I remember listening to a genetics podcast and being puzzled by all this talk about "empty DNA." Was it related to what we used to call junk DNA in any way? Searching for it on DDG revealed nothing. When I went to the trouble of going back to the transcript the mystery was solved. It was mtDNA.
That's just an anecdote with a tenuous connection to my actual topic.
I was in a civil argument in a comment section about Cheddar Man. After some scrambling, we found we were both patiently explaining the same thing to each other. No harm done. The popular press, especially in the UK, is fond of relating the story that a local schoolteacher is related to Cheddar, which proves that people haven't moved around that much in England, or something. 8,000 years later, there are still descendants hanging around the Gorge. Except that's not what the relationship is at all. To oversimplify, they both have a mitochondrial DNA haplogroup of U5. That is the mother to daughter to granddaughter line of descent. You can find U5s at low concentrations all over Europe (and European descended). That they are both U5 doesn't mean they are that connected. It just means they have a common female ancestor 25-35,000 years ago. It's actually not quite that bad. They may have a similar subtype which arose only 17-27K y/a. But still, even though it is technically possible that Adrian Targett, the modern Englishman, is descended from some near relative of Cheddar's, it's a long shot.
To take my own example, I have mtDNA U3. U got named "Ursula" in The Seven Daughters of Eve that came out in 2001. Thus I have at least one ancestor in common with all the other U's in the world, wherever they may be. That one ancestor was over 6000 years ago and was somewhere in Western Asia, likely in what is now Iraq, Iran, or the Caucasus. A whole lot of gypsies (36-56%) have U3, and a fair chunk of Berbers (10%) as well. It is otherwise rare. But nothing remotely Roma, Berber, or West Asian shows up in my DNA, not even trace amounts. That is the maternal line, and I can trace that to SE Sweden in the 1700s. Not a gypsy in sight. They only arrived in Poland-Lithuania after 1500, so someone got herself sold, captured, or inveigled into Sweden within the next few generations. That's only a few hundred years ago, not 8,000, but it would still be silly to say that I am descended from gypsies. Or Berbers.
As for Mr. Targett, there are people all over Europe who are also U5, and by law of averages, lots of them are more closely related to Cheddar Man than he is. Interestingly, he himself is quite mystical about this, believing that the artist's re-creation of what the fossilised gentleman looks like resembles him remarkably.
2 comments:
You’re forgetting about pedigree collapse. https://www.scientificamerican.com/article/humans-are-all-more-closely-related-than-we-commonly-think/
Quote: “ In 2004 mathematical modeling and computer simulations by a group of statisticians led by Douglas Rohde, then at the Massachusetts Institute of Technology, indicated that our most recent common ancestor probably lived no earlier than 1400 B.C.and possibly as recently as A.D. 55. In the time of Egypt’s Queen Nefertiti, someone from whom we are all descended was likely alive somewhere in the world.”
At the 9th Millenium BC, that’s more than long enough for every modern person of English descent to be descended from Cheddar Man, if he was one of the lucky people who left descendants, and if his family line did not die out.
I have posted on that concept twice. https://assistantvillageidiot.blogspot.com/2005/12/pedigree-collapse.html.
If his line did not die out, then he is indeed the ancestor of all of us with English ancestry. But it is likely that his line did die out, because most do.
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