Jebel Irhoud in brief
Jebel Irhoud is a hill about 100 kilometres west of Marrakech, in Morocco, where a mine once dug barite, a mineral used in industry. The cave deposits in the old mine hold human fossils, stone tools, burnt flint and animal bones. In 2017 a team reported that these were about 315,000 years old (with a range from about 280,000 to 350,000), around 100,000 years older than the next oldest Homo sapiens fossils then known.
Discovery
In 1961 miners blasting at the site broke open a skull, and the find was reported to scientists. Over the next years a second skull and a child’s jawbone were found. At first, they were considered to be African Neanderthals, since they look primitive in some ways, and later to be early modern humans. For decades their date was uncertain, at around 160,000 years.
In 2004 Jean-Jacques Hublin of the Max Planck Institute for Evolutionary Anthropology in Leipzig, with Abdelouahed Ben-Ncer of the Moroccan National Institute of Archaeology and Heritage, began new excavations. They found more fossils, from at least five individuals, together with stone tools that include sharpened flakes and points made on prepared cores. Burnt flints in the same layers made it possible to date them by heating (thermoluminescence), and a tooth was dated by a second method. Both gave the new age, reported in Nature in 2017.
What the fossils show
- Face. Modern: small, short and flat, tucked under the front of the brain case, with a form and teeth like ours.
- Braincase. Long and low, unlike the high round head of people today. Its size, about 1,300 to 1,400 cubic centimetres, is within the modern range, but its shape suggests that the brain was organised differently.
- Stone tools. Middle Stone Age, with flakes and points of types that were also used by later sapiens and by Neanderthals.
- Fire and food. Hearths and burnt flint, and the bones of gazelles, which seem to have been the main prey.
Why it matters
Before Jebel Irhoud the oldest accepted Homo sapiens fossils were from Ethiopia, around 200,000 years old. Jebel Irhoud pushed our species back to about 300,000 years ago, and put it in North Africa, far from East Africa. In the researchers’ view it shows that our species did not evolve in one small place, but across the whole of Africa, in populations that were linked by gene flow and trade. It also fits with other African fossils of about the same age, such as Florisbad in South Africa and Omo Kibish in Ethiopia. See Homo sapiens.
Not everyone calls these fossils Homo sapiens in the strict sense. Some prefer to see them as an early form of a lineage that led to us, with the fully modern skull shape developing later. That disagreement is partly about words, since we know the people of Jebel Irhoud looked partly modern.
Visiting
The mine is a research site and is not set up for visitors. The fossils are kept in Morocco, and they are studied by Moroccan and international scientists.
Sources
- Hublin, J.-J. and others (2017). New fossils from Jebel Irhoud, Morocco, and the pan-African origin of Homo sapiens. Nature 546: 289 to 292.
- Richter, D. and others (2017). The age of the hominin fossils from Jebel Irhoud, Morocco, and the origins of the Middle Stone Age. Nature 546: 293 to 296.