Saturday, December 2, 2017

Isotopic Testing and Genealogy/ Marking DNA Matches at AncestryDNA

Poor Jane was eaten during the starving time


I visited Jamestown Settlement and Historic site last fall. Since many of my ancestors lived at some point in Virginia the history of that state fascinates me. Also it was thought my ancestor Francis Browning may have descended from Jamestown settlers?

I really enjoyed my visit to these Jamestown sites. I wanted to learn more about the Jamestowne Historic site so I'm currently reading "Jamestown the Buried Truth" by William M. Kelso, Jamestowne archaeologist. The similarities between genealogy and archaeology became very apparent to me reading this book. Archaeologists dig down through layers of earth each layer representing a particular time period. The deeper they dig the farther back in time they go. Same with genealogists, our layers being generations. Some new genealogists tend to miss the layering and connect the wrong generations.


Two of my goals have been to find the place of origin in Europe of my ancestors, and find out when some of these earliest families arrived in America. I have not been able to actually pinpoint an exact place of origin for any British Isles/Irish ancestors, except possibly the Forgeys in Co. Louth, Ireland? All of my British Isles ancestors appear to have come to this country before the American revolution.

 
Here is a chart with the earliest dates in America of my British Isles/Irish ancestors. Many appear to have Scottish or Scots/Irish roots based on their settlement on the frontiers, and their Presbyterian religion. Campbell is definitely a Scottish surname.
I have no idea when these particular ancestors arrived and from where?


The Thurmond relatives here are just speculative

My dead end regarding the origins of these families sparked my interest in the information found in teeth and bone analysis at Jamestown. How can teeth and bone help pinpoint where in the British Isles an ancestor came from? An explanation from Jamestown scientists,"Oxygen isotopes are stored in our teeth in childhood and can be used with other information to determine where a person grew up." This test gives an approximate locations such as Wales, as a place where someone lived as a child.

A test on bones can tell us about the diet of the deceased. If a persons diet had been corn for a time period before their death that can be detected using the chemical composition testing. Skeletons with a corn based diet either were Europeans who had been in America for some time or Native Americans. Those with wheat based diets, according to these tests, died soon after arriving in America.

It is exciting to know that if the remains of our early American ancestors are still available that we can learn more about their origins through teeth and bones. Unfortunately for me and other genealogists finding and unearthing remains is generally impossible. But who knows maybe an archeologist will unearth some of their remains at some point? If you are related to those skeletons found at Jamestown you could be in luck. You could find yourself related to the Bartholomew Gosnold who has had an mtDNA test performed on his remains.

Marking My Ancestry DNA matches

I decided to mark every DNA match at AncestryDNA I could identify a relationship with. Marking them with notes and stars. I basically identify them based on our most recent shared ancestral couple or a single ancestor. With couples I record the husband's surname first, a slash mark, then the wife's surname. If I know which of the couples children we relate through I record their first name. The second match, first column left, below, descends from Andrew Forgey and Margaret Reynolds through their son John. The estimate of 5th through 8th cousins would be correct. They would be 6th cousins, or 5th cousins once removed.


The names with questions marks generally mean this match doesn't have a tree, and I'm basing their relationship on shared matches. I only base relationships on shared matches if they share more than one common match with us. Sharing one common match is often a coincidence.

By catching up on marking identifiable matches searching by surnames I can separate them from my brickwall lines. If I search Campbell, for instance, and find a new match on that surname, and they have a very small tree I can might be able to eliminate them as descending from my Campbells using notes and shared matches. If this Campbell shares 5 Roller matches I can fairly confidently eliminate them as matching through Campbell. If they share one Roller match I wouldn't eliminate that possibility.

Out of around 11,000 matches for my late mother I was able, to some degree, identify the possible common ancestors for around 200 matches. Most of these are on well documented lines. The more surviving documentation, the longer the family has been in America, the number of trees online all seems to correlate with a high number of identified atDNA descendants and matches.

I don't think I was clear in my last blog post regarding finding the origin of atDNA segments. I'm not looking for the ultimate origin of segments, I'm actually looking for more recent origins at around the limit for the effective use of atDNA for genealogy; at round 5 or 6 generations.

By the way I downloaded the 11,000 matches with the chromosome browser extension AncestryDNA Helper. It would be great if we could download our matches and notes right from Ancestry. Using a browser extension, or downloading other applications, can be risky and infect your computer with malware or a virus. I have not had a problem with AncestryDNA Helper so it appears to be safe.

Since I can't dig up the ancestors I will return my focus to documents and DNA in 2018.







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