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How many total ancestors do you have?

Genealogists identify ancestors by following paper trails preserved in archives—traditional and digital. Although the goals of genealogists vary, a large pedigree chart is one measure of success. Yet even the most fruitful family trees are unlikely to yield more than a few thousand ancestors. One royal genealogy database shows only ~42,000 for the Queen of Canada herself. Yet, as the mathematically-inclined will be quick to point out, one can never find the names of more than a tiny fraction.

So, is an answer possible? I think the beginning of an answer is possible, within certain limits. This is a question for what might be called theoretical genealogy. Like any question of this magnitude, no matter what the discipline, it requires some agreement on definitions. An ancestor is someone who could theoretically been the source of some of your DNA. I say "theoretically," because most of your ancestors could not actually have passed DNA on to you. The probability is too low, since your number of ancestors greatly exceeds your number of genes. So we are counting parents, plus grandparents, plus great-grandparents, etc., until we reach an arbitrary beginning. 10,000 BCE should do nicely, as it puts us at the very beginning of the Anthropocene, the planet's first geologic era caused by us.

My video is an attempt to answer the question, using a theoretical model, some speculation, and a little calculus. A full DK version of the answer, for those who would rather read and engage here, is below the Orange Squiggle of Wonder, and see how closely we are all connected—to each other and to billions of shared ancestors. It's based on the video script, but different because the format is different.

The answer seems easy at first. Your two parents each have two parents, making four grandparents, eight great-grandparents, sixteen great-great-grandparents, thirty-two great-great-great-grandparents... Just keep doubling and adding right? Not for long. While your 10th generation could just have 1,024 unique ancestors, bringing your total to 2,046, it probably doesn't. I've never come across anyone who had this complete of a pedigree, all with unique ancestors.

In any case, doubling is guaranteed to fail. While everyone's ancestral lines increase in this way, many of the slots are filled by repeats.

Here's why this is inevitable. Even if we had no living examples and no records, the existence of cousin marriage could be proved by math alone.

28-year generations mean that we should expect our average 31st generation ancestors to have been born around the year 1117, when the population of Earth was less than 600 million. But the 31st generation requires more than 2 billion ancestral lines.

Scholars who lived in the 12th century were fascinated by impossible doublings like these. In one legend, an Indian king is so impressed by the game of chess that he offers its inventor a reward of his choosing. The inventor's request--€”1 grain of wheat on the first square of the chessboard, 2 on the second, 4 on the third, the doubling continuing until the 64th square--€”amounts to more than 10 to the 19th grains. The king could never have paid this amount, over 9 times the value of the global economy in 2014, or enough grains of wheat to completely fill Lake Superior. That same number is your number of ancestral lines in the 64th generation, less than 2,000 years ago. If they were all unique individuals, they couldn't fit on the surface of Earth, plus 12 Jupiters.

So, we need to refine the question. How many unique ancestors do you have? For this we need a real world example, and for counting ancestors the most complete family trees available are those of European royalty. The ancestors of the current queen of Denmark double for a few generations, but in the 5th generation, she has 28 instead of the expected 32. Because her parents were double 3rd cousins, these ancestors (and all of their ancestors) repeat. Continued cousin marriage makes her ancestry look more like a family spinning top than a family tree. Instead of over a million 20th generation ancestors, she has only about 6,000, mostly of the tiny ruling class of Renaissance Europe—16 millionths of the world population.

It's well known that European royals often married close cousins, although they've mostly stopped. While the Queen and Duke of Edinburgh are second cousins (and related in countless other ways), the closest relation of the Duke and Duchess of Cambridge is 12th cousin once removed, and European royals are even starting to marry non-Europeans like the Queen of the Netherlands, from Argentina, and Princess Angela of Liechtenstein, who is Afro-Panamanian, and thus probably even more distantly related to her husband.

But your ancestors married close cousins too, guaranteed. One anthropologist, Robin Fox, has estimated that the average marriage has been between second cousins and closer. In any case, the cause of children is sex, not marriage, and real genealogies are real life. On the more tragic end of this spectrum, children, just as today, were born of rape within families. Some of them are your ancestors too.

Small populations mean that nearly every possible mate is closer than a 4th cousin. Your ancestors grow much like the queen's if they lived in small villages or isolated islands, or if they maintained traditions that encouraged close cousin marriage, such as tribal, religious, or caste endogamy.

