The Straight Dope

Go Back   Straight Dope Message Board > Main > General Questions

Reply
 
Thread Tools Display Modes
  #1  
Old 06-10-2010, 07:57 PM
Rigamarole Rigamarole is offline
Guest
 
Join Date: Dec 2005
Is Julius Caesar's bloodline traceable to present day?

Of course for the average mortal I would never expect to be able to follow a genealogy that far back. But for someone whose lineage was considered as important as Caesar's, one would think they would have made some effort to keep tracking it.

So are the modern-day descendants of Julius Caesar (if any exist) known? And if not, when did they lose track of them? During the fall of Rome? Who was the last known descendant?

Last edited by Rigamarole; 06-10-2010 at 07:58 PM..
Reply With Quote
Advertisements  
  #2  
Old 06-10-2010, 08:11 PM
Polycarp Polycarp is offline
Guest
 
Join Date: Aug 1999
Location: A better place to be
Posts: 26,718
There are genealogies that purport to trace ancestries back to Caesar. They are regarded by competent genealogists with a high degree of skepticism.
Reply With Quote
  #3  
Old 06-10-2010, 08:12 PM
Götterfunken Götterfunken is offline
Guest
 
Join Date: Jun 2002
I am not a classicist, but I think Caesar's bloodline died out with his two children--Caesarian (son of JC and Cleopatra) was assassinated when he was 17, and Julia died during childbirth, although her child lived a few days, so I guess it's more accurate to say the bloodline died out when Julia's child died.

Unless you mean the descendants of Augustus Caesar, whom JC adopted. If Wikipedia is accurate, then there's no way to answer your question--his line of descent can't be traced farther than the early 3rd century AD: http://en.wikipedia.org/wiki/Augustus#Descendants
Reply With Quote
  #4  
Old 06-10-2010, 09:15 PM
Shakester Shakester is offline
Guest
 
Join Date: Dec 2008
There isn't anyone who can realistically trace their ancestry back 2000 years. Reliable records - even in the most aristocratic families - don't exist before the renaissance.

Even if reliable records did exist, the amount of formal and informal adoption, passing off one man's children as another's, etc, means that after many generations, 100% of people are descended from someone different to the official version of their bloodline.

So, really, any of us with any possible European ancestry might be descended from Caesar, but nobody will ever know for sure because proving it is impossible. Even if we had a sample of Julius' DNA the amount of genetic drift that happens over 2000 years means that there is no possible way to definitively connect anyone from 2010 AD to any individual person from that era. The best you could say is "we can't rule out the possibility that you might be descended from the Julian clan."

Last edited by Shakester; 06-10-2010 at 09:18 PM..
Reply With Quote
  #5  
Old 06-10-2010, 10:02 PM
Rigamarole Rigamarole is offline
Guest
 
Join Date: Dec 2005
Quote:
Originally Posted by Shakester View Post
There isn't anyone who can realistically trace their ancestry back 2000 years. Reliable records - even in the most aristocratic families - don't exist before the renaissance.

Even if reliable records did exist, the amount of formal and informal adoption, passing off one man's children as another's, etc, means that after many generations, 100% of people are descended from someone different to the official version of their bloodline.

So, really, any of us with any possible European ancestry might be descended from Caesar, but nobody will ever know for sure because proving it is impossible. Even if we had a sample of Julius' DNA the amount of genetic drift that happens over 2000 years means that there is no possible way to definitively connect anyone from 2010 AD to any individual person from that era. The best you could say is "we can't rule out the possibility that you might be descended from the Julian clan."
Yeah, I kinda figured as much but wanted to see to what extent we really know of his line. I conceived of the question because I was having fun imagining how his descendants could be working in an Italian bakery, or American hedge fund managers, or in jail somewhere for child molestation and so on... anyway, could make an interesting fictional story.

So how did those records get lost? Like I mention in the OP I understand it for 99.9%+ of the population but it seems crazy that they couldn't even keep track of the people they considered to be so important that they were essentially divinities.
Reply With Quote
  #6  
Old 06-10-2010, 10:05 PM
Colibri Colibri is offline
SD Curator of Critters
Moderator
 
Join Date: Oct 2000
Location: Panama
Posts: 25,757
Quote:
Originally Posted by Shakester View Post
So, really, any of us with any possible European ancestry might be descended from Caesar, but nobody will ever know for sure because proving it is impossible. Even if we had a sample of Julius' DNA the amount of genetic drift that happens over 2000 years means that there is no possible way to definitively connect anyone from 2010 AD to any individual person from that era. The best you could say is "we can't rule out the possibility that you might be descended from the Julian clan."
Actually, at this distance in time it's a virtual certainty that anyone with any European ancestry is descended from Caesar's family (though not Julius, as his children left no descendants). This is due to pedigree collapse - as you go back in time, more and more of your ancestors are shared with others (see Cecil's column here). By the time you go back 2000 years, or around 100 generations, you are descended from essentially everyone who was alive in Europe at the time who has living descendants.

