Environment featured

A short walk through Amazon time: Interview with archaeologist Anna Roosevelt

April 12, 2024

  • Anna Roosevelt has been working in the Amazon for four decades and her pivotal research has changed the knowledge of the rainforest’s occupation.
  • In an interview with Mongabay, she explains how her research led to evidence of much older Amazon settlements than previously thought, challenging a decades-long scientific consensus about how Indigenous people related to the forest.
  • “One reason I was able to make some great discoveries is because of how opinionated archaeologists in the mid-20th century were. I only benefited from their mistakes,” she said.
  • Roosevelt said the recent hype regarding the “garden cities” in Ecuador is “annoying”, as it is not a new discovery and it ignores older research from Latin American archaeologists.

A professor of anthropology at the University of Illinois Chicago, Anna Roosevelt has been dubbed the “matriarch” of archaeology in the Amazon River Basin. In a career spanning some 40 years, she has authored more than a hundred scientific articles and a dozen books, which helped accomplish a radical shift in the way we perceive the past of the human presence in the Amazon.

Known as environmental determinism, the dominant view for decades was that the tropical rainforest was too hostile, too wet, too infertile to bring forth any complex culture. Additionally, the human presence in the Amazon was thought to be a relatively recent phenomenon, consisting mainly of small bands of hunters and gatherers and simple gardeners.

Having worked from the Orinoco floodplains to the Monte Alegre caves and from Marajó Island to the tropical forests of the Congo River Basin, Roosevelt smashed the pillars upon which the “false faith” was built. Today, thanks to archaeologists like her, almost everything regarding the human past of the Amazon is the exact opposite of what was taught in academia only 50 years ago.

Erudite and witty, Roosevelt is the first to acknowledge that she did not do it alone. Too many before her remained ignored for far too long.

“From an ecological point of view, the significance of the [archaeological] sequence is that the Amazonians have always very much managed the rainforest and rivers,” she said. “They didn’t deforest, but further developed and enriched the natural diversity.”

Despite the many existential threats facing humankind and the world, Roosevelt is remarkably positive about what the future can bring.

“Let the forest come back. Just let it grow, and it will come back by itself. The forest produces more food per hectare than traditional agriculture or a savanna pasture, and it generates water, which will help tackle future droughts.”

Anna Roosevelt looking at imagery at the Painted Rock Cave near Monte Alegre dating back to 11,000 BCE. Image courtesy of Anna Roosevelt.

Anna Roosevelt spoke with Mongabay by video on Dec. 1, 2023, and Jan. 15, 2024. The conversation was edited for clarity and brevity.

Mongabay: How did you first develop an interest in archaeology? 

Anna Roosevelt: Through my mother. She loved archaeology. Her parents were from Missouri but had moved to the U.S. Southwest because they had tuberculosis. At the time, there was no way to treat the disease. If possible, people would just move to a drier climate. So, my mother grew up in Arizona and New Mexico, where she often went around with this doctor who liked archaeology. Later, she took me and my sisters to parks, museums and archaeological sites like Mesa Verde, Colorado. And I found it all so exciting that one day I said, ‘I want to be an archaeologist.’ I think I was 9. And my mother thought that was OK.

Mongabay: Your late great-grandfather, former U.S. President Teddy Roosevelt, explored the western Amazon in 1913. Did that influence you at all in becoming an archaeologist in the Amazon?

Anna Roosevelt: No. I didn’t really know much about him when I grew up. Except that he was overweight. And that my grandmother didn’t like the way he slurped his soup. It was too noisy [laughs]. Seriously, he died in 1919, almost 30 years before I was born, so he wasn’t a presence. Only later, as a student, I learned more about him.

Mongabay: Most aspiring archaeologists dream of working in ancient Rome, Greece, or Egypt. How did you end up in the Amazon Rainforest?

Anna Roosevelt: At first, I was interested in the classics too. But two things happened that took me to South America instead of the Mediterranean and Near East. As a college student, I worked as an intern at the Natural History Museum in New York. My supervisors were archaeologists and they treated me and the other interns so wonderfully well. They made it all so interesting. Then I read one of their books on Peru, and I saw the mummies, the caves and desert sites. That is what first drew me to South America.

Then, archaeology at the time held there were two nuclear areas in South America: the Andes and Mesoamerica. That’s where all development happened, supposedly. But I wasn’t convinced. So, for my dissertation, I decided to focus on the intermediate area, the floodplains of the Orinoco River. The hydromorphic soil of the Orinoco was the same as the Nile’s, so I asked myself: Why would plant cultivation have been a problem for the ancient people in this part of the world if it wasn’t for the ancient Egyptians?

