One of the more shocking breakthroughs evolving from genomic sequencing of ancient hominin DNA is the realization that all human beings outside Africa have remnants of DNA in their genomes that don't belong to today's human species.
The roughly six billion people here on Earth whose current ancestry does not belong to Africa must have inherited between one and two percent of their genome from our closest though now extinct ancestors: the Neanderthals.
In connection to this, the Oceanians and the East Asians have also gotten a small degree of ancestry from the Denisovans, the Homo Sapiens' another close relative.
To date, a new study, which Science Advances published, recommends that ancient people who lived in Africa may also have reproduced with old hominins. Essentially, these are non-existent species related to Homo sapiens.
Additionally, the interbreeding outside Africa took place after the Homo sapiens ancestors, according to Heritage Daily, "expanded out of Africa into new environments."
It was the place where they had sex with Neanderthals, as well as the related Denisovans. More so, such mating has led to new and fresh discoveries.
What Happened Inside Africa?
It's undoubtedly thinkable that anywhere between 92 and 98.5% of the origin in humans who don't live in Africa at present does definitely arise from the expansion outside Africa.
However, people know now, the remnants came from ancient species whose descendants left Africa hundreds and hundreds of years before that. Intuitions into reproducing have been led by the ancient genome's much greater availability from outside of Africa.
This is because both Eurasia's dry and cold environments are far better at the preservation of DNA, tropical Africa's wet heat.
However, one's understanding of the connection between the olden human ancestors within Africa, as well as their link to ancient humans starts to deepen.
In a study of ancient DNA from southern Africa in 2017, it was investigated that 16 ancient genomes from people living over the last 10,000 years. This indicated that the African population history was complex. More so, the history of African populations was complex.
There was not only a single human group across Africa when they came into expansion about 10,000 years ago.
Potentially Gene-Flow from an Archaic Predecessor
Seemingly now, that there was possibly gene-flow into the olden African Homo sapiens population that there was potentially gene-flow into ancient African Homo sapiens populations from an ancient descendant.
One of the ways in which this can happen is for the people to expand outside Africa, have Sex with the Neanderthals, and migrate back to Africa.
Certainly too, this has been, this has been exhibited in one of the recent studies.
The new study provides proof that there may have been gene-flow into the descendants of West Africans "directly from a mysterious archaic hominin."
In addition, the scholars compared the Denisovan DNA and Neanderthal, with that from four contemporary populaces from West Africa.
Utilizing some sophisticated mathematics, they then, develop a statistical model to further explain the relationships between the ancient hominins and modern Africans.