Last edited by Colibri; 06-10-2010 at 10:06 PM..
Reply With Quote
  #7  
Old 06-10-2010, 10:12 PM
YamatoTwinkie YamatoTwinkie is offline
Guest
 
Join Date: Apr 2008
If you figure about 30 years between generations, and two kids per generation, then there are about 2^(2100/30) = ~a sextillion descendents of Julius Caesar (or if not Caesar himself, then Caesar's cousin) alive today. Obviously, his family tree had some straight sections to it because that's more than the population of the planet, but still, the point remains, if you have *any* European blood, your chances are pretty good at being one of those descendents.
Reply With Quote
  #8  
Old 06-10-2010, 10:13 PM
Rigamarole Rigamarole is offline
Guest
 
Join Date: Dec 2005
Quote:
Originally Posted by Colibri View Post
Actually, at this distance in time it's a virtual certainty that anyone with any European ancestry is descended from Caesar's family (though not Julius, as his children left no descendants). This is due to pedigree collapse - as you go back in time, more and more of your ancestors are shared with others (see Cecil's column here). By the time you go back 2000 years, or around 100 generations, you are descended from essentially everyone who was alive in Europe at the time who has living descendants.
Good information. I wasn't really considering how exponentially we've been multiplying over all those years (thinking "how hard can it be to track one friggin' family?")
Reply With Quote
  #9  
Old 06-10-2010, 10:14 PM
Polycarp Polycarp is offline
Guest
 
Join Date: Aug 1999
Location: A better place to be
Posts: 26,718
For what it's worth, five alleged lines of descent of Queen Elizabeth II from Julia, sister of Julius Caesar. Take these, not merely cum grano salis, but with all the rock salt you have left over from last winter.

A lot of people can trace their lineage to Charlemagne, and there exists one documented line tracing his ancestry back to a provincial governor of some fame to specialist historians (Syagrius, if anyone cares) during the last days of the Roman Empire. But back beyond him? Legend and unproven lineages only.
Reply With Quote
  #10  
Old 06-10-2010, 10:22 PM
antonio107 antonio107 is online now
Guest
 
Join Date: Dec 2009
Quote:
Originally Posted by Rigamarole View Post
So how did those records get lost? Like I mention in the OP I understand it for 99.9%+ of the population but it seems crazy that they couldn't even keep track of the people they considered to be so important that they were essentially divinities.
The dark ages, while a misnomer, did represent a period in history when very little was written down. And if I'm not mistaken, didn't they use Papyrus for much of their written records? It has the bad habit of not weathering time very well...

As an Italian-Canadian, I'm not terribly convinced there's any Roman blood in me. My family was Abruzzese, so not getting into any north/south divide, I suspect that modern day Italians are more likely descended from Germans and Greeks than Roman Emperors. I have a better chance of being related to Odovacar or Attila the Hun than Julius Caesar.
Reply With Quote
  #11  
Old 06-10-2010, 10:22 PM
coremelt coremelt is offline
Guest
 
Join Date: Jan 2009
Quote:
Originally Posted by Polycarp View Post
there exists one documented line tracing his ancestry back to a provincial governor of some fame to specialist historians (Syagrius, if anyone cares) during the last days of the Roman Empire. But back beyond him? Legend and unproven lineages only.
who?
Reply With Quote
  #12  
Old 06-10-2010, 10:30 PM
Polycarp Polycarp is offline
Guest
 
Join Date: Aug 1999
Location: A better place to be
Posts: 26,718
Quote:
Originally Posted by coremelt View Post
who?
Charlemagne, mentioned in the previous sentence, if you mean who is the "his" in "his ancestry"; Syagrius, whose name I gave parenthetically, if you mean "traced to whom"
Reply With Quote
  #13  
Old 06-10-2010, 10:30 PM
Captain Amazing Captain Amazing is offline
Member
 
Join Date: Oct 1999
Posts: 23,259
Quote:
Originally Posted by coremelt View Post
who?
Sygarius was a Gallo-Roman ruler of the Domain of Soissons, which was a Gallo-Roman kingdom that rebelled against Rome and declared independence as the Empire collapsed. It lasted for about 30 years and then fell to the Franks.
Reply With Quote
  #14  
Old 06-10-2010, 10:32 PM
John DiFool John DiFool is offline
Guest
 
Join Date: Jun 2006
Isn't like 25% of all Central Asian peoples descended from Genghis Khan?
Reply With Quote
  #15  
Old 06-10-2010, 10:37 PM
antonio107 antonio107 is online now
Guest
 
Join Date: Dec 2009
Quote:
Originally Posted by John DiFool View Post
Isn't like 25% of all Central Asian peoples descended from Genghis Khan?
Supposedly. I missed that episode of 'Maury.'
Reply With Quote
  #16  
Old 06-11-2010, 10:51 AM
Shakester Shakester is offline
Guest
 
Join Date: Dec 2008
It's not proven that Julius' bloodline died out. His legitimate bloodline died out, but there is absolutely no way of knowing whether or not he knocked up a senator's wife and/or some random British slave girl and through her has millions of living descendants.

Over the course of 2000 years, the amount of surreptitious sex and unofficial adoption that has undoubtedly occurred in every family makes everyone's official ancestry fiction.

Nowadays we have DNA testing and can prove who is (or isn't) a child's father. A large percentage of the suspicions that lead to DNA paternity tests turn out to be well-founded. There is no reason to believe that today's women are any less faithful to their partners than the women of the past.

It didn't happen so much at the wealthier end of society, but plenty of men have married single mothers (or "widows", and occasionally genuine widows with children) and adopted and raised the non-biological child/children as their own, formally or informally. After a generation or two, who remembers that grandpa was adopted? Especially if it was done informally, as these things usually were in non-wealthy families. And especially if there was a hint of bastardy about it.

Orphans were and are routinely brought up by non-related people. If your sister and her husband die in a cholera epidemic but their baby miraculously survives, you take the baby in and raise it as your own. Or your teenage daughter gets knocked up by a passing scoundrel and pops out a baby 9 months later - you raise the child as yours, allowing your daughter to appear a bit more respectable and therefore marriageable. That sort of thing happens all the time, and always has.

