For generations, scientists looked to the East African savanna as the birthplace of our species. But recently some researchers have put forward a different history: Homo sapiens evolved across the entire continent over the past several hundred thousand years.
If this Africa-wide theory were true, then early humans must have figured out how to live in many environments beyond grasslands. A study published Wednesday shows that as early as 150,000 years ago, some of them lived deep in a West African rainforest.
“What we’re seeing is that, from a very early stage, ecological diversification is at the heart of our species,” said Eleanor Scerri, an evolutionary archaeologist at the Max Planck Institute of Geoanthropology in Jena, Germany, and an author of the study.
In the 20th century, after scientists found many fossils and stone tools in East African savannas, many researchers concluded that our species was especially adapted to life in grasslands and open woodlands, where humans could hunt great herds of mammals.
Only much later, the theory went, did our species become versatile enough to survive in tougher environments. Tropical rainforests appeared to be the toughest of them all. It can be hard to find enough food in jungles, and they offer lots of places for predators to lurk.
“You can’t see what to hunt,” Dr. Scerri said, “and you can’t see what’s coming for you.”
But in 2018, Dr. Scerri and her colleagues challenged the idea that East African grasslands were the single cradle of humanity. The abundance of stone tools and fossils found there, they argued, might have meant simply that the region had the right conditions for preserving those traces of history.
