HUMAN EVOLUTION

The Origin of Homo sapiens

~300,000 years ago

Phanerozoic · Cenozoic · Quaternary · Pleistocene · Chibanian

The oldest fossils attributed to Homo sapiens are a skull and a jaw found with stone tools at Jebel Irhoud, in Morocco, buried about 315,000 years ago, and the face of the skull is already like ours.

Homo sapiens is our own species, and the oldest fossils attributed to it come from Jebel Irhoud, in Morocco. They are a cranium and a mandible, that is, a skull and a lower jaw, found with a stone industry, a set of stone tools. They were buried about 315,000 years ago. Richter and colleagues (2017) dated them by thermoluminescence on heated flints found beside them. Thermoluminescence is a method that measures when a stone was last heated. The face is already like ours, but the braincase is still long and low. Jebel Irhoud lies at the north-western end of Africa, whereas earlier syntheses assumed that the species arose in East Africa.

Why it matters

On a timeline of 4.54 billion years, the history of Homo sapiens occupies the last 0.007 per cent. Researchers cannot name a place of origin for the species. Read together, the fossils and the genomes show no moment at which its ancestors were concentrated in a restricted region. The traits of the species came together across the whole of Africa, in populations that kept meeting and separating.

Dating & uncertainty

The Jebel Irhoud fossils are dated to 315,000 years ago, with an uncertainty of 34,000 years, from the heated flints found with the bones. The measurement is undisputed, but its interpretation is disputed. Jebel Irhoud is in Morocco and not in East Africa, and its occupants have only some of the modern traits. The model that has prevailed is called the pan-African origin. In this model, the species does not descend from a single population. Any date of origin, including 315,000 years ago, is then a conventional marker and does not record an event.

Earth history as one day

23:59:545.7 s before midnight

if Earth’s 4.54 billion years were compressed into a single day