It's usually done legally now, and there's a paper trail to prove it. But 400 years ago, among farm labourers in a rural community? Generally there is no record at all. So, John Smith is recorded as the son of William Smith, and that's all we know. Who was his biological father? Maybe William Smith, maybe someone else entirely.

Given human nature, over the course of just a few hundred years there is very little chance that anyone doesn't have a cuckoo or two in their family tree. Over the course of 2000 years, even if perfect records existed, there is zero chance that they're a true record of who begat who.
Reply With Quote
  #17  
Old 06-11-2010, 11:23 AM
Acsenray Acsenray is offline
Charter Member
 
Join Date: Apr 2002
Location: U.S.A.
Posts: 26,699
Quote:
Originally Posted by Colibri View Post
Actually, at this distance in time it's a virtual certainty that anyone with any European ancestry is descended from Caesar's family (though not Julius, as his children left no descendants). This is due to pedigree collapse - as you go back in time, more and more of your ancestors are shared with others (see Cecil's column here). By the time you go back 2000 years, or around 100 generations, you are descended from essentially everyone who was alive in Europe at the time who has living descendants.
Quote:
Originally Posted by John DiFool View Post
Isn't like 25% of all Central Asian peoples descended from Genghis Khan?
And some huge percentage of English people are descended from Edward III.
Reply With Quote
  #18  
Old 06-11-2010, 11:46 AM
sevenwood sevenwood is offline
Guest
 
Join Date: Aug 2003
Quote:
Originally Posted by Shakester View Post
It's not proven that Julius' bloodline died out. His legitimate bloodline died out, but there is absolutely no way of knowing whether or not he knocked up a senator's wife and/or some random British slave girl and through her has millions of living descendants.
My mother once informed me that I was descended from a long line that Julius Caesar once told...
Reply With Quote
  #19  
Old 06-11-2010, 11:53 AM
Little Nemo Little Nemo is online now
Charter Member
 
Join Date: Dec 1999
Location: Western New York
Posts: 58,490
Julius Caesar was a notorious womanizer and there were numerous rumors in his lifetime of his having illegitimate children. One of his assassins, Marcus Junius Brutus, was one of these rumored children.

But he only had two children he acknowledged; his daughter Julia Caesaris by his wife Cornelia Cinna and his son Caesarion by Cleopatra. He also adopted his grandnephew Octavian (Augustus) as a son.

Gotterfunken already explained what happed to Julia and Caesarion.

Augustus had one daughter, also named Julia. She had five children: Gaius, Julia, Lucius, Agrippina, and Agrippa. The only of these who lived to have children was Agrippina, who had nine children. Three died in infancy and the other six were Nero, Drusus, Gaius (Caligula), Agrippina, Drusilla, and Livilla. Nero, Drusus, Drusilla, and Livilla died childless. Caligula had a daughter Julia Drusilla who was killed along with her father. Agrippina had one son, Lucius (the future emperor Nero). Nero had a daughter Claudia who died in 63 AD. Nero died in 68 AD and was the last legitimate biological descendant of Augustus Ceasar. (I've left out various adopted and illegitimate children.)
Reply With Quote
  #20  
Old 06-11-2010, 12:07 PM
Sampiro Sampiro is offline
Guest
 
Join Date: Aug 2002
Quote:
Originally Posted by Little Nemo View Post
Julius Caesar was a notorious womanizer and there were numerous rumors in his lifetime of his having illegitimate children. One of his assassins, Marcus Junius Brutus, was one of these rumored children.

But he only had two children he acknowledged; his daughter Julia Caesaris by his wife Cornelia Cinna and his son Caesarion by Cleopatra. He also adopted his grandnephew Octavian (Augustus) as a son.
Brutus and his sisters had a good chance of being his son as their mother, Servilia, was widely known to be not just Caesar's mistress but the love of his life. He lavished gifts on her; at a time when the average salary of a Roman soldier was 500 denarii per year he gave her a black pearl necklace valued at 5,000,000 denarii. (Thank you All Roads Lead to Rome special feature on the HBO Rome DVD .)

Caesarion was allegedly his son but who knows. Contrary to the movies he never actually acknowledged him, and he almost certainly would have since not only was it a healthy male heir but one born to the richest and most powerful woman in the known world of the Romans. Also contrary to the movies it is unknown what became of Caesarion; it's assumed he was killed but there's no proof, he just vanished from the records.

Cleopatra would probably have descendants. In addition to Caesarion she had three children with Mark Antony: Alexander Helios (Sun), Cleopatra Selene (Moon), and Philadelphius who were taken to Rome and reared by Antony's wife (who also raised some of his other children, legitimate and ill-, in addition to her two daughters with him). Only Selene is known for certain to have had children, but she had two (King Ptolemy of Numidia and his sister Drusilla), but the records stop with them, though Queen Zenobia was alleged to be a descendant of Drusilla in her own lifetime.

Most genealogies are completely forgotten within surprisingly few generations though. I didn't know the names of several of my Civil War era ancestors until I began researching them and that's only four generations removed from me- for that matter it's only one person removed since I knew their grandchildren who knew them- and while I'm not royalty I do live in a society where the vast majority are literate and I even grew up near where these people lived. It's easy to see how the fact great-great-great-grandma was a queen or great-great-great-great-grandpa was the most famous man of his time can not get passed down when you don't have his money or power and you're illiterate and in a land where not many people care and frankly it can be dangerous to claim the ancestry.
The royal family of England has full time genealogists who devote their careers to researching the royal pedigree, and even they have a few dead ends (not of the crowned heads lines obviously, but of some of their spouses and branches). Even for the super well known records can be spotty: as much as has been written about Anne Boleyn, for example, we're not sure what her date or even year of birth is.

