“Science is not linear.”
This phrase was said by one of the most brilliant and humane scientists I had the pleasure of meeting: . And, in fact, it is not linear, neither in its production process, nor in relation to those who produce it.
Who produces science? One of its main objectives is to improve people’s lives, whether through understanding the world or through technological advancement. But it is rarely discussed how science profoundly transforms the lives of those who produce it.
“I, Allan Sandes, resident of a community in Rio de Janeiro, had my destiny transformed with access to higher education. Access was through public policies aimed at the inclusion of socially vulnerable students in the public university. At this moment, the non-linearity of science blends into my own history.”
After completing my undergraduate degree in geography and my master’s degree in marine geology, I began my doctorate in ocean and earth dynamics, under the guidance of the professor. At that moment, I still had no idea how my life would be transformed.
Cleverson Guizan, one of the most respected marine geologists in Brazil, made the invitation that would change the course of my professional and, above all, personal trajectory.
Through a partnership between UFF () and , financed by the program, which fully funded the training of Brazilian students at foreign universities, I was invited to develop part of my doctorate in the United States, under the supervision of then professor Paul Baker.
“I’m from Niterói, resident of , a community in the city.”
Paul, surprised, asked:
“Are you from the favela?”
Upon my affirmative response, he interrupted the conversation and said something I have never forgotten:
“Do you have any idea what’s going on in your life? You, a resident of a favela in Rio de Janeiro, are at one of the best universities in the world. Do you have any idea how great this feat is?”
At this point, I return to the question I presented at the beginning of this article and add: who produces and who can do science?
For a long time, I saw my academic trajectory as the result of an unlikely succession of opportunities. But no. The apparent linearity regarding who can occupy the spaces of science can be broken by public access and permanence policies aimed at historically marginalized groups.
How many scientific talents remain invisible simply because they never had the opportunity to access these spaces? Interestingly, the very science that we began to produce also began to break consolidated paradigms.
NEW STORIES FOR THE AMAZON
The core was recovered during an expedition by the oceanographic vessel R/V Knorr (KNR197-4), carried out in February 2010, on the Brazilian continental margin, in the Pará-Maranhão Basin, south of the Amazon Cone.
The project, led by Paul Baker and Cleverson Guizan, aimed to understand the climatic and biogeographic evolution of tropical South America throughout the Quaternary.
What made the CDH-79 special was not just its location, on a seamount located 2,345 meters deep; but, mainly, its temporal extension potentially preserved in the sediments.
During the development of the preliminary age model, the first surprise emerged: the results indicated an age close to 2 million years. The discovery seemed unlikely. Other testimonies collected on the same expedition were much more recent in age.
We reran the analyzes and the results remained consistent. With the arrival of complementary analyses, including radiocarbon and oxygen isotopes, it became evident that we were facing one of the longest paleoclimatic records ever obtained for the Amazon region.
More than a sedimentary core, CDH-79 represented an unprecedented window into understanding the climatic history of tropical South America over the last 2 million years.
Over the following years, we delved into one of the Amazon’s most challenging questions: after all, was the Amazon drier or wetter during glacial periods?
For decades, the idea prevailed that glacial periods would have been marked by a drier and more fragmented Amazon. However, records obtained from CDH-79 began to reveal a more complex story.
The, from indicate that Amazonian hydroclimatic variability over the last 2 million years was much more dynamic than previously imagined.
At different times, glacial periods were associated with an increase in Amazonian sediment discharge and the intensification of extremely humid events, strongly connected to climate changes occurring in the North Atlantic.
More than reconstructing the Amazon’s climatic past, the study revealed the deep connection between different regions of the planet. Changes in the North Atlantic ocean circulation were capable of reorganizing tropical atmospheric systems and profoundly altering the hydrological regimes of South America.
TWO STORIES, THE SAME RUPTURE
In many moments, I felt that the work I was doing reflected what Paul Baker had told me years before: science is not linear. Nor in its results and interpretations. Not even in the human trajectories that build it.
The CDH-79 testimony revealed an Amazon that was more dynamic and complex than we imagined. My own trajectory has revealed that scientific talent can also emerge from places that are often excluded from the spaces of knowledge production.
Years after that conversation at Duke University, I returned to the same public university where I had started my academic career, this time as a professor and researcher, I received the Oscar for Brazilian Science, the , and . Maybe that’s why the question about who can do science continues to haunt me.
Because, in the end, science is also about belonging. About showing that young people from peripheral areas and favela residents do not need to appear only as an object of social or environmental statistics. They can also produce cutting-edge knowledge, lead scientific expeditions, publish in high-impact international journals, and help rewrite what we know about the planet’s climate history.
Perhaps the main lesson of recent years is that knowledge advances precisely when we question what seemed obvious, whether about the functioning of the Earth’s climate system or about who can participate in the construction of this knowledge.
Science is not linear. And perhaps that’s exactly why she continues to be able to surprise us.
This text was originally published by The Conversation Agency, on June 18, 2026. The content is free for republication, citing the source, and was adapted to the standard of Poder360.
