Gaby
An international team of researchers has uncovered the oldest evidence of human presence in the tropical forests of Africa. This discovery indicates that those regions were inhabited as far back as 150,000 years ago. Until now, scientists believed that the earliest human settlements in African forests were much more recent.
“Before our study, it was thought that humans settled in the tropical regions of Africa around 18,000 years ago,” said Dr. Eslam Ben Arous, a research fellow at the National Center for Human Evolution Research (CENIEH, Spain) and the lead author of the study. “The oldest evidence of habitation in tropical forests was previously found in Southeast Asia, dating back about 70,000 years,” he added.
The story of this new discovery began in the 1980s when Professor Yode Gede from the local Félix Houphouët-Boigny University first explored the tropical forests of modern-day Côte d’Ivoire as part of a joint Ivorian-Soviet research mission. At that time, researchers discovered a site in the tropical forest containing stone tools. However, they were unable to determine the exact age of the artifacts, as reported by Arkeonews.
What did the researchers find?
In a new study published in the journal Nature, the team found that humans lived in groups in the tropical forests of Côte d’Ivoire around 150,000 years ago—much earlier than previously thought.
“Several recent climate models suggest that this area served as a refuge during dry periods when the forests survived only in fragments. We realized this location would be the best place to learn how long humans have lived in tropical forests,” said Professor Eleonora Sherri, head of the Human Paleoecology Research Group at the Max Planck Institute for Geoanthropology (Germany). The team traveled to Côte d’Ivoire to re-examine the site.
“With Professor Gede’s support, we were able to rediscover the site and investigate it using technologies not available in the 1980s,” said Dr. James Blinkhorn from the University of Liverpool (UK). The researchers then determined the age of the earliest human settlements in these tropical regions using dating methods such as optically stimulated luminescence and electron spin resonance.
The team also analyzed sediment samples for pollen, plant remains called phytoliths, and leaf-wax isotopes. Those results convinced the researchers that the region was densely forested at the time of the earliest human settlements.
“This is an exciting discovery—the first in a long list of previously unexplored sites in Côte d’Ivoire that could provide additional evidence of human presence in tropical forests,” said Professor Gede.
The project was funded by the Max Planck Society and the Leakey Foundation, a San Francisco nonprofit.