Roosevelt’s team at work In a boat at Curupité, Amazon, in 2000. Image courtesy of Anna Roosevelt.

Mongabay: That is where you, among other things, touched upon a rich agricultural practice.

Anna Roosevelt: At the time, many people said you could not study plant remains, as the wet conditions of the tropical forest could not preserve them. But I knew that could not be true. Carbonized plant remains are almost indestructible.

At the Orinoco, I was looking at ceramic cultures dating from about 1,000 B.C.E. to 1,500 C.E., when people lived in permanent settlements and depended on agriculture. What I found was that the earliest people living on the flood plains didn’t have corn yet, but probably had manioc, a tropical lowland crop. The next ones had a little bit, while the late ‘prehistoric’ peoples, between 850 and 1500 C.E., had buckets of it.

However, this was a different kind of corn. The first maize is known as pollo. This is a highland maize, which makes sense as it was coming from the Andes or Mesoamerica. The abundant kind was a different one, known as chandelle, named for its candle-like shape.

This is a tropical maize. So, probably the local people selected from the highland variety to adapt it to the lowland environment and eventually got a type that thrived and became a staple food. How do I know that? Because the bones of the human skeletons I studied were full of corn carbon.

Mongabay: So, your first steps as an Amazonian archaeologist you took along the Orinoco?

Anna Roosevelt: That is where I did my first little chunk of the sequence of the Amazon. And that worked out OK. I mean, I did my dissertation, which was published by Academic Press.

As I was working as a curator at the time, I thought my next step should be to have a look at all the collections of all the museums I could get to, to see what was there. That’s where I saw my first projectile points, which would eventually lead me to Monte Alegre.

Anna Roosevelt giving a Fulbright class at Curupité in the Xingu region in 2002. Image courtesy of Anna Roosevelt.

Turning back the clock

Situated on the northern bank of the Amazon River in the Brazilian state of Pará, Monte Alegre is famous for its prehistoric rock paintings depicting animals, human figures and geometrical symbols. In the early 1990s, Roosevelt carbon-dated samples from the Painted Rock Cave and her results stunned the scientific world. Humans had been living at Monte Alegre since as early as 11,000 B.C.E, while the academic consensus at the time was that the human presence in the Amazon did not exceed some 2,000 years.

Mongabay: Can you tell us a bit more about how you first got to Monte Alegre and the site’s importance?  

Anna Roosevelt: I first went there on a weekend while digging at Taperinha, a few hours south of Santarém. Monte Alegre cave is wonderful. Sunny during the day. Warm at night. Not far from the huge lakes that have shellfish and fish, and a forest full of fruits and other edibles.

I went there and asked if anyone knew about the rock art. Fifteen minutes later, someone appeared and led me to Monte Alegre sites, including the Painted Rock Cave and its painted wall designs. From the stratigraphy, I immediately realized the cave was not too disturbed inside. The deposit below the entrance held lots of lithic fragments, but there was pottery at the top, so I thought I could get a sequence. I applied to the National Endowment for Humanities and got a grant to dig there.

We ran 67 radiocarbon dates. That’s a lot. Archeologists will often do only two or three. I will never forget the moment I got the results from the lab. I was in a hotel in Belém when I got the email. It was the middle of the night. I was alone, so I had no one to talk to. But I still remember my dream that night. It was a view of the entire sequence of the Amazon. I always thought that dream would make a great movie.

Anyway, of course, I was delighted and positively surprised. But I had always found it strange that people thought the Amazon had been occupied by humans for only a few thousand years. It just didn’t make sense to me. As a curator, I had seen the flaked projectile points as well as some very early pottery. And then there were 19th-century scholars, like Alfred Russell Wallace, who had said that the human presence was much older, based on Monte Alegre.

You should know that the mid-20th-century archaeologists, who set forth the theory that the rainforest was too harsh and infertile an environment to support a complex culture, completely ignored the work of the previous generation of scientists. Everything I ‘discovered’ the 19th-century naturalists already knew about.

A large-stemmed point and palm-wood harpoon foreshaft found by miners at Curupité in 1986. Image courtesy of Anna Roosevelt.

Mongabay: Taperinha is famous for its shell mounds, which are essentially ancient garbage dumps with, among other waste, piles of mollusk remains. At the bottom you found some of the oldest pottery in South America dating back to the 8th millennium B.C.E., which is yet another indication that the human presence in the Amazon dates back much further than previously thought. Can you tell us a bit more about the site where, as was the case in Monte Alegre, previous knowledge seemed to have been long ignored?

