That "Dark Age" DNA of Scotland article is out, and I read it so you don't have to. There is no relationship between these modern clusters and the DNA of Picts (etc) because as yet no aDNA from these regions is available, and also because there is no such thing as a Pictish gene.
Of course, aDNA from populations across Scotland has been acquired and we await results of this work. But can we please agree a few ground rules before then.
In all cases, please wait for publication before the press release goes out. I know most people will not click through to it, but publication by press release is not a good look.
They acknowledge there are still many gaps (most of the Hebrides, and surprisingly most of the Lothians) in the dataset. For any future refinements of modern DNA, please note that the "Dark Ages" might explain the patterns you see. Other historical periods are available.
If you feel strongly that your algorithms point to a "dark age" explanation, please approach a relevant archaeologist or historian and include them in your process; better yet, approach one from the beginning to make sure your questions are the ones we still need answers to.
In discussing the significance of your 'dark age' results, avoid citing general works (Britain Begins, a great book but which flies from 10,000BC to AD 1066). Worse still, avoid citing a previous DNA study (Leslie et al 2015) for your historical background.
Once aDNA comes in, let's please avoid making it about races replacing each other, shall we? The way to do this is use neutral terminology to describe genetic clusters: https://dx.doi.org/10.1038%2Fs41598-018-31123-z …
However much we use scare quotes and italics in DNA studies, there's no avoiding that Celtic, Norse, English, British, or worse still England, Scotland, Ireland are all contemporary terms, with little if any 'dark age' meaning, so let's avoid any confusion and just not use them.
If you check any recent 'dark age' research, local specificity and variation, not ethnic essentialism, is where the discipline is. Rather than big data smoothing and filtering, we need mutlivariate, super-local studies with DNA, c14, stable isotopes, etc: https://doi.org/10.1038/s41467-018-06024-4 …
Personally I can't wait to be able to add aDNA to the well-established material culture and anthropological studies, refined statistical dating, and complex biological-molecular techniques, to make a rich, complicated textured vision of the 'dark ages', one individual at a time
Let's not tell century-old stories about when group A replaced group B. Even the story that we're all 'mixed' still assumes movement from purity to dilution (yuck). Read the scientific papers. Learn the limits of both DNA and archaeology. Work together. Tell a new story.
Keep the Dark Ages weird
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