An international team of researchers has uncovered the oldest evidence of human presence in the tropical forests of Africa. This groundbreaking discovery indicates that these 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,” reminded 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 Have Scientists Learned Now?
In a new study published in the journal Nature, the team of scientists 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 in the tropical forests even during dry periods when the forests existed only in fragments. We realized that this location is the best place to learn about how long humans have been living in tropical forests,” noted Professor Eleonora Sherri, head of the Human Paleoecology Research Group at the Max Planck Institute for Geoanthropology (Germany). Thus, the team set out for Côte d’Ivoire to re-examine the site.
“With the support of Professor Gede, we were able to rediscover this site and investigate it using technologies that were not available at that time,” said Dr. James Blinkhorn from the University of Liverpool (UK). Now, scientists have determined the age of the earliest human settlements in the tropical regions of Africa using cutting-edge dating methods, such as optically stimulated luminescence and electron spin resonance.
The researchers also separately analyzed sediment samples for pollen, plant remains known as phytoliths, and leaf wax isotopes. The results of the analysis convinced the team that during the time of the earliest human settlements, the region was densely covered with forests.
“This is an especially 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 research project was funded by the Max Planck Society and the non-profit organization Leakey Foundation based in San Francisco.