A quarter of a million years ago, the East African Rift zone was a fertile causeway, where ample rainfall collected in basins among the hills, and fertile soils were laced with ash from a series of active volcanoes. This region is also thought to be the birthplace of our species, Homo sapiens, based on a rich nexus of archaeological sites.
Now, scientists have dated a famous set of remains from the rift zone in Ethiopia, known as Omo I, firmly identifying them as the oldest modern human remains in eastern Africa, and the oldest unquestioned evidence of H. sapiens in the world.
“It’s probably no coincidence that our earliest ancestors lived in such a geologically active rift valley – it collected rainfall in lakes, providing fresh water and attracting animals, and served as a natural migration corridor stretching thousands of kilometres,” says Clive Oppenheimer, a volcanologist at Cambridge University, UK, who is attempting to date volcanic eruptions from the region at the time of our species’ origins.
“The volcanoes provided fantastic materials to make stone tools and from time to time we had to develop our cognitive skills when large eruptions transformed the landscape.”