The understanding of human origins was turned on its head on Wednesday with the announcement of the discovery of fossils unearthed on a Moroccan hillside that are about 100,000 years older than any other known remains of our species, Homo sapiens.
Scientists determined that skulls, limb bones and teeth representing at least five individuals were about 300,000 years old, a blockbuster discovery in the field of anthropology.
The antiquity of the fossils was startling – a “big wow,” as one of the researchers called it. But their discovery in North Africa, not East or even sub-Saharan Africa, also defied expectations. And the skulls, with faces and teeth matching people today but with archaic and elongated braincases, showed our brain needed more time to evolve its current form.
“This material represents the very root of our species,” said paleoanthropologist Jean-Jacques Hublin of Germany’s Max Planck Institute for Evolutionary Anthropology, who helped lead the research published in the journal Nature.
Before the discovery at the site called Jebel Irhoud, located between Marrakech and Morocco’s Atlantic coast, the oldest Homo sapiens fossils were known from an Ethiopian site called Omo Kibish, dated to 195,000 years ago.
“The message we would like to convey is that our species is much older than we thought and that it did not emerge in an Adamic way in a small ‘Garden of Eden’ somewhere in East Africa. It is a pan-African process and more complex scenario than what has been envisioned so far,” Hublin said.
Fossil evidence points to an African origin of Homo sapiens from a group called either H. heidelbergensis or H. rhodesiensis. However, the exact place and time of emergence of H. sapiens remain obscure because the fossil record is scarce and the chronological age of many key specimens remains uncertain. In particular, it is unclear whether the present day ‘modern’ morphology rapidly emerged approximately 200 thousand years ago (ka) among earlier representatives of H. sapiens1 or evolved gradually over the last 400 thousand years2. Here we report newly discovered human fossils from Jebel Irhoud, Morocco, and interpret the affinities of the hominins from this site with other archaic and recent human groups. We identified a mosaic of features including facial, mandibular and dental morphology that aligns the Jebel Irhoud material with early or recent anatomically modern humans and more primitive neurocranial and endocranial morphology. In combination with an age of 315 ± 34 thousand years (as determined by thermoluminescence dating)3, this evidence makes Jebel Irhoud the oldest and richest African Middle Stone Age hominin site that documents early stages of the H. sapiens clade in which key features of modern morphology were established. Furthermore, it shows that the evolutionary processes behind the emergence of H. sapiens involved the whole African continent.