Page 74 - The Ancestry of Francis Bryan (1770-1863)

MY GRAPHS: DNA PROJECT TWO
I devised a research project to assess the connections between the In Common With (ICW) matches shared amongst the descendants of my projected ancestors, specifically Thomas Bryan and William Bryan, Sr. and Margaret Strode. The matches are from Ancestry.com.
I was able to persuade descendants of Joseph, Morgan and Peggy Bryan to join the project, along with a few of Francis' descendants. I also had one descendant of William Bryan. This participant descends from William Bryan's daughter, Mary Catherine. DNA suggests a half sibling relationship between Mary Catherine and Margaret Strode Bryan. So the DNA matches from this descendant most likely only reflect a relationship to William Bryan and not to the Strodes.
There are a few things to note about this particular cluster graph before I continue. When you see it you will probably notice that there are very few discreet clusters. There are MANY, MANY interconnecting threads between the clusters. This type of clustering tends to denote quite a lot of intermarriage between relatively few families. The term for this is ENDOGAMY.
Here is the description of Endogamy from The International Society of Genetic Genealogists (ISOGG):
Endogamy is the practice of marrying within the same ethnic, cultural, social, religious or tribal group. In endogamous populations everyone will descend from the same small gene pool. People will be related to each other in a recent genealogical time frame on multiple ancestral pathways and the same ancestors will, therefore, appear in many different places on their pedigree chart. Endogamy can be the result of a conscious decision or cultural pressure to marry within the selected group but also occurs as a result of geographical isolation (for example, in island communities).
When I first began my research I was surprised to find a few first cousin marriages among the descendants of Francis Bryan and Phoebe Woodruff. Since then I have come to realize that it was a common practice in Colonial America. I have also come to realize that Francis and Phoebe's descendants were only mildly endogamous, especially when compared to the descendants of Francis' sister, Peggy!
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