Our species, Homo sapiens, are thought to have emerged from ancient hominins around 300,000 years ago. Hominins were previously thought to have lived and evolved in East Africa – migrating to the Northern part of the continent around a million years later. This was supported by artifacts found in the late 1990s in a site called Ain Hanech in Algeria – dating back 1.8 million years. In comparison, the oldest tools in the world were uncovered in East Africa – dating back 2.6 million years. Now, new evidence has provided support to the theory that early hominins existed throughout Africa at the same time, and not just in the East.
Back in 2006, an archaeologist at Spain’s National Research Center for Human Evolution by the name of Mohamed Sahnouni investigated some interesting artifacts at a site called Ain Boucherit in northeastern Algeria near the city of El-Eulma. These items were embedded in a sedimentary layer exposed by a deep ravine. After discovering another layer at the same site to years later, Sahnouni and his team meticulously worked to uncover a trove of stone tools and butchered animal remains at the site – which included mastodons, elephants, horses, rhinos, hippos, wild antelopes, pigs, hyenas, and crocodiles. Clearly, the early hominins weren’t picky eaters.
They used three different dating techniques to estimate the age of the remains. Using magneto-stratigraphy, Electron Spin Resonance (ESR) dating, and a bio-chronological analysis of the animal bones – they were able to find the exact age of the two stratigraphic layers, dubbed AB-Up and AB-Lw. While AB-Up was found to be 1.9 million years old, AB-Lw was even older at 2.4 million. Thus they were older than the previously found objects in Ain Hanech, while being slightly younger than the oldest artifacts ever to be discovered.
The details of the study were published in Science, suggesting North Africa wasn’t just a place where human ancestors lived and developed tools—it was a place where they evolved. Sahnouni, the lead author of the study, also suggests that the findings show evidence of a much earlier dispersal date into the continent. He said, “The evidence from Algeria has changed our earlier view regarding East Africa as being the cradle of humankind. Actually, entire Africa was the cradle of humankind.”
The method that the researchers used had been both praised and criticized. Eleanor Scerri, an archaeologist from the University of Oxford, said the researchers did a great job with the dating, saying it’s “incredibly difficult” to accurately date ancient hominin sites. Meanwhile, Jean-Jacques Hublin – a researcher from the Max Planck Institute for Evolutionary Anthropology – wasn’t thrilled with the dating techniques employed. He said, “Paleomagnetism is not a dating method. It helps to constrain dates obtained by other methods and is subject to various interpretations.”
Nonetheless, the research highlights the importance of North Africa, and also the Sahara, for archaeologists seeking to learn more about human origins. Scerri said, “Exploring the Sahara and other areas that are in the less glitzy corners of the human origins map will likely yield important returns, which in no way diminishes the incredibly important and valuable finds from eastern and southern Africa.”