Anna Roosevelt: Taperinha is a wonderful site, located about four hours by boat from Santarém. Before going there, I had read the work of, among others, Charles Hartt, a Canadian geologist who worked at Taperinha in the 1870s at the suggestion of Domingos Soares Ferreira Penna, then director of the Goeldi Museum, in Belém. According to him, the site belonged to a community of fishing people in the early Holocene [the current geological epoch, which started around 9,700 B.C.E.].

Hart had collected some shellfish and pottery, which were part of the collection in the . I had them carbon-dated and it turned out they were some 6,000 years old. All I did next in Taperinha was dig to the bottom of the some 6-meter- [20-foot-] high shell mounts, where I found even older ceramics, which confirmed Hartt’s opinion and showed that tropical forests were by no means too poor or infertile to allow for preagricultural settlement.

So, in a way it was not a big discovery. It only became one because  leading 20th-century archaeologists had decided that the mounds had to be of a more recent date. Why? I don’t know. Because it did not fit the dominant theory of environmental determinism, I suppose. Really, one reason I was able to make some great discoveries is because of how opinionated archaeologists in the mid-20th century were. I only benefited from their mistakes.

Mongabay: When archaeologists talk about pottery or ceramics, often the term “The Formative Stage” pops up. Could you briefly explain what it means? And how does it relate to the Amazon?

Anna Roosevelt: What archaeologists call ‘the Formative’ — not the most appealing term, I admit — refers to the later stages in the cultural evolution of the New World, roughly dating from 2,000 B.C.E. to 500 C.E. It was the era when people generally settled down and farmed. Some of the most recognizable Formative pottery [in the Amazon] is a kind of reddish pottery with smooth surfaces, sand tempering and rather nice grooving and modeling. I first encountered it during my research in the flood plains of the Orinico and on every dig I worked on since. In Taperinha. In Monte Alegre. In Marajó.

Anna Roosevelt with archaeologists and local miers at Curupité in 2000. Image courtesy of Anna Roosevelt.

The Marajó culture

Prior to the European conquest, Marajó Island in the mouth of the Amazon River was home to a large population, possibly amounting up to 100,000 people. They lived on earthen mounds, cultivated and collected plants, and produced some of the most dramatic ceramics on the continent. Formulated in the 1950s, the dominant theory for decades was that the Marajó culture, including its pottery, stemmed from the Andes. In line with the limitations of environmental determinism, it was assumed that the Marajó culture had been short-lived, while the mounds were thought to be only ceremonial.

Mongabay: You worked at Marajó Island for many years. How did you first get there? And what would you say were your most important findings?

Anna Roosevelt: As I was going around looking at museum collections at the time, I met the then-director of the Emilio Goeldi Museum in Belém, José Seixas Lourenço, a geoscientist who had found evidence of domestic occupation at the Marajó mounds, while the dominant view was that they were just ceremonial.

He invited me to work with him. We got a grant to dig from the National Science Foundation and found that the mounds we excavated represented long-term human occupations from soon after the start of the common era until at least 1,100 or 1,200 C.E.

Some of the mounds at Marajó are clustered closely together in large groups, and it seems that there were some 25-30 families per mound village with cultivated açaí palms all around. Like garden cities. We found the foundations of many large houses, the typical Amazonian communal homes. In the middle, they had 6-12 stoves with room for three pots each. Usually, in Amazonia, when wives are brought in from outside, they keep a separate stove, while when women are related, say sisters, they cook together.

What we also found is that the eastern Amazonian polychrome [multicolored] ceramic cultures were a lot older than the related Andean foothills cultures of the upper Amazon. In other words, the latter could not have been the source of the first.

Instead of people and polychrome pottery coming from the Andes, I think Marajó was the origin. The particular ceramic style traveled westward along the Amazon drainage all the way to Peru, Ecuador and Colombia. Each culture had its own interpretation, but the main pattern representing the anaconda skin patterns remained.  It represents the main deity, the woman shaman, whose spirit animal is the anaconda.

In 2010, Eduardo Neves organized a meeting in Manaus, for which he also invited people from the Rio Negro region and people from other polychrome cultures across the Amazon. So, I showed them the images in my book on Marajó and all of them said, “That’s the anaconda.”

Mongabay: You also worked in Santarém, where it seems there was an even more elaborate urban culture than in Marajó, although we may never know the exact details.

Anna Roosevelt: In Santarém, we mapped some 4 square kilometers [1.5 square miles] of dark soil [terra preta]. That is huge for a prehistoric site. The mounds were smaller than in Marajó, like for single-family houses. But there were big earthen platforms for ceremonial rituals. We don’t know much about the houses, but each one had a deep pit with cremated human bones and feasting remains next to it. The Santarém culture was more urbanized and more populated, with a more intensive flood plain agriculture than Marajó.