Ethnic diversity and other forms of exogamy in your background will tend to make your number of 20th generation ancestors higher than the queen's 3,000. People with geographically diverse ancestry have more small in-marrying groups in their ancestry. At the other extreme are groups like the Sentinelese, who some believe are the most isolated community in the world. If they have truly remained uncontacted, and have rejected migrants to their Andaman Sea island for centuries, their number of 20th generation ancestors could be just a few hundred. Sustained first cousin marriage could make someone's number even less... as low as 6. 6 great-great-grandparents, 6 great-great-great-grandparents, etc.

We know that your number of ancestors at any given point is less than the world population. Some people never become ancestors. Others have lines that go extinct. However, our number of ancestors does approach the world population, and in historical time. If we assume that the queen's ancestors continue to accumulate at about the same rate, they converge toward the total population of Earth about 150 generations ago in the third millennium BC.

This fits well with one model of the timing of the identical ancestors point--€”the point in time before which every living human today shares the same set of ancestors. Anyone who was alive at or before this identical ancestors point either became the ancestor of everyone living today or the ancestor of no one living today. In a series of papers, Chang, Rohde, and Olson have run an increasingly complex series of simulations of human population history that attempt to calculate the date of this point. Their most recent paper identifies a mean identical ancestry date of 2158 BC, assuming relatively high migration. This is especially relevant for Eurasia and Africa, core regions of humanity that have been connected by trade and migration routes for thousands of years. A recent identical ancestors point for these regions of the world is starting to become supported by genetic data. In 2013, Ralph and Coop studied long genomic segments in Europeans' DNA that reflect these shared ancestors. Their distribution shows that ancestry can spread very quickly, with "individuals from opposite ends of Europe... expected to share millions of common genealogical ancestors over the last 1,000 years." The same applies to densely populated parts of Asia, which have held the majority of humanity for all of recorded history.
If we integrate the area under the curve we get by following this model, we get the number of years that our ancestors lived over the past 150 generations. Dividing by a life expectancy of 40 gives the figure of about 400 million ancestors since the 22nd century BC. By the same logic, there are another 1.5 billion people from the 150th generation to the 250th generation--Chang, Rohde, and Olson's more conservative IAP--then 4 billion more people back to 10,000 BC.

Using this model, a first estimate, the queen has about 6 billion ancestors since the domestication of wheat, a bit less than the current population of Earth, plus billions more in the Paleolithic past. a more complete answer than this requires a definition for the beginning of humanity or a decision to count pre-human ancestors, not only Neanderthals and Denisovans, but the ancestors that we share with chimpanzees, bonobos, all the other primates, all the other euarchontoglires, all the other mammals, all the other eukaryotes, etc. changing our numbers radically. So for this answer, let's stick to the relatively recent human past.

So, you have 6 billion ancestors in the past 12,000 years, plus or minus a few billion. Ancestry in endogamous groups will reduce this number, but not so low that you never catch up. You still have billions of Paleolithic ancestors you share with everyone. Indigenous peoples of the Americas and Australia, as well as smaller islands, might have the lowest, and people with diverse ancestry from various parts of Afroeurasia and the Americas, and long traditions of exogamy, will have the most ancestors. A lot of people in the United States, particularly African Americans and white Americans who have ancestry going back a few hundred years in North America will have the most, because of having ancestry from so many places. Just as a very, very rough estimate, I'd say that the range since 10,000 BCE is between 3 billion and 15 billion. A better mathematician should work on this.  

We do not all share the exact same number of ancestors, but it is clear that we all share the majority. 5,000 years ago, you could find your ancestors in any village on the planet. Today, their descendants, your cousins, are everyone you know.

Originally posted to Ruby JM on Tue Aug 12, 2014 at 05:34 PM PDT.

Also republished by Genealogy and Family History Community, White Privilege Working Group, and Community Spotlight.

