Recent mitochondrial DNA studies have established that all domestic golden hamsters are descended from one female – probably the one captured in 1930 in Aleppo, Syria by Israel Aharoni, a zoologist and professor at the Hebrew University of Jerusalem.
In 1980, Wesley Brown noted that there were relatively few differences in the mtDNA of human beings, as compared to the levels of difference found in other primates – for example chimpanzees. This suggested that humans share a much more recent common ancestor than other primates do.
Human beings are not as closely inbred as domesticated hamsters – though in terms of the Natural World in general, there isn’t actually that much difference between hamsters and humans. Rather than best being characterized as mongrels we are more properly all classified (all 6-7 billion of us) as purebreds.
As most of us are already aware, all 6-7 billion of the human beings alive today share a male-line ‘Most Recent Common Ancestor’ or Concestor. This man has been termed the ‘Y-chromosomal Adam’. He probably lived between 90,000 and 60,000 years ago.
In non-scientific terms, Adam’s female counterpart is Mitochondrial Eve. She is estimated to have lived around 200,000 years ago. Unlike Adam, she is not a Concestor. This woman is 'simply' the most recent person to whom all people can trace their female-line genealogy. She is the actual matrilineal ancestor of us all. Since mtDNA are inherited maternally and recombination is either rare or absent, it is relatively easy to track the ancestry of the lineages back.
She wasn't the only woman alive when she was living - it is simply that of the women who were alive at that time, her mitochondrial dna best survived. And the dna of the other women didn't disappear - as it is non-mitochondrial it is simply not separately identifiable.
Rohde, Olson & Chang (2004) 'indicate that the overwhelming majority of humans have a recent common ancestor within the last 5000 years (albeit between any two individuals, it may not be the same ancestor), however the genetic relationship between well diverged individuals may not reflect the theoretical relationship, as geographic and cultural barriers may slow gene migration’.
Taking up this point, Richard Dawkins (The Ancestor’s Tale) makes some interesting general observations, using model estimates:
‘Everyone alive in the world at the time of Geoffrey Chaucer (say 1450) will have either the entire world population as descendants or no descendants at all’.
‘The point in time at which everybody was either the ancestor of all modern British people or of none, is only about 40 generations, or about 1000 AD’.
And it only takes the construction of a very simple EXCEL spreadsheet to illustrate the explosion in the numbers of ancestors that we all have, as the generations pass. I have done this below, basing it on my own birth date 1944:
Birth-Generation-Numbers of Ancestors
1944-1-2
1917-2-4 (Father born 1909, mother 1915)
1890-3-8
1863-4-16
1836-5-32 (All 32 great, great grandparents identified)
1809-6-64
1782-7-128 (Earliest paternal ancestor - Shorrocks)
1755-8-256
1728-9-512
1701-10-1,024
1674-11-2,048
1647-12-4,096
1620-13-8,192
1593-14-16,384
1566-15-32,768
1539-16-65,536
1512-17-131,072
1485-18-262,144 (Earliest relative - Lubbock)
1458-19-524,288
1431-20-1,048,576
1404-21-2,097,152
1377-22-4,194,304
1350-23-8,388,608
1323-24-16,777,216
1296-25-33,554,432
1269-26-67,108,864
1242-27-134,217,728
1215-28-268,435,456
1188-29-536,870,912
1161-30-1,073,741,824
1134-31-2,147,483,648
1107-32-4,294,967,296
1080-33-8,589,934,592
1053-34-17,179,869,184 (Norman Conquest)
432-57-144,115,188,075,856,000 (Anglo-Saxon 'Replacement' starts)
0-73-9,444,732,965,739,290,000,000 (The Roman World)
Of course, the reality is that we share our dna through 'diamonds' rather than constantly widening 'triangles'. This is because, beyond a certain point, the progenitors of one of our sets of ancestors also become the progenitors of another set of our ancestors. This is particularly true within geographically restricted ancestral homelands.
So, for example, both my father's father and my mother's maternal grandfather may also share an ancestry with Cardinal Wolsey.
A COMMENT
Thomas Lubbock is one of the earliest people who can be named in my Family Tree:
1.2.2.1.1a Thomas LUBBOCK*, 161
————————————————————————————————————————
Bapt: 18 Mar 1586/1587, Erpingham, Norfolk, England
30 Mar 1672/1673
Burial: 25 Oct 1673, Erpingham, Norfolk, England
Spouse: Mary WOLSEY, 162
Death: 1669
Burial: 14 Nov 1669
Marr: 27 Jun 1614
Now it is known that the Tudor-era senior public servant and mercantilist economist Cardinal Wolsey (he apparently spelt his name as Wulcy) originated in East Anglia. His family and a branch of mine therefore share a common geographic origin.
Thomas Wolsey was born circa 1471, the son of Robert Wolsey of Ipswich (1438–85) and his wife Joan Daundy. His father was widely thought to have been a butcher and a cattle-dealer.
Although he was a Catholic priest, Cardinal Tom had a long-term mistress Joan Larke who was born around 1490 in Yarmouth, Norfolk - another geographic link.
I have no hesitation then in claiming that I am directly related to Cardinal Thomas Wolsey, with the link being confirmed by the marriage of my ancestor Thomas Lubbock to Mary Wolsey in 1614.
On the other hand, we are talking links here within a body of between 500,000 and 1 million of potentially shared ancestors - many of whom, as we have noted, are surely cross-related both to me and to you.
My (& your) genealogical links to the Aleppo Hamster can also be similarly established though they are not quite so direct.
POSTSCRIPT
The fact that we are all genetically related in the not too distant past becomes very obvious in the case of famous people for whom cursory records and sufficiently creative research is available.
In the case of newly settled countries like the USA, the Founder Effect amplifies these linkages. Simply stated, the few early settlers have a proportionately greater influence on a population that is rapidly expanding from high rates of natural increase and high rates of immigration.
It is therefore quite possible that although, overall, the number of German immigrants to the USA exceeded the number of English immigrants, the proportion of the population that has one or more English ancestors is greater than the proportion that has one or more German ancestors.
Take President Barack Obama as an example.
It seems that through his mother Ann Dunham, President Obama can trace his ancestry back to Richard Singletary who was born around 1599 in England. When Richard’s son Jonathan moved from Massachusetts to New Jersey about 1665, he changed his name from Jonathan Singletary to Jonathan Dunham alias Singletary – for reasons unknown.
Ancestry details for Barack Obama compiled by William Addams Reitwiesner are available at:
http://www.wargs.com/political/obama.html
Overall, the genealogical research suggests that through his mother Stanley Ann Dunham, US President Barack is distantly related to U.S. Presidents James Madison, Lyndon Johnson, Gerald Ford, and former U.S. Vice President Dick Cheney. He is also apparently also related to British Prime Minister Sir Winston Churchill, U.S. Civil War General Robert E. Lee, and actor Brad Pitt, as well as Edward I of England (and through him to Queen Elizabeth II) - and Elvis Presley.
The President’s daughters Sasha and Malia Obama are eligible to join the National Society of the Daughters of the American Revolution (NSDAR) through 14 ancestors.
But then much of this (excluding the Revolutionary bit) applies to most of those who have English / UK roots of some kind. In fact it has been claimed that anyone who can prove an English ancestor living pre-1750, is inevitably related to the Royal Family.
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