HUMAN EVOLUTION × GENETICS

Out of Africa

~60,000 years ago

Phanerozoic · Cenozoic · Quaternary · Pleistocene · Late Pleistocene

Modern humans left Africa in one major expansion between 60,000 and 40,000 years ago, according to the genomes of 142 populations, and this expansion was not their first exit.

Out of Africa is the expansion by which modern humans spread from Africa to the rest of the world. The genomes of a hundred and forty-two populations, published by Mallick and colleagues (2016), point to one major expansion between sixty and forty thousand years ago. This interval overlaps the last established contacts with Neanderthals. The expansion was not the first exit. A maxilla, the bone of the upper jaw, was found at Misliya, in Israel. It attests a human presence nearly two hundred thousand years ago in the Levant, the eastern shore of the Mediterranean. This presence left no detectable descent in present-day populations. A population may therefore reach a region without persisting there, and only the later expansion left descendants.

Why it matters

Every population outside Africa descends for the most part from the single major expansion out of Africa. This common descent explains why human populations worldwide are genetically close. Further back in time, Bergström and colleagues (2021) find no single place of origin. The ancestors of these populations belonged to African populations that separated and reunited over hundreds of thousands of years, and their ancestry never converges on a single region.

Dating & uncertaintyDisputed

People reached the Levant between 194,000 and 177,000 years ago, and left no detectable descent. From genomes, researchers date the later expansion that peopled the world to about 60,000 years ago. The data therefore cannot be explained by a single date of departure.

Earth history as one day

23:59:581.1 s before midnight

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