The pottery is from another, later style known as the Incise and Punctuated Horizon — sorry, another horrible term. It is the same style to which the corn-eating people of the Orinoco belong. We believe there was a huge settlement in Santarém, but it will be hard to further study the site, as it was bulldozered to make way for the Cargill soybean shipping terminal.

Roosevelt with her team at a Kayapó village in the Xingu in 2002. Image courtesy of Anna Roosevelt.

Mongabay: On Jan. 11, Science published the study Two thousand years of garden urbanism in the Upper Amazon, which claims “a dense system of pre-Hispanic urban centers has been found in the Upano Valley of Amazonian Ecuador.” The lidar remote sensing technology revealed, among other things, clusters of platforms and plazas, interconnected by roads, as well as extensive agricultural terraces and drainages. Your thoughts?

Anna Roosevelt: Well, it’s great that Stéphen Rostain [one of the archaeologists in charge in Ecuador] and his colleagues went back and firmed up and expanded the evidence. But the hype annoys me, as it is not a new discovery at all.

In 1987, Father Pedro Porras published a monograph that makes clear the urban garden character of the site, with photos very much like the drawing in the Science article, as well as pictures of the agricultural terraces. The site is more than 10 km2 [3.9 mi2] and is Formative in age. Both these facts are mentioned in Porros’ monograph. He included stratigraphic profiles, illustrations of the artifacts and numerous radiocarbon dates of Formative age.

So, there is nothing new in the Science article except a confirmation of Porras’ research findings and a refinement of the site map. It bothers me that the Science authors tend to misrepresent their own findings and not acknowledge the original findings by a South American author.

Mongabay: What does Amazonian archaeology have to do with Africa?

Anna Roosevelt: Well, if you take Monte Alegre as an example, it shows us that people living there were broad-spectrum foragers rather than big game hunters. Also, Amazonia presents an example of a tropical forest basin in which Native people developed a long sequence of very diverse cultures. This is relevant for the interpretation of human history in, for example, the Congo rainforest.

In Africa, just as in South America, consensus theorists made very wrong assumptions about the history of the habitat, its human occupation, and human evolution. The long-dominant theory was that our ancestors evolved by leaving the forests for the savanna.

This assumption now seems almost entirely wrong. Still, further research is needed, but the picture emerging from preliminary research in sub-Saharan Africa suggests a very different history, which could have implications more important even than Amazonia’s. Our image of the past and present in Africa is dominated by the savanna created during globalization after 1,500 C.E. But it is adaptation to the forest that should take center stage in prehistory.

Anna Roosevelt with her team in Ngolio in the Central African Republic. Image courtesy of Anna Roosevelt.

Mongabay: What is the importance of the changed archaeological and historical perspective on the Amazon for modern-day ecology?

Anna Roosevelt: From an ecological point of view, the significance of the [archaeological] sequence is that the Amazonians have always very much managed the rainforest and rivers. They did slash-and-burn, but on a limited scale and built raised agricultural fields on the flood plains, as Stéphen Rostain has shown. They didn’t deforest widely but further developed and enriched the forest’s natural diversity. The forest is the main source of rain and nutrients in the tropics.

One thing scientists have discovered is that the main source of rain in tropical rainforests is not evaporation from the oceans but from the rainforest itself. The moisture is held within the body of the forest. Moisture transpires from the trees and then falls as rain both there and elsewhere. So, the forest produces much more moisture than it needs.

In Africa, the Congo rainforest has been much reduced yet still provides a lot of the rain as far away as Ethiopia, Chad and Niger. Global drought may not be such a problem if you restore and preserve the forests.

The forest per hectare is a much more productive source of valuable materials than, say, a field of soybeans or cattle pasture. And most of the many useful and common plants are not yet on the market, except locally. Take moriche [a palm, Mauritia flexuosa]. Today, almost everyone in the West consumes drinks made of açaí berries, but that is just one of the many valuable fruits in the Amazon, and not even the most productive one. It’s a relatively small fruit and does not have much pulp.

There are thousands of moriche palm trees in the flood plains. It’s a much larger and fleshier fruit and makes a wonderful jam, but it is only eaten locally. There are many ways Amazonians can support themselves and their countries’ trade balance, while improving the continental climate at the same time.

Peter Speetjens

Peter Speetjens is a Dutch journalist. Following his law studies in Rotterdam, he spent some 20 years in the Middle East and India, before moving to Brazil in 2016. Based in São Paolo he mainly writes about politics and the environment. His work has appeared in numerous Dutch and English language publications, including MO Magazine, Middle East Eye, Trouw, NRC and De Groene Amsterdammer. He has a soft spot for history, loves photography and in 2004 coauthored the documentary 2000 Terrorists.