History › Human origins › Homo sapiens: modern humans
Out of Africa migration
main dispersal c. 70,000–50,000 years ago· Event· Middle East & Africa
Mostly agreedGood evidence; some details, dates or numbers uncertain.
Between about 70,000 and 50,000 years ago, modern humans left Africa in numbers and spread across Asia, Europe and beyond.
See it on the History map →What happened
Small groups had ventured into the Middle East earlier, by about 190,000 years ago, but those early lines largely died out. The main dispersal, ancestral to all non-Africans today, left either through Sinai into the Levant or across the narrow southern Red Sea strait into Arabia. Along the way migrants interbred with Neanderthals, and in Asia with Denisovans. By about 45,000 years ago their descendants lived from Europe to Australia.
Why it matters
It explains why people everywhere outside Africa are closely related, and why Africa still holds most of humanity's genetic variety.
How we know
Mainly DNA from living people and ancient bones, which traces family trees and dates the Neanderthal mixing to roughly 50,000–45,000 years ago, plus dated fossils and stone tools along the routes.
Still debated
The exact routes, the timing, how many waves there were, and whether climate shifts pushed or pulled people out are all still argued.
Inside this (2)
Connections (4)
▸Homo sapiens: modern humans spread worldwide in the Out of Africa migrationMostly agreed
The connection
After some 200,000 years living mostly in Africa, Homo sapiens populations grew, developed more flexible technology and moved out. A main wave about 70,000–50,000 years ago produced the ancestors of everyone outside Africa today.
When and how
Northeast Africa into Arabia and the Levant, about 70,000–50,000 years ago; earlier forays reached Israel by about 190,000 years ago.
How sure are we?
DNA from living people worldwide traces non-African lineages to a small group that left Africa; fossils such as Misliya Cave in Israel date earlier forays.
Debates and open questions
What triggered the exit, wet periods that greened Arabia, new technology or population growth, is debated.
▸Out of Africa migration met and interbred with NeanderthalsWell documented
The connection
As modern humans moved through the Middle East and into Europe and Asia, they met Neanderthals and had children with them. The mixing happened mainly about 50,000–45,000 years ago, leaving roughly 1–2% Neanderthal DNA in non-Africans today, including genes affecting immunity and skin.
When and how
Probably western Asia and Europe, about 50,000–45,000 years ago; revealed by genetic work from Svante Pääbo's team and others.
How we know
Neanderthal DNA segments in modern genomes, and in early modern humans such as a man from Oase, Romania, who had a Neanderthal ancestor four to six generations back.
Debates and open questions
How often, where and under what circumstances groups met is unknown; earlier contacts also left modern-human DNA in Neanderthals.
▸Out of Africa migration led to Settlement of AustraliaMostly agreed
The connection
The migrants followed coasts across southern Asia toward Southeast Asia. With low sea levels, Indonesia's islands were closer together, but reaching Sahul, the joined landmass of Australia and New Guinea, still took several sea crossings. Arrival by 50,000 years ago makes Australia one of the dispersal's earliest destinations.
When and how
From Southeast Asia through the islands of eastern Indonesia, by about 50,000 years ago, possibly 65,000.
How sure are we?
Dated archaeological sites in Australia, and DNA showing Aboriginal Australians and Papuans descend from the same out-of-Africa population as other non-Africans.
Debates and open questions
Whether people took a northern route via Sulawesi or a southern one via Timor, and whether there was one founding group or many, is unknown.
▸Out of Africa migration led, via Siberia, to Settlement of the AmericasMostly agreed
The connection
Descendants of the out-of-Africa migrants spread across Asia into Siberia. One population probably became isolated in Beringia, the land bridge to Alaska, for thousands of years during the coldest part of the Ice Age, then moved south into the Americas, the last continents people settled.
When and how
Siberia and Beringia, roughly 25,000–16,000 years ago.
How sure are we?
DNA from living Native Americans and ancient remains, including a 24,000-year-old boy from Mal'ta near Lake Baikal whose genes link Siberians and Native Americans.
Debates and open questions
How long this 'Beringian standstill' lasted, or whether it happened at all, is debated, along with how early the first people reached the Americas.