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Comment Preferences

  •  Tip Jar (177+ / 0-)
    Recommended by:
    Bob Love, Shockwave, rasbobbo, pat of butter in a sea of grits, Shahryar, kerflooey, DEMonrat ankle biter, falconer520, rodentrancher, Els, jqjacobs, Villabolo, dwellscho, deben, lcrp, Chaddiwicker, housesella, riverlover, greenbird, rduran, AaronInSanDiego, houyhnhnm, ypochris, hayden, Gottlieb, Joy of Fishes, Freakinout daily, Meteor Blades, Wee Mama, Dvalkure, edwardssl, MPociask, Aunt Pat, 207wickedgood, annecros, eyesoars, 88kathy, worldlotus, SuWho, annominous, paradox, pixxer, LillithMc, MT Spaces, NonnyO, klompendanser, Redfire, GreyHawk, Emerson, JoanMar, NYFM, peachcreek, sawgrass727, DeadHead, schumann, craigkg, deepeco, basquebob, Heart of the Rockies, Unknown Quantity, pashber, JDWolverton, rsmpdx, Liberal Thinking, kaliope, Cassandra Waites, jeremybloom, ask, kurt, freshwater dan, Missys Brother, StrayCat, tardis10, DuzT, jcrit, laurak, rapala, RLF, BYw, FarWestGirl, Stwriley, richardvjohnson, Audri, leeleedee, jainm, Linda Wood, oslyn7, Sara R, eztempo, RiveroftheWest, triplepoint, purplepenlady, Denise Oliver Velez, TheDuckManCometh, Pinto Pony, Temmoku, BPARTR, kharma, rmabelis, Morningglory, middleagedhousewife, Windowpane, fenway49, Anthony Page aka SecondComing, askyron, JayC, terranova108, spiderh, livingthedream, Carol in San Antonio, Ahianne, 2thanks, politik, whaddaya, commonmass, zitherhamster, DawnN, unclejohn, VPofKarma, sturunner, pico, GrumpyOldGeek, kitchieboy, CWinebrinner, Andrew F Cockburn, SpotTheCat, cailloux, moiv, bartcopfan, JJG Miami Shores, nellgwen, fcvaguy, dconrad, kurious, Rogneid, Reginaldd, CelticOm, TellerCountyBlue, howabout, Skippah, wildweasels, greenotron, JuliathePoet, dasher3, penelope pnortney, dewolf99, Coaster Freak, scott on the rock, SirReal, rat racer, NotYerX, Helpless, Oh Mary Oh, Pariah Dog, petral, Munchkn, leftist vegetarian patriot, rhutcheson, mkfarkus, ChuckInReno, Jay C, Blissing, bobcat41702, diggerspop, Wes Kobernick, Catesby, Heart n Mind, Eowyn9, noladerf, rl en france, Escaped, yellowdogsal, Bob Duck, TooFolkGR, ItsaMathJoke, BvueDem, dalef77
  •  7,046,000,000, as of two years ago. n/t (11+ / 0-)

    "Those who can make you believe absurdities can make you commit atrocities." - Voltaire

    by Greyhound on Tue Aug 12, 2014 at 05:42:00 PM PDT

  •  Really interesting diary (29+ / 0-)


    I wonder how far back on average you have to go to find a common ancestor with someone whose ancestors lived in the same part of the world.

    •  she's on my list (5+ / 0-)
      Recommended by:
      Aunt Pat, NYFM, FarWestGirl, Rogneid, KLM

      f people I prefer not to acknowledge as a relative. Along with a bunch of other politicians.

      (Is it time for the pitchforks and torches yet?)

      by PJEvans on Tue Aug 12, 2014 at 06:41:55 PM PDT

      [ Parent ]

      •  How 'bout W? (0+ / 0-)

        I was shocked and distraught last week to see one of my New England ancestors is also - supposedly - an ancestor of Georgie Boy.

        Thankfully I'm in a different line. I'm descended from one son and GWB is descended from another... or something like that. Truthfully I didn't want to look too closely.

        Meddle not in the affairs of dragons... for thou art crunchy and good with ketchup.

        by Pariah Dog on Thu Aug 14, 2014 at 08:48:38 AM PDT

        [ Parent ]

    •  Not all the branches on a tree (8+ / 0-)

      grow straight and true .
      Some need to be pruned .  

      "please love deeply...openly and genuinely." A. M. H.

      by indycam on Tue Aug 12, 2014 at 08:28:52 PM PDT

      [ Parent ]

    •  If you were in a bar and really drunk she would be (10+ / 0-)

      funny. But only for that one time, and only in that one bar.

