Modern humans now permanently live on every continent except Antarctica, but it wasn’t always this way. After our species, Homo sapiens, emerged in Africa at least 300,000 years ago, some eventually ventured out, trekking and voyaging across the world.
So when did the first modern humans reach each of the seven continents?
Out of Africa
The accepted ideas about human evolution today are the “Out of Africa” theories, which propose that H. sapiens evolved in Africa and spread to the other continents, sometimes displacing or mating with other members of the Homo genus — known as hominins — as they did so.
Some scientists once considered the “multiregional” hypothesis (also known as the “candelabra” hypothesis) which proposed that H. sapiens also evolved in other places, including in Europe and Asia. But the multiregional hypothesis is now rejected, said paleoanthropologist Michael Petraglia, director of the Australian Research Centre for Human Evolution at Griffith University in Brisbane.
“There is no support for the multiregional or candelabra model of human evolution,” he told Live Science. “All evidence points to the origin and movement of Homo sapiens out of Africa.”
According to recent studies, H. sapiens evolved from earlier hominins in Africa about 300,000 years ago, and our species first dispersed from there about 200,000 years ago, or roughly 100,000 years after it evolved, Petraglia said.
Related: When did Homo sapiens first appear?
Into Asia
Our species first spread from Africa into the eastern Mediterranean region, probably through the Sinai region between Egypt, Jordan and Israel. Although the Sinai is a desert now, scientists think it was much greener when anatomically modern humans first traveled there.
Another hypothesis suggested early modern humans migrated from Africa via a land bridge at the southern end of the Red Sea, across the Bab el Mandeb (Arabic for “Gate of Grief”) and into the Arabian Peninsula, which is also thought to have been greener hundreds of thousands of years ago. A study published in 2006, however, established that there had been no such land bridge. But the researchers noted that the Bab el Mandeb had always been only a few miles wide, and so it was possible that people had floated or paddled across.
From the eastern Mediterranean, H. sapiens quickly spread east into Asia. Petraglia told Live Science in an email that multiple waves of early humans may have established themselves along the nearest coastlines of Asia by more than 100,000 years ago, then moved into its interior regions. Between 54,000 years ago and 44,000 years ago, some H. sapiens bred with Denisovans, another early human species, and so gene variants from Denisovans now appear in the genomes of many Asians.
Into Europe
The earliest evidence of H. sapiens in Europe is from Apidima Cave in southern Greece and dates to about 210,000 years ago, Martin Richards, an evolutionary geneticist at the University of Huddersfield in the U.K., told Live Science. But if that dating is accurate, it may be from a very early wave of migrating H. sapiens that died off or retreated during a glaciation, he said in an email.
Scientists generally accept that our species arrived in Europe permanently between 50,000 and 60,000 years ago and that, during this time, they bred with and replaced the existing population of their close cousins, the Neanderthals.
Into Oceania
Mitochondrial DNA dating has indicated that H. sapiens arrived in Southeast Asia about 60,000 years ago, Richards said. From there, they spread into the prehistoric Sunda and Sahul regions that became Southeast Asia and Australia, which were mostly dry land at that time.
Archaeological evidence indicates that modern humans were in the New Guinea region up to 50,000 years ago. Scientists now think they spread from there throughout the Pacific Islands in waves of migration that included the Lapita expansion about 3,000 years ago and the Polynesian expansion from about 1,500 years ago.
Into North America
The leading theory of the origins of Indigenous North Americans was once that “Paleo-Indian” people had arrived about 13,000 years ago from Siberia by traveling over a land bridge called Beringia, to Alaska. But archaeologists have now discovered evidence of pre-Clovis settlements and even older human footprints from New Mexico that suggest the first North Americans arrived by that route, and perhaps along the Pacific coast, at least 23,000 years ago.
Into South America
Archaeological and genetic evidence indicates early modern humans spread from North America through Central America to South America, where fossils and archaeological artifacts suggest they’d arrived by about 15,000 years ago; the well-studied site of Monte Verde II in southern Chile, for example, dates to about 14,550 years ago. However, some scientists debate the date of the first human arrival in South America.
To Antarctica
Conventionally, the first person in Antarctica was the American sealer and explorer John Davis, who reportedly reached the seventh continent in 1821. However, his claim is disputed. Instead, it might have been the Norwegian businessman Henrik Bull or the Norwegian explorer Carsten Borchgrevink, both of whom claimed to have gone there in 1895. There’s also an idea that early Māori sailed to Antarctica from New Zealand as early as the seventh century, but this is not accepted by many historians and scientists.
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