Africa is the homeland of humanity – at least, that’s what most experts currently think. Like all families, Homo sapiens has a complicated story marked by disagreements, unanswered questions, and glaring gaps in our understanding.
The idea that all members of Homo sapiens (that’s us) can trace their ancestry back to Africa is known as the “Out of Africa” theory, which asserts that modern humans originated in Africa around 200,000 to 300,000 years ago and subsequently migrated around the world.
Today, this is the most widely accepted story, standing in contrast to the multiregional hypothesis that says we evolved simultaneously in multiple regions of the world from local populations of earlier human species. However, there is still a huge amount of debate and controversy within the broad church of “Out of Africa” advocates.
A contentious study published in the journal Nature in 2019 claimed the ancestral homeland of all humans alive today can be found south of the Zambezi River in present-day Botswana, southern Africa.
The researchers reached this conclusion by looking at the earliest-known branch of human maternal DNA, called the L0 mitochondrial DNA lineage, in 1,217 people from southern Africa.
By combining the genetic evidence with linguistic, cultural, geological, and archaeological data, they pinpointed the location to the Makgadikgadi-Okavango paleo-wetland. The region, now dominated by deserts and salt pans, was once the site of a massive lake more than twice the size of modern Lake Victoria. Around 200,000 years ago, this lake broke down to form a sprawling, lush wetland.
According to the study, early modern humans settled in this fertile, green environment and remained there for 70,000 years before climate changes prompted their dispersal.
Humidity increased in the surrounding area, creating “green corridors” that allowed humans to migrate first to the northeast and then to the southwest. From here, they continued to expand across much of Africa and, eventually, into Eurasia.
The study was widely publicized, including by IFLScience, although some scientists rejected some of the researchers’ bolder claims. By doubting some of the conclusions drawn from the limited genetic analysis, certain experts felt it was unlikely all our genetic ancestry could be tracked to one small homeland.
While this genetic data suggests the “cradle of humanity” is in southern Africa, most of the early skeletal evidence suggests an eastern African origin, especially in present-day Ethiopia. Many significant remains of Homo sapiens have been found in the Horn Of Africa, plus this region also holds plenty of evidence of earlier, now-extinct human species, suggesting it was an important region for our species’ heritage.
Unexpectedly, the oldest Homo sapiens remains on record were unearthed in Morocco, dating to around 315,000 years old. However, few researchers would argue that our species emerged in North Africa. Alternatively, the Moroccan skeleton could show that early humans evolved across many different parts of the continent.
This might be the most balanced view: Homo sapiens did not emerge from one single population in one single homeland, like some kind of scientifically verified Garden of Eden. Instead, multiple populations of early humans were scattered across the African continent, interbreeding with each other at convenient intervals, creating a massively complex family tree that eventually gave rise to modern Homo sapiens.
We can see particular locations that were significant in the emergence of Homo sapiens – namely southern Africa and east Africa – but the family tree is ultimately too intertwined and fuzzy to unravel a single origin.
