Jones-Corken Double Cousins

What is a double cousin?

It’s when first cousins share all four grandparents, not just one set of grandparents.  This happens when two siblings marry two siblings from another family.  Imagine a young lady marrying a guy and then introducing her sister to her husband’s brother.  If both marriages produce children, those children are double first cousins.

This is important genetically because double first cousins share twice the average amount of DNA that first cousins would normally share.  First cousins typically share 12.5% of their DNA, but double first cousins share 25%.  That is equivalent to the genetic relationship shared by half-siblings or grandparents-grandchildren.  (The percentages are averages; individual relationships vary.)

The children of double first cousins become double second cousins, and their grandchildren become double third cousins, and so on.

Double first cousins are much less common today because families are smaller and people have more options than 200 years ago.  It was common in pioneer days because there were limited marriage options; you tended to pick from among nearby families.

The most prominent example in my tree resides in my paternal Jonnes/Jones line.  The relevant couples are:

1. Thomas Jones (1766-1849) and Elizabeth Cox (1765-1847)
2. Robert Corken (1762-1844) and Grace Mason (1754-1837)

Both couples are fourth great-grandparents (4GGs); all four were born between 1754 – 1766 and died between 1837 – 1849.

The Jones and Corken families were pioneer neighbors in Ross County, Ohio in the early 19th century.  Thomas Jones migrated from the vicinity of Evesham, Burlington, New Jersey to Liberty Township, Ross, Ohio in 1804.  Robert Corken migrated earlier, arriving in Ross County, Ohio in 1798 from northern Maryland.  He settled in Springfield Township.^[1]Details of Robert Corken’s migration and early settlement history may be found here.

I believe the two families lived only 2 or 3 miles apart, and possibly closer, although I have never been able to precisely locate the Corken property.  The Joneses lived along Walnut Creek right next to Rattlesnake Knob, a prominent hill, near the intersection of Liberty, Springfield, and Harrison townships.

A large number of the (Thomas Jones descendants) located in that section of Ross County, and the place of their location was long known as the Jones Settlement.^[2]Lyle S. Evans, “A Standard History of Ross County: An Authentic Narrative of the Past … Volume II” (Chicago: Lewis Publishing, 1917), p. 932.

The Corkens lived upstream from the Joneses, also near Walnut Creek, but north of them in Springfield Township.

The relationship between the two families must have been amicable because 3 of their children – not just 2 – married each other.

Three Jones-Corken unions:

• William Jones (1788-1874) and Jane Corken (1792-1856), married 1812
• Henry Jones (1791-1871) and Rachel Corken (1796-1893), married 1816
• Rebecca Jones (1800-1865) and Thomas Corken (1792-1882), married 1819

The second couple, Henry & Rachel Jones, are my 3GGs.  All the descendants of the first and third couples are double cousins to me.

The three marriages produced huge families by today’s standards.  By my possibly incomplete count, there were 31 offspring beget from the three unions, at least 21 of whom lived to adulthood and had children of their own.^[3]All may be viewed in my public tree on Ancestry.com, Jonnes Family Tree, with sourcing.  I have not fully researched all the offspring, so I could be missing additional children.  Thomas & … Continue reading

The above chart lists by name the 21 known Jones-Corken double first cousins who married and had children.  The total number of double second cousins produced by these Double 1Cs is shown at the bottom of the chart.  William & Jane Jones, Henry & Rachel Jones, and Thomas & Rebecca Corken shared 118 grandchildren!  (47 + 45 + 26).^[4]Again, this is a rough number.  There were at least 118 grandchildren, but I am probably missing a few, and some did not live to adulthood or have offspring.

Several surnames other than Jones and Corken begin to appear as the females among the Double 1Cs married into other families: Van Gundy, Mendenhall, Johnston, Davis, Hanna, Noffsinger, and Terhune.

Note that two of the three daughters of William Jones & Jane Corken married Van Gundy brothers, and all three of the daughters of my 3GGs Henry Jones & Rachel Corken married Johnston brothers, another indication of how common it was for siblings to marry the siblings of another family in those days.

Many of these double cousins and their descendants remained in Ross County, Ohio for decades, especially Chillicothe, even up to today.  Many now live in the Columbus, Ohio metropolitan area.

However, a large contingent of Jones and Corken families moved west to Nodaway County, Missouri in the 1860s and 1870s.  They primarily settled in the jurisdictions of Burlington Junction and Green Township.

The migration began in 1860 when one of the 21 double first cousins listed above, Samuel Corken (1837-1918), contracted with his brother-in-law Col. John H. Davis to drive 12 thoroughbred Durham cows from Ohio to Missouri – a journey of 800 miles – where he settled.  His brother Henry Corken (1820-1905) and their widowed father Thomas Corken followed in spring 1862.  The Homestead Act of 1862 may have been the impetus for this move because Henry Corken later obtained a homestead patent in Nodaway County, Missouri.^[5]Henry Corken, (Nodaway County, Missouri), homestead patent no. 399; “Land Patent Search, digital images, General Land Office Records (www.glorecords.blm.gov/PatentSearch : accessed 22 March … Continue reading

This plethora of double cousins partially explains why I have so many Jones-line DNA matches.  When I compare how many DNA matches belong to each of my ancestral lines, my Jones matches are near the top of the list.^[6]Jones-Corken matches are in the top 4, along with 3GG Matthews-Brown, 3GG Vermilyea-Mead, and 2GG Blalock-Kennelly.

The ThruLines tool on AncestryDNA lists 45 DNA matches who are Jones-Corken double cousins.  The amount of DNA shared is typically 30 – 70 cMs.  These matches are most commonly Double 5Cs or Double 5C1Rs, although I have a few who are Double 4C1Rs.  All descend either from the union of William Jones & Jane Corken (21) or Thomas Corken & Rebecca Jones (24).  According to the Shared cM Project 4.0,^[7]Blaine T. Bettinger, Shared cM Project Relationship Chart, www.thegeneticgenealogist.com., 5Cs share 25 cM on average, so these amounts are roughly double that, as expected.

I have many additional AncestryDNA matches who likely are Jones-Corken double cousins even though they are not captured by the ThruLines tool, which relies on customers attaching family trees to their DNA accounts.

One DNA match really jumps out.  Let’s call her Lola.  Lola and I share 129 cMs, by far the most of my Jones-Corken double cousins.  Genealogically, we’re 5Cs, but genetically we are much closer.  In fact, 129 cMs is so large that it is beyond any 5Cs ever recorded by the Shared cM Project.^[8]The range for all 5C relationships in the Shared cM Project is 0 – 117 cMs.  Of course, Lola and I are not simply 5C, but Double 5C.  I assume that the Double 5C centimorgan average would be about 50 cM, a doubling of the 25 cM average for 5Cs.  Even then, 129 cMs is extremely high.

When I looked at Lola’s tree more closely, I discovered she and I have an additional genetic connection.  As a Double 5C to me, she is descended from Thomas Corken & Rebecca Jones.  However, she is additionally descended from Henry Jones & Rachel Corken via their son Henry Jones Jr.   This is possible because her great-grandparents were Jones-Corken second double cousins when they married each other!  Maybe I should call her a double-double cousin!  Genetically, the marriage of second double cousins is equivalent to first cousins marrying each other.