While the scientific community has long believed that Native Americans ancestry is closely linked to various European peoples, an increasing number of studies suggest that these tribes may be a lot more diverse than previously believed.
One such study has found that certain Native Americans in the Amazon rainforest are at least partly descended from those living in the Pacific, in a region known as Australasia to be exact. The researchers have named the ancestors “Population Y”, and have yet to pinpoint the exact moment in time when they made their way to the Amazon or find an explanation for how they got there.
It’s an interesting finding as most studies conducted to this day have established that all Native American tribes share a common origin – they’ve all descended from a population in Euroasia. These ancestors are said to have migrated to the Americas roughly 15.000 years ago, a time when the Bering land bridge connected the continents.
Some Native American tribes living in North America and in the Arctic have also been shown to have inherited DNA from more recent migrations.
But certain past studies have also looked at the skull shapes of these tribes and found that two entirely different groups of ancestors may have entered the Americas. One closely resembles most of the modern day Native Americans, while the other one seems to be an earlier population that seems to share DNA with the Native Americans living in Brazil.
The second group closely resembles the modern day people living in Australasia, an area that incorporates Australia, New Guinea, New Zealand, as well as other adjacent Pacific Islands and even certain African groups.
A group of researchers set out to investigate the mystery and examined DNA samples collected from 30 Native American tribes from Central America and South America, as well as from 197 non-American populations across the world.
What they found was that certain Native American tribes living in the Amazon rainforest share some of their DNA with a population that is closely related to the Onge, a group from the Andaman Islands located in the Bay of Bengal (New Guineans), as well as indigenous Australians. In fact, they seem to have a lot more in common with these groups than they do with modern day Eurasian populations.
Pontus Skoglund, lead author and population geneticist from the Harvard School of Medicine (Boston), gave a statement saying that this finding was really spurring to him and his team.
He went on to add that while most genetic studies conducted to this day have concluded that all North Americans and South Americans have descended from the same ancestral source population, the new study contradicts this widely held belief. It concluded that the overall scenario is much more complicated than that.
The researchers informed that Native American tribes from North American and Central America do not share DNA with Population Y (short for Ypykuéra), which seems to suggest that these ancestors only passed on their genetic signature to the Amazonians, and did so long before the respective Native American tribes reached the Amazon rainforest.
But the researchers can’t tell exactly when Population Y shared their genes with the Amazonians. The lead author mentioned that “We cannot say much about the story of how this genetic link came about. This finding just raises more questions we need to answer about American history”.
The study is not the first one to reveal that American history is much more complicated than we believe. A 2013 study conducted by Brazilian researchers also discovered that an extinct Native American tribe had Polynesian DNA.
Image Source: thetimesgazette.com