      Use REDUNDANT safety when hauling precious cargo-- Use open source E-Z Baby Saver -- Andrew Pelham, 11yo inventor E-Z Baby Saver

      by 88kathy on Tue Aug 12, 2014 at 08:37:18 PM PDT

      [ Parent ]

    •  I'm a ninth cousin. You don't choose your parents. (7+ / 0-)

      More accurately, ninth cousin once removed.

      It's a conversational ice-breaker. I get lots of sympathy. It's no more than that.

      Her Histrionic Personality Disorder is nurture, not nature. It'd be a different issue if you were closely related genetically and she had two heads and four boobs.

      Besides, in my case there are 21 steps (marriages) between us in the blood line and this dilutes the gene pool to less than 0.00005%.

      Lucille Desiree Ball is my eighth cousin twice removed.
      Wow! That's very cool.

      Sir Isaac Newton is my second cousin 9 times removed.
      Wow! You must be....

      It's fun, but means nothing.

      Ron Reagan, the son, vs. Saint Ronnie.
      Willie Hitler vs. his crazy Uncle Adolph.

      Charlemagne is my 41st great grandfather. Really.

      Also, too, you, so there.

      "Never wrestle with a pig: you get dirty and the pig enjoys it"

      by GrumpyOldGeek on Wed Aug 13, 2014 at 03:13:04 PM PDT

      [ Parent ]

      •  Well, hello cousin! (3+ / 0-)

        I'm a Charlemagne descendant, and my grandmother swore we were related to Lucille Ball. Recently, I came across some Balls in my family tree, so who knows? That might be another common branch.

        “Judge: Are you trying to show contempt for this court? Mae West: I was doin' my best to hide it.” ― Mae West

        by Rogneid on Wed Aug 13, 2014 at 04:37:03 PM PDT

        [ Parent ]

        •  Lucy's immediate family resided in NY for a time. (5+ / 0-)

          Your grandmother's story deserves to be checked out. Odds got better when you came across that name in your tree. (Why didn't I just write "Balls in your tree"?)

          Lucy's was born in Jamestown, Chautauqua, New York. Her maternal side settled in the area earlier than her Ball paternal line. The Ball paternal line wandered, but my connection originates in central MA where one of a series of Isaac Balls married Rachel Howe and that links to our common ancestors, John Howe and Mary Jones. It's devilishly tricky to find such blood-related connections.

          Lucy's Ball paternal line:
          Henry Durrell Ball b. Chautauqua Co., NY, d. In MI.
          Jasper Clinton Ball b. Vanango Co. PA, d. Erie Co NY
          Clinton Manross Ball b. Montpelier, VT, d. Chautauqua Co., NY
          Isaac Ball, b. Wilmington, VT, d. Hickory, PA.
          Isaac Ball, b. Brookfield, MA, d. Athol, MA.
          Isaac Ball, b. Framingham, MA, d. Athol, MA
          Benjamin Ball..... etc.

          The connection to Athol MA was what got me curious. I have a few generations of close family connections in and near Athol. So I just started doing some searches. Wives included Cummings and Howe surnames and those names connected my earlier research to Lucy.

          Over time, you get to know many more key surnames in your family tree and these names lead to connections sometimes. When I started out, I looked for a a half dozen surnames. Now I have a few hundred key surnames in mind and an idea of when and where that surname connects.

          Perhaps we are a bit closer than 43rd cousins. I can't even be sure that my Charlemagne link is valid. But I can be sure that my connection to Lucy is valid. I've even touched some of the original Athol vital record books in Athol. And I've found cemetery markers of Ball relatives. And THIS is exciting to me.

          I hope you can find your own connection into Lucy's family. It's not likely that your common ancestor will be through John Howe, but if it is, then you could be a cousin of the inventor, Elias Howe. I am his 5th cousin, five times removed.

          Turns out that Lucy is Elias Howe's 6th cousin twice removed.

          And this is why I went into so much detail.
          This shit is addictive.

          Good luck, cousin.

          "Never wrestle with a pig: you get dirty and the pig enjoys it"

          by GrumpyOldGeek on Wed Aug 13, 2014 at 07:38:10 PM PDT

          [ Parent ]

      •  Related to Sarah Palin? (1+ / 0-)
        Recommended by:


        t'd be a different issue if you were closely related genetically and she had two heads and four boobs.
        And this would make her weirder than she is just HOW???
  •  We all come from Adam and Eve, right? (21+ / 0-)

    Actually we all have two common ancestors;

    Genetic 'Adam' and 'Eve' uncovered

    Almost every man alive can trace his origins to one man who lived about 135,000 years ago, new research suggests. And that ancient man likely shared the planet with the mother of all women.

