Biologist Cintia Freitas analyzes plant genetics in conjunction with archaeological data to reveal how Indigenous peoples have influenced the landscape

Art by Lívia Serri Francoio

By Murilo Bomfim

When Gonçalves Dias wrote the opening verses of “The Song of Exile,” he probably had no idea which specific palm tree he was referring to. In fact, palm taxonomy is a complex field, even for experts. Until recently, genetic analysis allowed scientists to identify palm families (groups of related genera) and genera (groups of related species), but not individual species.

Palm species are more easily distinguished by their appearance (phenotype) than by their genetic code (genotype), which shows only minor variations. Recent advances in molecular techniques, however, have allowed researchers to classify some families and genera into distinct species.

Gonçalves Dias, a native of Caxias, Maranhão, couldn’t have known why the palms he wrote about were so abundant in his homeland. Palms can be found throughout Brazil, with iconic species in each region: the açaí in the north, the butiá in the south, the coconut palm along the coast, and so on. Unraveling the story of how these species came to inhabit their current regions is one of Catia Freitas’s main research interests.

Like the palms she studies, Freitas has a broad geographic range throughout Brazil. A native of Pernambuco, she graduated from the Federal University of Pernambuco, earned her Ph.D. from the National Institute of Amazonian Research in Manaus, and completed a postdoctoral fellowship in Goiás. She also served as a professor at the Federal University of Pampa in Santa Maria and is currently a researcher at the Federal University of Rio de Janeiro. Her journey across the country was no accident; she intentionally developed projects that allowed her to explore as many biomes as possible. With the exception of the poles, Freitas has firsthand knowledge of nearly every biome in the Americas.

In each biome, Freitas has taken the time to observe the landscapes and reflect on the historical influences that have shaped them into what they are today. One of her main goals is to emphasize a point she feels is often overlooked by ecologists: humans have played—and continue to play—a significant role in shaping the distribution of plant species across the environment.

“Ecology is a hard science that uses mathematical models to make predictions,” she explains. “But human actions are often overlooked in those models.” She admits she once held this view, when she moved from studying the Atlantic rainforest to the Amazon to explore a biome untouched by human influence. “But which humans are we talking about?” she asks today.

Freitas hypothesizes that the Indigenous peoples inhabiting Brazil since well before 1500 actively cultivated plants near their settlements. Through land management, which provided essential resources such as food, building materials, and tools, these communities inadvertently reshaped the landscape over time. 

While simple in concept, proving this theory is complex. To build her case, Freitas is studying the distribution of butiá palms in Rio Grande do Sul. Using advanced molecular techniques, she has mapped the genome of the species and cross-referenced this data with archaeological records of Indigenous settlements and migration routes, linking genetic changes to timelines of human activity. This approach allows her to trace the evolution of both species and landscapes simultaneously.

The results could challenge a dominant paradigm in ecology, redefining humans as integral components of nature rather than passive observers. One of the most significant implications of this shift may be the development of new conservation strategies, as current management models often overlook the role of human intervention in shaping ecosystems.

“Many regional conservation laws ignore the relationship between nature and local communities—it’s the myth of pristine nature,” she explains. “We need a vision that is more rooted in our ancestral connections and recognizes that Indigenous knowledge has profoundly impacted the abundance, distribution and genetic diversity of useful species.”

Like the palm trees in the poetry of Gonçalves Dias, many landscapes often considered “natural” are likely the result of thousands of years of human interaction with the environment.

This text was originally publicated on Serrapilheira’s Ciência Fundamental blog on Folha de S.Paulo