[Reading Science] "Adam and Eve Did Not Exist"... The Declining Theory of a Single Origin of Humanity

International Collaborative Research Team Publishes Paper in Nature on the 17th
"Gene Flow and Local Population Formation Over Centuries"

"There was no Adam and Eve."

The conventional belief that modern humans originated from a single location in Africa is being challenged. By analyzing vast genetic data through computer models, it has been revealed that humans did not arise from one place but rather through mixing via various interactions over millions of years.

Homo sapiens fossil discovered in Morocco / Photo by CNN video capture

An international joint research team including the University of Wisconsin in the United States published these findings on the 17th (local time) in the international academic journal Nature. The study suggests that modern humans were not started from one place on the African continent but were born through exchanges among multiple populations scattered across various regions. Furthermore, these ancestral populations, estimated to have lived over one million years ago, were all from the same Hominin species but are presumed to have had slight genetic differences.

The research team developed new computer software and confirmed these facts by referencing genetic data from modern humans in Africa and Europe as well as DNA from ancient humans such as Neanderthals. Archaeogeneticists have spent decades trying to prove the "single origin theory." Fossils of ancient humans found in Africa were nicknamed "Adam," "Eve," and others, leading to numerous claims about pinpointing the origin of humanity. However, this single origin theory did not align with genetic analyses or archaeological excavation results. If humans had started from one region, older genetic data and artifacts would be collected closer to that place and fewer as the distance increased. However, in reality, physical features of Homo sapiens and the tools they used appeared simultaneously across the entire African continent during similar periods.

The team utilized software developed by Simon Gravel of McGill University in Canada, which has high-capacity computing power, to analyze vast amounts of genetic information. Previous studies lacked sufficient genetic data and mainly focused on data from West Africa, failing to reflect the extensive genetic diversity of the African continent. However, the research team integrated and analyzed broad genetic information from East and West Africa as well as the Nama people residing in Southern Africa. This method allowed them to track and understand how genes historically moved across generations. They also predicted gene flow over thousands of years considering migration and population merging. Notably, they identified the model that best matched the genetic variation seen in modern humans today.

Through this, the research team overturned the previous explanation that modern human genetic diversity was formed after Homo sapiens interbred with ancient species from different branches and then became isolated. Instead, ancient hominin species or human ancestors shared genetic differences and interbred over thousands of years within certain regions, forming localized populations. Over time, they migrated across the entire African continent. The research team named this finding the "weakly structured stem model" and stated that it can more reliably explain the genetic diversity of modern humans.