological, research had shown that the southwest Amazon had the largest diversity in contemporary manioc. The assumption was that it was an early center of agrobiological domestication. We started looking for archaeological evidence to back up the hypothesis and we succeeded. We found early evidence of cultivation of, for example, manioc and peach palm, the only domesticated palm tree in the Amazon.

Mongabay: Did you find physical remains as well?

Eduardo Neves: We did. For instance, in one of the places where we worked we found an artificial shell mount, some 160 meters long and 6 meters high [525 by 20 feet]. When the region floods it becomes an island. It’s still occupied by Indigenous people today. They live nearby. Every year when the rains come, they move there to live, fish and hunt. It’s a fascinating place. The oldest human occupation dates back some 6,000 years ago. And we found a lot of evidence of plant cultivation, including rice, dating back some 4,000 years.

Mongabay: It was the U.S. archaeologist Betty Meggers who in 1954 launched the theory that the soil of the Amazon Rainforest is simply not fertile enough for agriculture and therefore could not support major populations and bring about a complex culture. Her theory dominated the archaeological conception of the Amazon for almost half a century. Today it seems there is hardly anything left of her intellectual legacy.

Eduardo Neves: Most of her insights are indeed no longer valid. A conservative estimate put the number of people living in the larger Amazon region prior to the European conquest at some 6 million to 9 million. The dominant view today is that they amounted to as many as 10 million people. And that has everything to do with agriculture.

We now know that the Amazon was one of the main cradles of plant cultivation in the world. There is no longer any doubt about that. Numerous very important plants were first cultivated in the Amazon, including manioc, cacao, papaya, peanuts and tobacco. It is a long list. And we now have the archaeological evidence to prove it. The Amazon was a center for agrobiological diversity.

But that is not all. What is the idea behind domestication? You take a wild plant and then select and manipulate its features in such a way that a new species comes into existence, which is dependent on human intervention for reproduction. In other words, genetic modification is essential for domestication and agriculture.

However, in the Amazon we also see many species that were never domesticated, such as the açaí tree, the Brazilian nut tree and the rubber tree. Not domesticated, yet very important, as they have been exploited as part of the rainforest for thousands of years.

The conceptual shift, which archaeology has helped achieve, is that the Indigenous people who used to live in the Amazon did practice agriculture, yet they did so in a different way. What an archaeological survey of the Amazon teaches us is that man and nature were fully intertwined and impossible to untangle. Which leads us to perhaps the most important paradigm shift of all: the Amazon Rainforest is not so much, or not only a natural heritage, but a biocultural heritage.

Mongabay: What does this revised understanding of the past tell us about the way we deal with the Amazon Rainforest today and in the future?

Eduardo Neves: The logic that has ruled the Amazon for thousands of years is the exact opposite of what is the dominant one today. The Indigenous worldview does not differentiate between the domain of culture and the domain of nature. The diversity of the Amazon, the presence of many large nut trees and fruit-bearing palm trees, is a result of Indigenous practices.

Modern man thinks from a division between nature and culture, and it is precisely this division that is destroying the Amazon. The idea that the Amazon must be conquered, colonized, transformed and domesticized — it simply does not work.

Look at what is happening today. We cut the forest, bring soy, corn, cows and grasslands. Over the last 50 years we’ve destroyed some 20% of the rainforest and, at best, some 50% of that is still somehow productive. Look at what happened in the Yanomami Indigenous Territory. Thousands of illegal gold miners were active there, destroying the landscape, poisoning the rivers with mercury. And who profits? A tiny group of people. It is a crime.

Mongabay: The ecomodernist movement, which has a growing popularity in the West, calls for an intensification of agriculture to create more space for nature and wildlife, with little or no room for people. Your opinion?

Eduardo Neves: Two things. First, the idea of a protected rainforest without people does not make sense. The past teaches us there were once many people spread out over a large territory. And there still are many traditional inhabitants, not only Indigenous people, but also ribeirinhos [riverside dwellers] and quilombolas [rural Afro-Brazilian communities]. And these are the people that help protect the rainforest.

Second, intensive agriculture is a concept that urgently needs reconsidering. The idea is to produce as much as possible of a certain crop in one area for as long as possible. But take the Brazilian nut tree that grows and flourishes as part of the forest for 300 or 400 years. That is incredibly intensive! In my opinion it is certain types of agroforestry that are incredibly intensive. And, not coincidentally, they return to techniques from the past.