Last edited by Sampiro; 06-11-2010 at 12:09 PM..
Reply With Quote
  #21  
Old 06-11-2010, 12:45 PM
Chronos Chronos is offline
Charter Member
 
Join Date: Jan 2000
Location: The Land of Cleves
Posts: 54,813
Quote:
Isn't like 25% of all Central Asian peoples descended from Genghis Khan?
100% of Central Asian peoples, and in fact 100% of all humans in the world, are descended from Genghis Khan. Which is unremarkable, given that there are billions of swineherds and subsistence farmers who can make the same claim. What's remarkable about Genghis is that 8% of the population of that part of the world is descended from him in the purely male line. That is to say, if you start with anyone in central Asia, and look at their father, and then their father's father, and then his father, and so on, 8% of the time you'll end up with Genghis.
Reply With Quote
  #22  
Old 06-11-2010, 12:52 PM
chrisk chrisk is offline
Charter Member
 
Join Date: Nov 2003
Location: Southern ontario
Posts: 5,982
Quote:
Originally Posted by Chronos View Post
100% of Central Asian peoples, and in fact 100% of all humans in the world, are descended from Genghis Khan.
Can you cite for that?

I'd believe 'approaching 100%', but - aren't there regions that were until recently very isolated communities going back hundreds and hundreds of years, where you still might find a few people who didn't have an 'outsider' for an ancestor?
Reply With Quote
  #23  
Old 06-11-2010, 01:37 PM
robby robby is offline
Charter Member
 
Join Date: Dec 2000
Location: Connecticut, USA
Posts: 4,485
Quote:
Originally Posted by John DiFool View Post
Isn't like 25% of all Central Asian peoples descended from Genghis Khan?
Quote:
Originally Posted by Chronos View Post
100% of Central Asian peoples, and in fact 100% of all humans in the world, are descended from Genghis Khan. Which is unremarkable, given that there are billions of swineherds and subsistence farmers who can make the same claim. What's remarkable about Genghis is that 8% of the population of that part of the world is descended from him in the purely male line. That is to say, if you start with anyone in central Asia, and look at their father, and then their father's father, and then his father, and so on, 8% of the time you'll end up with Genghis.
No cite for Genghis Khan in particular, but if you go far enough back in time, it is a mathematical certainty that any person living at that moment in time is either an ancestor of everyone alive today, or has no living descendants--with no exceptions. A person who can count everyone alive today as one of his/her descendants is called a "common ancestor." The common ancestor who lived most recently is called the "most recent common ancestor" (MRCA)

What's surprising is how recent the MRCA lived. For all humans alive today, the MRCA likely lived sometime between the sixth millennium BC to the first or second millennium BC. (ETA: if these estimates are correct, it makes it unlikely that Genghis Khan is a common ancestor of all humans alive today. He may be a common ancestor of all Central Asian people, but probably not everyone on the planet.)

If you consider subgroups of all humans alive today, such as Western Europeans, the MRCA of all Western Europeans might have been alive as recently as 1000 AD.

If this estimate is correct, it is unsurprising that a huge percentage of English people were descended from Edward III. Indeed, it would not be surprising if all English people alive today (with English ancestry) are descended from Edward III.

Last edited by robby; 06-11-2010 at 01:40 PM..
Reply With Quote
  #24  
Old 08-14-2010, 01:36 PM
shane lee shane lee is offline
Guest
 
Join Date: Aug 2010
if i may ask from anyone here that can help me on some info,i cannot give away to much info due to mass criticism but i would like to speak to somome whos expertise in this matter is accompanied by extensive knowledge. i may have proof that the blood line does live on today.
Reply With Quote
  #25  
Old 08-14-2010, 01:53 PM
Quartz Quartz is offline
Charter Member
 
Join Date: Jan 2003
Location: Home of the haggis
Posts: 20,022
Quote:
Originally Posted by robby View Post
What's surprising is how recent the MRCA lived. For all humans alive today, the MRCA likely lived sometime between the sixth millennium BC to the first or second millennium BC.
I find that exceptionally difficult to believe. I'm aware of the maths, but it takes no account of geographic localisation. For example, the MRCA of a Zulu and an Australian Aborigine is going to predate humanity's expansion from Africa, 75000-odd years ago. Similarly, the MRCA of a Basque and an Inca is going to be at least 10000 years ago.
Reply With Quote
  #26  
Old 08-14-2010, 02:01 PM
Colibri Colibri is offline
SD Curator of Critters
Moderator
 
Join Date: Oct 2000
Location: Panama
Posts: 25,757
Quote:
Originally Posted by Quartz View Post
Quote:
Originally Posted by robby View Post
What's surprising is how recent the MRCA lived. For all humans alive today, the MRCA likely lived sometime between the sixth millennium BC to the first or second millennium BC.
I find that exceptionally difficult to believe. I'm aware of the maths, but it takes no account of geographic localisation. For example, the MRCA of a Zulu and an Australian Aborigine is going to predate humanity's expansion from Africa, 75000-odd years ago. Similarly, the MRCA of a Basque and an Inca is going to be at least 10000 years ago.
You are imaging that these people's lineages have remained isolated since the time of the most recent common ancestor, which of course is not the case. Anyone alive today has potentially over one million ancestors alive just 500 years ago, and the numbers become astronomical beyond a few thousand years ago. It's very likely that any descendant of an Inca today also has a conquistador and an African slave somewhere in their pedigree, even if they are very close to being pure Indian. And that European had some ancestors who were Basques and Mongols, and the African had some ancestors within the past few millenia who were Khoisan, Zulu, or Pygmies.
Reply With Quote
  #27  
Old 08-14-2010, 03:42 PM
Quartz Quartz is offline
Charter Member
 
