Scientists have found evidence of ancestral DNA in human genetic material, shedding light on our genetic composition. Researchers have detected DNA from two unidentified groups of hominis, a category of primates that includes homo sapiens and neanderthals. One group originated in Africa approximately 50,000 years ago, while the other ‘super archaic’ hominis lineage dates back 1.8 million years.
These ancient hominis are believed to have interbred with Denisovans, another extinct group, like neanderthals. The genetic mixing occurred in Eurasia, where Denisovans shared the ‘super-archaic’ DNA with homo sapiens thousands of years later. It is estimated that modern humans carry a similar amount of ‘ghost DNA’ as neanderthals, around 1 percent.
Yulin Zhang, a researcher from UC Berkeley involved in the breakthrough, stated, “We found that about 2 percent of the modern human genome comes from archaic hominins.” The study revealed that both modern-day Africans and non-African populations have inherited comparable amounts of ghost ancestry, with each individual possessing approximately 0.5 to 1 percent of their genome from this ghost lineage.
Arjun Biddanda, a postdoctoral researcher at Johns Hopkins University and study co-author, expressed excitement about the discovery of the super-archaic lineage contributing genetic material from over a million years ago. The research has shown that the presence of ‘ghost DNA’ is not limited to modern-day Africans but is equally present in both African and non-African populations, indicating extensive interbreeding before homo sapiens spread beyond Africa.
These findings support the theory that modern humans are a blend of genes from extinct hominis groups, suggesting prolonged interbreeding over millennia to shape the genetic diversity seen in present-day humans.