Amazon research reveals centuries of human activity shape todays rainforest ecosystem

by Robert Schreiber
Berlin, Germany (SPX) Nov 19, 2025

A multinational team led by the University of Amsterdam has identified enduring effects of historical human activity on the Amazon rainforest. Using spatial modeling and an extensive collection of archaeological and biodiversity datasets, the researchers traced human settlement and resource use from pre-Columbian times through the colonial era, showing that patterns of forest composition reflect both Indigenous management and more recent European colonial extraction.

Study lead Crystal McMichael explained, "Our findings show that seemingly undisturbed parts of the Amazon forest have been shaped by people over hundreds or even thousands of years. These invisible legacies may still be affecting both ecosystem functioning and biodiversity."

Researchers analyzed over 7,000 archaeological sites alongside more than 100,000 digitized biodiversity records, comparing these with forest plot data for 262 Amazonian tree species. The investigation determined that Indigenous and colonial settlements clustered near major rivers, where forests continue to show increased abundance of species favored by people. Mark Bush, a co-author from the Florida Institute of Technology, observed, "Rivers have always been lifelines in the Amazon. They shaped how people moved, lived, and interacted with the forest - and that history is still being written into the ecosystem."

Many tree species with historic human uses, such as Brazil nut, rubber tree, and murumuru palm, are now widespread in regions marked by a long human presence. Study data further indicate that trees valuable for colonial-era construction and industry declined in areas of heavier exploitation, such as during the Amazon Rubber Boom.

Hans ter Steege of Naturalis Biodiversity Center noted, "Indigenous communities tended to actively manage forests and alter the balance of different species over time. Later colonial industries often extracted resources more intensively, leaving behind ecological scars that are still healing."

The authors conclude that much of the Amazon's biodiversity and carbon storage capacity reflects direct or indirect human influence rather than an untouched wilderness. They recommend that models for conservation and climate mitigation should consider both ancient and colonial legacies to make more accurate predictions about the future behavior of Amazonian forests.

McMichael added, "To protect the Amazon's future, we must first understand its past. Accounting for ancient and colonial legacies can help us better predict how forests will respond to deforestation, climate change, and reforestation efforts."

Research Report:Centuries of compounding human influence on Amazonian forests