Join Date: Jan 2003
Location: Home of the haggis
Posts: 20,022
Quote:
Originally Posted by Colibri View Post
Quote:
Originally Posted by Quartz View Post

I find that exceptionally difficult to believe. I'm aware of the maths, but it takes no account of geographic localisation. For example, the MRCA of a Zulu and an Australian Aborigine is going to predate humanity's expansion from Africa, 75000-odd years ago. Similarly, the MRCA of a Basque and an Inca is going to be at least 10000 years ago.
You are imaging that these people's lineages have remained isolated since the time of the most recent common ancestor, which of course is not the case.
Actually, with the examples I've chosen, it's very likely the case. If you're fussy, assume purity of line since 1500 AD.
Reply With Quote
  #28  
Old 08-14-2010, 03:48 PM
Colibri Colibri is offline
SD Curator of Critters
Moderator
 
Join Date: Oct 2000
Location: Panama
Posts: 25,757
Quote:
Originally Posted by Quartz View Post
Actually, with the examples I've chosen, it's very likely the case.
No, it's not.

Quote:
If you're fussy, assume purity of line since 1500 AD.
That assumption is not compatible with the actual historical situation.
Reply With Quote
  #29  
Old 08-14-2010, 04:48 PM
Quartz Quartz is offline
Charter Member
 
Join Date: Jan 2003
Location: Home of the haggis
Posts: 20,022
If you insist, take a tribesman from the deep Amazon and an Andamanian - you know, those ones who shoot at helicopters - at least 10000 years of isolation. Or a Bushman from the Kalahari and an Australian Aborigine: longer than since humanity expanded from Africa
Reply With Quote
  #30  
Old 08-14-2010, 04:55 PM
Huerta88 Huerta88 is offline
Guest
 
Join Date: Sep 2002
http://www.theonion.com/articles/7-m...gle-smoo,2762/

It was a plot point in a novel that I read recently that the House of Saud claim to be (literally) the lineal heirs to Muhammad.

(a) Is this factually true (i.e., that they make this claim as a basis for their legitimacy)?

(b) If they do make the claim, how good/bad is their theoretical succession of begats?
Reply With Quote
  #31  
Old 08-14-2010, 05:09 PM
Colibri Colibri is offline
SD Curator of Critters
Moderator
 
Join Date: Oct 2000
Location: Panama
Posts: 25,757
Quote:
Originally Posted by Quartz View Post
If you insist, take a tribesman from the deep Amazon and an Andamanian - you know, those ones who shoot at helicopters - at least 10000 years of isolation. Or a Bushman from the Kalahari and an Australian Aborigine: longer than since humanity expanded from Africa
You're still not getting it. These populations are not isolated in the way they would have to be for there not to be a recent MRCA. In the last 500 years, a tribe even deep in the Amazon has not remained isolated from breeding with the tribe next to it, nor that tribe with the tribe next to it, and so on. At some point in the past one of those tribes has a member who is descended from a European colonist or an African slave, and who was ancestral to one of the tribespeople who married into the most isolated tribe. Even with the Andamanese, it's a near certainty the pedigree of the group includes one or more Arab or Tamil or Malay or Portuguese seafarers. The Andamese as a group may have originated tens of thousands of years ago; but if there has been any interbreeding at all they will share a more recent common ancestor with other populations.

Once you get back a few dozen generations, the number of potential ancestors is so astronomical that even rare interbreeding events will be found in the pedigrees of everyone.

Last edited by Colibri; 08-14-2010 at 05:10 PM..
Reply With Quote
  #32  
Old 08-14-2010, 05:10 PM
Lemur866 Lemur866 is offline
Charter Member
 
Join Date: Jul 2000
Location: The Middle of Puget Sound
Posts: 16,878
Quote:
Originally Posted by Quartz View Post
If you insist, take a tribesman from the deep Amazon and an Andamanian - you know, those ones who shoot at helicopters - at least 10000 years of isolation. Or a Bushman from the Kalahari and an Australian Aborigine: longer than since humanity expanded from Africa
So on that island, not a single person from the mainland has arrived in 10,000 years? They killed every single one, for 10,000 years? And tribes in the Amazon aren't isolated, they trade with each other, people move. We have plenty of evidence of Australian trade with Indonesians prior to European contact. And given the history of European settlement, how many Australian aborigines do you think have zero European ancestors? And Kalahari bushmen are in regular contact with their neighbors, it is impossible that there hasn't been a non-bushman in their ancestry for 10,000 years.
Reply With Quote
  #33  
Old 08-14-2010, 05:18 PM
Wendell Wagner Wendell Wagner is offline
Charter Member
 
Join Date: Jul 1999
Location: Greenbelt, Maryland
Posts: 11,836
Article about Genghis Khan's bloodline:

http://news.nationalgeographic.com/n...4_genghis.html
Reply With Quote
  #34  
Old 08-14-2010, 05:23 PM
MonkeyMensch MonkeyMensch is offline
Charter Member
 
