How Close Were Our Distant Ancestors? Genealogy Takes a Look at Endogamy

 Nadene Goldfoot                                                

We know that when man first started, they lived in family groupings.  From a family, they would join another close family to become a clan, and so forth until it was large enough to be a tribe.  A tribe is a group of clans.                            

Looking at our origins, Abram, whose name became Abraham, had married his niece, Sarai, whose name became Sarah.  She was not only his niece but his wife and 1st cousin.

She took precedent over the wishes of her  Egyptian  handmaiden who had produced Abram a son when there was a conflict of interests. 

Their genes were from the same origins.  Abram's father was Terah, and Terah's father was Nahor I. Haran and Abram were brothers. Sarah's father was Haran  and Haran's father was Terah, and Sarah's brother was Lot.  Sarah's great grandfather was Nahor I.                                                   

They had a son named Isaac. Isaac  married Rebekah, daughter of Bethuel and sister of Laban.   Bethuel is the son of Nahor II. Nahor II is the son of Terah.  Rebekah  is Abram's grandniece and grandmother of Rebekah and Abram is her 1st cousin once removed.                                                 

  Terah, father of Abram and Haran and son of Nahor I, son of Serug.

In the account of Terah's family mentioned in the Book of Genesis (Genesis 11:26–32), Nahor II (Hebrew: נָחוֹר‎ – Nāḥōr) is listed as the son of Terah, amongst two other brothers, Abram and Haran (v. 26,27). ... Nahor married the daughter of his brother Haran, Milcah, his niece (v. 29).

                                                                         

My Family Tree Maker software program could not conceive of Isaac and Rebekah being related.  This was too much for it.  I checked and checked.  So maybe they have become a fairly good distance from each other.  I think the name, Milcah, threw it a punch, so I think I'll surprise it.    

Isaac:(father)  Abraham and Sarah, Terah and Amathlai, Nahor I and Iyoska, Serug and Milcah

Rebekah:(father) Bethuel, Nahor II and Milcah, Terah and Amathlai, Nahor I and Iyoska, Serug and Milcah

Serug and Nahor had married a Milcah, which is confusing.  

Serug (Hebrew: שְׂרוּג‎ – Śərūḡ, "branch"; Greek: Σερούχ – Seroúkh) was the son of Reu and the father of Nahor, according to Genesis 11:20–23. He is also the great-grandfather of the prophet and patriarch Abraham, thus the ancestor of the Ishmaelites and the Israelites.

In the Masoretic text on which modern Bibles are based, he was 30 years old when Nahor was born, and he lived for another 200 years, making his age at death 230. However, the Septuagint (LXX) and Samaritan Pentateuch texts state that he was 130 on fathering Nahor; the Samaritan Pentateuch gives his age at death as 230, stating that he lived another 100 years, while the LXX has 200, making him 330 at his death.

Further details are provided in the Book of Jubilees, which gives the names of his mother, Ora (11:1), and wife, Milcah (11:6). It also states that his original name was Seroh, but that it was changed to Serug in the time when Noah's children began to fight wars, and the city of Ur Kesdim was built, where Serug lived. It says this Serug was the first of the patriarchal line to abandon monotheism and turn to idol worship, teaching sorcery to his son Nahor.

We have 23 chromosomes, numbered from 1 to 23.  The 23rd determines sex, and is given the title of Y for male and X for female.

                                            

DNA is seen as a double helix, It's deoxyribonucleic acid, the blueprint of life, the sequence of chemicals that defines each of us as being unique, with the exception of identical twins who share the same genetic makeup.  

Here is a copy of a male and female 1st cousins on chromosome #1.they shared genes on 2 other places on #1 as well.  

Think of a chromosome as a yardstick that is numbered with cMs.

From point 26,748,812 to 43,705,961 measured 22.17cMs.  This cousin pair shared segments of genes on every chromosome except #13, 14, 16, and 20.  Chromosome #1 has the  most known genes (2,968) and the 23rd/Y chromosome has the fewest (231).  The total number of genes is estimated at 30,000.  It's not as close as siblings, but interesting enough.  

 Whether you belong to the line of Abraham and either his Egyptian Hagar or his relative and first wife, Sarah, your ancestors no doubt started the same way in a family group that became a part of a tribe somewhere.  Even the English started as tribes. 

 The tribe out of Abraham turned out to become 12 well-known tribes that could be called a nation, and was the 12 tribes of Jacob.  They were the basis for Israel.  Jacob's name was changed to Israel, but we still refer to him mostly as Jacob.  Names stood for certain things, like feats;  you do something fantastic and your title becomes your name.  This nation numbered 601,730 by the time Joshua and Moses had led them back to Jacob's old home of Canaan after being prisoners in Egypt for 400 years.  They had been Egyptian slaves with a certain slave mentality for so long that Moses deliberately took his time, 40 years, getting to Canaan, which wasn't that far away by 2021 standards, in order to turn them into a new people, prepared for what their future held.  

