For decades, it has been widely-accepted that modern humans (Homo Sapiens) evolved in Africa, and then escaped and conquered the rest of the world around 70,000 years ago. But certain evidence may be calling this model into doubt.
Rethinking Early Migrations
Years of genetic and archaeological evidence have made the “out of Africa” model a forgone assumption. For instance, all living humans can trace their DNA back to a “Mitochondrial Eve” and “Y-chromosome Adam” who lived somewhere in Africa over 200,000 years ago (though not together).
Our predecessors then made their way out of the continent in two distinct waves, the first some 120,000 years ago, and another 70,000 years ago. This second wave went on to conquer the rest of the world, or so the story goes.
But despite the overwhelming scientific consensus, critics of this theory remain. Bruce Fenton, author of The Forgotten Exodus Into Africa, believes that 70,000 year ago, modern humans actually made their way back into Africa, not out of it.
Fenton points out that supposed modern human teeth dated to a 120,000 years ago were found in China, and other finds place our species in Australia as early as 80,000 years ago. The generally accepted timeline, of a human exodus from Africa around 70,000 years ago, cannot explain these findings. Other scientists, however, argue that these finds belong to different, “pre-human” species.
Is DNA Evidence Admissible in Anthropological Court?
Fenton also points out that there is no way to know for certain that our mitochondrial and Y-chromosome lineages (i.e. Eve and Adam), also known as haplogroups, actually originate in Africa. One such group previously believed to be African in origin, L3, is now suggested to have actually originated in Asia.
This “exodus” back into Africa coincided with many cultural developments such as the first signs of art and advanced hunting technologies like the bow and arrow. Could it be that people from Asia came back to Africa and brought their genes and ideas with them?
Finally, Fenton points out that around 70,000 years ago, when humans were hypothesized to have escaped Africa, the climate in North Africa and the Middle-East would have been especially harsh, making it unlikely for people to cross.
A New Theory
Fenton believes the “Out of Africa” theory as it stands today has more holes than swiss cheese, so he has proposed a new one.
He believes that the first migration, around 120,000 years ago, which was previously thought to have remained in the Near East, may have actually made it as far west as Australia.
Keep in mind that at that time, sea levels were far lower, so the Australian continent may have only been some hundred miles off the coast of Indonesia, which itself was connected by land to the rest of Asia. A few controversial archaeological findings, like shell factories or firesticks, suggest that people may have lived in the region that early.
Others argue these are natural produced artifacts, not of human origin. Anthropologist Tim Ryan of Penn State said, “there does not appear to be any good evidence of modern humans in Australia until around 50,000 years ago.”
The Volcano That Rocked Our World
Fenton’s supposed intercontinental human community did not last long. Around 73,000 years ago, the Lake Toba supervolcano erupted on the island of Java, spewing tons of toxic dust into the atmosphere. We know that the eruption drove many animals extinct. We also know that humans could’ve ended up among them.
Genetic analysis indicates that around this time, the entire human global population underwent a bottleneck, and was reduced to only about 10,000 individuals.
Fenton believes the surviving individuals escaped to either southern Africa or southeast Asia in order to survive the ensuing Ice Age. The Asian populations moving back into Africa may have brought with them their genes and inventions.
Weaving A New Theory
Fenton‘s theory, as outlined in detail in his book, has received the support of a few experts, such as anthropologist Michael Carmichael, who said it “may reshape the scientific understanding of human evolution.” However, Fenton also admits that he has encountered a lot of pushback.
Anthropologist Tim Ryan says, “while there may have been pulses out of Africa, it doesn’t seem like a widespread dispersal happened until 50,000 years ago.” In essence, there simply isn’t enough convincing evidence to prove Fenton’s theory at the moment.
In explaining why so few have chosen to even consider his paradigm-shifting ideas, Fenton offers a quote from Tolstoy:
“I know that most men, including those at ease with problems of the greatest complexity, can seldom accept even the simplest and most obvious truth if it be such as would oblige them to admit the falsity of conclusions which they have delighted in explaining to colleagues, which they have proudly taught to others, and which they have woven, thread by thread, into the fabric of their lives.”
Perhaps new evidence in the years to come will help us “weave” a better explanation for the early migrations of our species.
But for now, we must remember that science, like humanity, is constantly evolving.