Join Date: Jul 2001
Location: Encinitas
Posts: 2,160
Quote:
Originally Posted by Chronos View Post
Quote:
Isn't like 25% of all Central Asian peoples descended from Genghis Khan?
100% of Central Asian peoples, and in fact 100% of all humans in the world, are descended from Genghis Khan. Which is unremarkable, given that there are billions of swineherds and subsistence farmers who can make the same claim. What's remarkable about Genghis is that 8% of the population of that part of the world is descended from him in the purely male line. That is to say, if you start with anyone in central Asia, and look at their father, and then their father's father, and then his father, and so on, 8% of the time you'll end up with Genghis.
Which is why I, with Eastern Polish blood in me, claimed Mongol as part of my ethnicity when asked on the most recent US Census.
Reply With Quote
  #35  
Old 08-14-2010, 05:59 PM
Rusalka Rusalka is offline
Charter Member
 
Join Date: Jul 2000
Posts: 972
Quote:
Originally Posted by Colibri View Post
Quote:
Originally Posted by Quartz View Post
If you insist, take a tribesman from the deep Amazon and an Andamanian - you know, those ones who shoot at helicopters - at least 10000 years of isolation. Or a Bushman from the Kalahari and an Australian Aborigine: longer than since humanity expanded from Africa
In the last 500 years, a tribe even deep in the Amazon has not remained isolated from breeding with the tribe next to it, nor that tribe with the tribe next to it, and so on. At some point in the past one of those tribes has a member who is descended from a European colonist or an African slave, and who was ancestral to one of the tribespeople who married into the most isolated tribe. Even with the Andamanese, it's a near certainty the pedigree of the group includes one or more Arab or Tamil or Malay or Portuguese seafarers.
There are a lot of "ifs" in there. You are assuming that every indigenous group on earth has interbred with Europeans, etc., and that is a big assumption. Where do you get your data? There are many tribes who have indeed remained isolated from outside contact. How can you say it's a "near certainty" that every member of an isolated group is related to outsiders?

Last edited by Rusalka; 08-14-2010 at 06:01 PM..
Reply With Quote
  #36  
Old 08-14-2010, 06:05 PM
John Mace John Mace is offline
Guest
 
Join Date: Dec 2002
Quote:
Originally Posted by Rusalka View Post
Quote:
Originally Posted by Colibri View Post

In the last 500 years, a tribe even deep in the Amazon has not remained isolated from breeding with the tribe next to it, nor that tribe with the tribe next to it, and so on. At some point in the past one of those tribes has a member who is descended from a European colonist or an African slave, and who was ancestral to one of the tribespeople who married into the most isolated tribe. Even with the Andamanese, it's a near certainty the pedigree of the group includes one or more Arab or Tamil or Malay or Portuguese seafarers.
There are a lot of "ifs" in there. You are assuming that every indigenous group on earth has interbred with Europeans, etc., and that is a big assumption. Where do you get your data? There are many tribes who have indeed remained isolated from outside contact. How can you say it's a "near certainty" that every member of an isolated group is related to outsiders?
It's not difficult to believe that gene flow between European explorers entered deep into Amazonia over the centuries just as Colibri explained-- by neighbors breeding with neighbors.

The tricky part is getting to the point where everyone in that "remote village" is a descendant of someone who bred with the neighbors, who bred with the neighbors, who... bred with a European (or Asian or whatever).

The studies Colibri is referring to are based on probabilistic models and/or simulations. 500 years is a long time for genes to flow around the world. Had we been talking about this 300 years ago, things would probably be different.

Last edited by John Mace; 08-14-2010 at 06:06 PM..
Reply With Quote
  #37  
Old 08-14-2010, 06:22 PM
Colibri Colibri is offline
SD Curator of Critters
Moderator
 
Join Date: Oct 2000
Location: Panama
Posts: 25,757
Quote:
Originally Posted by Rusalka View Post
There are a lot of "ifs" in there. You are assuming that every indigenous group on earth has interbred with Europeans, etc., and that is a big assumption. Where do you get your data? There are many tribes who have indeed remained isolated from outside contact. How can you say it's a "near certainty" that every member of an isolated group is related to outsiders?
You're also not getting it. There is no tribe on Earth that is completely isolated from all other groups, and has been so for thousands of years. As I already pointed out, it is not necessary for the tribe itself to have ever directly interbred with Europeans. It is only necessary for them to have interbred with adjacent groups that have; or with groups adjacent to other groups that have. And Europeans and Africans have been all over Amazonia for hundreds of years.

Also, I am not assuming that every indigenous group on Earth has interbred with Europeans. In fact, it's far more likely that the most recent common ancestor was a Central Asian. Mongols and even earlier nomadic groups made incursions into Europe, the Middle East, and South Asia. Through these contacts, they would have interbred not only with Europeans, but with groups like the Arabs, who penetrated much of Africa, and Indonesian peoples who had contact with Australia.

I'm of Irish and German ancestry. If you take it back a couple of millenia, I certainly have several ancestors who were African slaves who had been brought to Rome, and Huns who had originally come from Central Asia. Any Europeans who colonized the Americas and Australia also would have had similar ancestry 20 generations back.

