Finding the boundaries is itself kind of a frontiering science, so I would say that makes it kind of a science and an art.
That quote came out of a recent news article about DNA testing. Surely it was taken out of context. So often quotes in the news are. However, I think it is good to address these things before they get repeated so many times that they turn into factoids.
Let’s start with the front part.
What are these boundaries?
They are fiction.
We are one human family.
In 2004, Rohde et al. wrote “These analyses suggest that the genealogies of all living humans overlap in remarkable ways in the recent past. In particular, the MRCA [most recent common ancestor] of all present-day humans lived just a few thousand years ago in these models. Moreover, among all individuals living more than just a few thousand years earlier than the MRCA, each present-day human has exactly the same set of genealogical ancestors.”
That means that every single person on earth alive today shares a common ancestor with every other person alive today. Further, that common ancestor was not in the far far distant past but lived only a few thousand years ago. It is only a little bit deeper in our ancestry that every one of us has the same set of common ancestors.
There are no boundaries. There is only one human race.
Yes, there are local geographic signatures. However, there is flow between every local population and its nearest neighbors. Trying to find false boundaries is what holds us back from better ethnic origins. When we accept our common ancestry and that all people alive today are recently interconnected, then we can more forward.
Now, the next part. It is kind of a science?
No. It is 100% science. Used well and within the limits of its capabilities, it can do a fine job. It is excelent at its intended purpose. It should be used carefully for ethnic origins. The science is very much real though.
Finally… An art?
No. It is not art. Anywhere the programs and the companies adjust results and call their methods art, they are pushing the science beyond its limitations.
More than anything, it is a matter of we, as humanity, shifting our perspective. We must be willing to accept what genetics is telling us. There are no cold hard lines. We are all connected. For a beautiful example of shifting perspective, here is a picture from Instagram [Logan James (@cctjoey) • Instagram].
Next time, I will talk about getting to genealogical grade ethnic origins results by using genealogical grade markers.
Posts in series
- PCA Based Ethnic Origins – Part 1, How it looks
- PCA Based Ethnic Origins – Part 2, What it was meant for
- PCA Based Ethnic Origins – Part 3, How it is used
- PCA Based Ethnic Origins – Part 4, Fixing the visuals
- PCA Based Ethnic Origins – Part 5, Science & not art
- PCA Based Ethnic Origins – Part 6, Genealogical markers
- PCA Based Ethnic Origins – Part 7, Autosomal SNP Genetics 101