                                                                             

                                                          

Joshua was one among the many in  this group, and showed signs of bravery when he saw the Canaanites who were much larger and taller than the slaves, who must have been held on short rations, keeping them rather short, like what happened in WWII to people.  We see after a more nutritious diet, they produced much taller children.  So I imagine that's what happened to the slaves after 400 years.  Joshua saw the Canaanites, but he thought they could take them on if needed.  The other 2 spies sent with him were frightened when they saw their height.

                                            

 Joshua was from the tribe of Ephraim and he was the dispenser of where each tribe would live, so he placed Ephraim next to Judah, the largest tribe with 76,500 people.  Ephraim had 32,500.  They had lost 8,000 people in the 40 year Exodus, while Judah had lost only 1,900. 

 The 12 tribes would become a nation after many years when Saul, son of Kish of the tribe of Benjamin in the 11th century BCE was selected by the prophet, Samuel to be their king.  

By then there was a pretty good admixture of genes among the people.  Their future was to remain an endogamous people, however, putting to good use some very popular genes.

Endogamy is the practice of marrying within a specific social group, religious denomination, caste, or ethnic group, rejecting those from others as unsuitable for marriage or other close personal relationships. Endogamy is common in many cultures and ethnic groups. 

                                                  

Endogamy, also called in-marriage, custom enjoining one to marry within one's own group. The penalties for transgressing endogamous restrictions have varied greatly among cultures and have ranged from death to mild disapproval. When marriage to an outside group is mandated, it is referred to as exogamy.

The nation of Israel came up with rules about how close in relationship one could NOT marry.  So have nations of today. In the United States, second cousins are legally allowed to marry in every state. However, marriage between first cousins is legal in only about half of the American states.Oct 16, 2019

 In Judaism, the rules:  People we don't marry:

(a) His mother, grandmother and ascendants; the mother of his grandfather; his stepmother, the wife of his paternal grandfather, and of his ascendants; and the wife of his maternal grandfather.

(b) His daughter, granddaughter, great granddaughter and her descendants; his daughter-in-law; the wife of his son’s son, and descendants; and the wife of his daughter’s son.

(c) His wife’s daughter or her granddaughter and descendants.

(e) His sister, half-sister, his full or half-brother’s wife (divorced or widowed) except for Levirate marriage with the widow of a childless brother, and the full or half-sister of his divorced wife in her lifetime.

(f) His aunt, and uncle’s wife (divorced or widowed), whether the uncle be a full or half-brother of his father or mother.                                        

Icelanders love keeping track of how they're related, which has made them "the world champions of human genetics.” There are only 320,000 people who live in Iceland, and most are descended from a small clan of Celtic and Viking settlers. Thus, many Icelanders are distant (or close) relatives. Sometimes too close.  The national preoccupation with heredity has yielded an unexpected professional benefit: Concerns about wading into the shallow end of the gene pool are just a small part of the Icelandic obsession with genealogy. As Iva Skoch explained in Global Post, when two Icelanders meet, the first question is usually, "Hverra manna ert bu?" (Who are your people?) Bookstores are stocked with thick volumes on the histories of Icelandic families.“Having the genealogy of the entire nation is one of the things that has turned us into the world champions of human genetics.”  I believe they all check their genealogy out before marrying to see if it's okay.

                                                       
                              Abraham given Hagar by his wife, Sarah  

While parental consanguinity is known to increase the risk of birth defects in offspring, it is hard to quantify this risk in populations where consanguinity is prevalent.  Consanguinity is the characteristic of having a kinship with another person. Many jurisdictions have laws prohibiting people who are related by blood from marrying or having sexual relations with each other. The degree of consanguinity that gives rise to this prohibition varies from place to place.                                             

Where our ancestors really had no choice in the matter due to lack of a population in those days, they had smaller box of genes as well.  We've accumulated many more in our choice of producing children, I would think.  We're carrying genes from well over 4,000 years of accumulation of fairly recent times. 

What counts are the genes we've picked up in the last 1,000 years.   Think of it.  Homo Sapiens have been around for H. sapiens is very recent, having originated in Africa more than 315,000 years ago (315 kya).  Thank goodness those genes haven't popped up.  Scientists today can find our very ancient genes in GedMatchgenesis.com  They have the tools for us to use and discover our origins.  

Resource:

https://pediaa.com/what-is-the-difference-between-tribe-and-clan/#Tribe

https://www.britannica.com/topic/endogamy

https://www.chabad.org/library/article_cdo/aid/468337/jewish/Prohibited-Marriages.htm

https://genetics.thetech.org/ask-a-geneticist/can-you-marry-cousin

DNA & Genealogy by Colleen Fitzpatrick & Andrew Yeiser

http://www.increasinglearning.com/blog/population-abraham