Last edited by Colibri; 08-14-2010 at 06:24 PM..
Reply With Quote
  #38  
Old 08-14-2010, 06:26 PM
Colibri Colibri is offline
SD Curator of Critters
Moderator
 
Join Date: Oct 2000
Location: Panama
Posts: 25,757
Quote:
Originally Posted by John Mace View Post
The tricky part is getting to the point where everyone in that "remote village" is a descendant of someone who bred with the neighbors, who bred with the neighbors, who... bred with a European (or Asian or whatever).
If the tribe is small, it doesn't take much time on the scale that we are talking about; maybe five or six generations.
Reply With Quote
  #39  
Old 08-14-2010, 06:34 PM
Sage Rat Sage Rat is online now
Member
 
Join Date: Mar 2004
Location: Howdy
Posts: 14,614
Quote:
Originally Posted by YamatoTwinkie View Post
If you figure about 30 years between generations, and two kids per generation, then there are about 2^(2100/30) = ~a sextillion descendents of Julius Caesar (or if not Caesar himself, then Caesar's cousin) alive today. Obviously, his family tree had some straight sections to it because that's more than the population of the planet, but still, the point remains, if you have *any* European blood, your chances are pretty good at being one of those descendents.
Technically, you are many of his descendants, which is why there aren't a sextillion people.
Reply With Quote
  #40  
Old 08-14-2010, 07:06 PM
Candyman74 Candyman74 is offline
Registered User
 
Join Date: Sep 2008
Quote:
Originally Posted by John DiFool View Post
Isn't like 25% of all Central Asian peoples descended from Genghis Khan?
I never understand these statistics. In that case, surely there were only 4 people alive at the time? Or did he procreate with 25% of the women available at the time?

What happened to the other hundreds of thousands of people alive in Central Asia at the time who therefore only - between them all - accounted for 75% of the descendants? How did he manage to corner a whole quarter of the population? Surely 99.9999% of the women at the time didn't procreate with Genghis Khan, and they have decendants too, no? Which multiplied at the same rate as his descendants?

How does that make 25% of people thousands of years later descended from him? Surely 99.999% of people are descended from people who lived at the same time but who never even met him, let alone procreated with him?

As is clear, I do not have a grasp on how this works!

Last edited by Candyman74; 08-14-2010 at 07:07 PM..
Reply With Quote
  #41  
Old 08-14-2010, 09:53 PM
Acsenray Acsenray is offline
Charter Member
 
Join Date: Apr 2002
Location: U.S.A.
Posts: 26,699
He doesn't have to "corner" a huge proportion of the population in order to be an ancestor ro 100 percent of the population.

As has been pointed out, once you go back a few generations, your ancestry is no longer filled out by unique individuals.

The 25 percent figure is the proportion of Central Asian men who are direct male-line descendants of Genghis Khan.

As an aside, I've read that Genghis Khan fathered children on about 1,000 different women.
Reply With Quote
  #42  
Old 08-15-2010, 03:17 AM
septimus septimus is online now
Guest
 
Join Date: Dec 2009
Quote:
Originally Posted by acsenray View Post
Quote:
Originally Posted by John DiFool View Post
Isn't like 25% of all Central Asian peoples descended from Genghis Khan?
And some huge percentage of English people are descended from Edward III.
5% of males within the old Mongol Empire have been shown to have nearly identical Y-chromosomes -- it's only a (very good) assumption that this is the chromosome of Temudzin "Greatest of Rulers". With this huge agnatic descent, Temudzin must be ancestral in some way to 99% of Central Asians, any exceptions being recent immigrants.

Edward III is not a similar story. While simple math might suggest he has many millions of living descendants, class barriers may make the actual number much smaller. Certainly most American genealogists are unable to find their own proven line of descent from Edward III.

Reasons for the greater procreative success of the Mongol Khans are well known:
SPOILER:
Five hundred wives and concubines composed the harem of Genghis
...
Kublai Khan's underling, the celebrated Italian traveler Marco Polo, wrote that each year the emperor took 30 additional virgins to be his concubines from a province renowned for the beauty of its women.


Quote:
Originally Posted by Shakester View Post
There isn't anyone who can realistically trace their ancestry back 2000 years. Reliable records - even in the most aristocratic families - don't exist before the renaissance.
This may be applicable to Europe's "Dark Ages" but isn't universal. Many Chinese allege "proven" descent from Confucius, who lived 2500 years ago. Aristocrats of ancient Persia, Greece and Rome kept records; the problem is extending those genealogies to the present. It might be doable if a single blood-line prevailed as rulers throughout such a long period; Ireland's O'Neil family may come close but I don't think historians extend it much before Niall Noigiallach (born 4th century).

Quote:
Originally Posted by Huerta88 View Post
It was a plot point in a novel that I read recently that the House of Saud claim to be (literally) the lineal heirs to Muhammad.
The Saud claim is, AFAIK, just fiction. The King of Jordan, on the other hand, shows on his own website a detailed agnatic lineage back to Ali ibn Abu Talib (who married the daughter of the Prophet). I don't think that line has been de-bunked (but doubt it's been bunked either).

For long lines, a question that arises is how thoroughly must each link be known to be valid? If some ancient's mother was "almost certainly" a Frankish Princess can that be counted as a link, despite that details are unknown?

For example, Alfred the Great's grandmother Redburga was described contemporaneously as "regis Francorum sororia", but no details are confirmed. Yet all reconstructions make her a g-g granddaugher of Charles Martel. Would you accept that all descendants of Alfred are therefore proven descendants of Charles Martel?
Reply With Quote
  #43  
Old 08-15-2010, 08:44 AM
Wendell Wagner Wendell Wagner is offline
Charter Member
 
Join Date: Jul 1999
Location: Greenbelt, Maryland
Posts: 11,836
septimus writes:

> 5% of males within the old Mongol Empire have been shown to have nearly
> identical Y-chromosomes

8%, as is indicated in the link in my post (#33).
Reply With Quote
  #44  
Old 08-15-2010, 09:52 AM
Acsenray Acsenray is offline
Charter Member
 
Join Date: Apr 2002
Location: U.S.A.
Posts: 26,699
Quote:
Originally Posted by Candyman74 View Post
I never understand these statistics. In that case, surely there were only 4 people alive at the time? Or did he procreate with 25% of the women available at the time?

What happened to the other hundreds of thousands of people alive in Central Asia at the time who therefore only - between them all - accounted for 75% of the descendants? How did he manage to corner a whole quarter of the population? Surely 99.9999% of the women at the time didn't procreate with Genghis Khan, and they have decendants too, no? Which multiplied at the same rate as his descendants?

How does that make 25% of people thousands of years later descended from him? Surely 99.999% of people are descended from people who lived at the same time but who never even met him, let alone procreated with him?

As is clear, I do not have a grasp on how this works!
1. A lot of Chinghiz Khan's contemporaries will have "failed" lines with no living descendants.

2. Those with successful lines will, through intermarriage with succeeding generations, become related, eventually, become ancestors to all living people.

3. Think about your family tree. At done point the power of 2 associated with the number if generations back becomes larger than the number of people who actually lived at that time.
Reply With Quote
  #45  
Old 08-15-2010, 12:04 PM
Captain Midnight Captain Midnight is offline
BANNED
 
Join Date: Jun 2010
Posts: 409
What about Sid Caesar?
Reply With Quote
  #46  
Old 08-15-2010, 01:12 PM
Chronos Chronos is offline
Charter Member
 
Join Date: Jan 2000
Location: The Land of Cleves
Posts: 54,813
Quote:
2. Those with successful lines will, through intermarriage with succeeding generations, become related, eventually, become ancestors to all living people.

3. Think about your family tree. At done point the power of 2 associated with the number if generations back becomes larger than the number of people who actually lived at that time.
Neither of these arguments is applicable to the all-male line, like we have with Genghis. When you're talking about an all-male line, it's 1 to a very large power, not 2 to that power.

The fact that Genghis himself had children by so many women is a good start, but for it to really work out, you also need for his sons, and their sons, to also be well above-average in fruitfulness. It might be that Genghis just had really good genes and so his sons also tended to be very fit (where "fit" can be any trait that makes them more likely to score), or it might be that there was some social or monetary benefit to being a son of the Great Emperor that propelled them into advantageous positions.
Reply With Quote
  #47  
Old 08-15-2010, 01:24 PM
Dr. Drake Dr. Drake is offline
Guest
 
Join Date: Jan 2006
Quote:
Originally Posted by Chronos View Post
When you're talking about an all-male line, it's 1 to a very large power, not 2 to that power.
Surely it's 2(a very large power-1)? (That is, 2 to a very large power, but divided in half.) 1 is still one.
Reply With Quote
  #48  
Old 08-15-2010, 01:46 PM
septimus septimus is online now
Guest
 
Join Date: Dec 2009
Quote:
Originally Posted by Chronos View Post
The fact that Genghis himself had children by so many women is a good start, but for it to really work out, you also need for his sons, and their sons, to also be well above-average in fruitfulness.
The Khans practiced rape and had vast harems for many generations. I can't Google it, but one visitor to a Khan (other than Genghis or Kublai?) reported the Khan proudly showing him over 1000 of his children.

Still the "Genghis Khan Y-chromosome" seems statistically amazing! I don't think researchers can rule out that other Mongol warlords contemporaneous to Genghis were his agnatic cousins and that this Y-chromosome had already benefited from a century or more of rape.

(Deductions about prehistory from Y-dna is a fascinating area. The presence of Q-haplogroup in Scandinavia is an interesting enigma about which it might be fun to start a thread.)
Reply With Quote
  #49  
Old 08-15-2010, 01:50 PM
Dr. Drake Dr. Drake is offline
Guest
 
Join Date: Jan 2006
Quote:
Originally Posted by Dr. Drake View Post
Quote:
Originally Posted by Chronos View Post
When you're talking about an all-male line, it's 1 to a very large power, not 2 to that power.
Surely it's 2(a very large power-1)? (That is, 2 to a very large power, but divided in half.) 1 is still one.
Never mind: I see what you meant now.
Reply With Quote
  #50  
Old 08-15-2010, 01:56 PM
Colibri Colibri is offline
SD Curator of Critters
Moderator
 
Join Date: Oct 2000
Location: Panama
Posts: 25,757
Quote:
Originally Posted by Chronos View Post
The fact that Genghis himself had children by so many women is a good start, but for it to really work out, you also need for his sons, and their sons, to also be well above-average in fruitfulness.
Genghis was succeeded by his sons and grandsons, including Kublai Khan. I am not sure how long his direct male line continued in power, but since they would have had large harems they certainly would have had ample opportunity to spread their genes around. I'm not sure how successful other male descendants were, but I doubt being related to the Great Khan was a disadvantage.
Reply With Quote
Reply



Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 12:49 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.

Send questions for Cecil Adams to: cecil@chicagoreader.com

Send comments about this website to: webmaster@straightdope.com

Terms of Use / Privacy Policy

Advertise on the Straight Dope!
(Your direct line to thousands of the smartest, hippest people on the planet, plus a few total dipsticks.)

Publishers - interested in subscribing to the Straight Dope?
Write to: sdsubscriptions@chicagoreader.com.

Copyright © 2013 Sun-Times Media, LLC.