    The findings, detailed Thursday, Aug. 1, in the journal Science, come from the most complete analysis of the male sex chromosome, or the Y chromosome, to date. The results overturn earlier research, which suggested that men's most recent common ancestor lived just 50,000 to 60,000 years ago.

    Despite their overlap in time, ancient "Adam" and ancient "Eve" probably didn't even live near each other, let alone mate.

    Interesting diary, thanks.

    Daily Kos an oasis of truth. Truth that leads to action. UID: 9742

    by Shockwave on Tue Aug 12, 2014 at 05:49:58 PM PDT

  •  LOL ur video sort of called queen of denmark an (4+ / 0-)
    Recommended by:
    Shockwave, MT Spaces, NYFM, Rogneid


    Great diary  T&R

  •  Counting Ancestors - The One Trillion Principle (15+ / 0-)

    Everyone needs to understand this simple arithmetic and the implication:

    We are ALL one family.  

    The One Trillion Principle

    •  Nice (4+ / 0-)

      I really like that the author updated the website, quoting Ralph and Coop, who have the genetic proof.

      Sadly, for forces of division, the one trillion principle isn't enough. They want to pretend that this just means that only ancestors from their part of the world repeat millions of times. This is, of course, nonsense.

      •  Thanks. (0+ / 0-)

        "Pretend" being the keyword because the simple arithmetic is too much to ignore.

        I published the webpage quite some time ago.  It has taken a while for this idea to mainstream.  I'm pleased to see other anthropologists working on the same idea in a serious manner.

        For a while, I was being constantly harassed via e-mail because someone rallied people against me online.  The problem was acceptance of the idea that "the races" haven't been separate all this while.

  •  Why, None. (3+ / 0-)


    What a cool problem.

    We are called to speak for the weak, for the voiceless, for victims of our nation and for those it calls enemy.... --ML King "Beyond Vietnam"

    by Gooserock on Tue Aug 12, 2014 at 06:29:52 PM PDT

  •  Great diary. (8+ / 0-)

    However, and on a lighter note, it reminded me of an observation once made by that vaunted professor of urban geneology, Richard Pryor.  To wit:  "There is not enough f*ckin' goin' on!"

    I've often wondered when the first homo sapiens was born who would grow up to have a basic understanding of cause and effect.  Because it seems to me that the origin(s) of human intellect would be based on that.  And did that come from a genetic mutation, or a singular genetic pairing, or, perhaps, both?

    Anyway, interesting stuff.

    "What are we afraid of, and why are we holding back, when nobody's gonna listen to this shit anyway?" -- magic mitch

    by oldmaestro on Tue Aug 12, 2014 at 06:34:32 PM PDT

  •  there's a name for this (12+ / 0-)

    it's called 'pedigree collapse'.

    One site to start with, more reliable than most, is Genealogics. (It has a lot of people it its database who are well-known.)

    (Is it time for the pitchforks and torches yet?)

    by PJEvans on Tue Aug 12, 2014 at 06:39:51 PM PDT

  •  Charlemagne is my Great...grandfather (4+ / 0-)
    Recommended by:
    Ruby JM, craigkg, FarWestGirl, Rogneid

    at least 24 times, in various permuatations.

    El Cid also features.

    Be of good comfort, Master Ridley, and play the man; we shall this day light such a candle by God's grace in England as shall never be put out.

    by Bollox Ref on Tue Aug 12, 2014 at 06:43:03 PM PDT

    •  The most remarkable thing about our descents from (17+ / 0-)

      Charlemagne is not the fact of our connection but our ability to prove it. And that says a lot more about the intermediate generations than it does about is or Charlemagne.

      I can trace this as well.

      It means that our 17th through 20th century ancestors were in nice places where records are well-preserved, probably literate, and most likely comfortable. It also means that our 9th through 16th century ancestors were well-known people and certainly well-off.

      At least that subset of our ancestors. Plenty of others were serfs.

      Also, Charlemagne and El Cid surely have millions of unrecorded descendants whose lines go through ravaged colonial landscapes and Industrial Revolution slums, and they are likely to be everywhere from a Maya village in Guatemala to Angola.

      •  Oh, yes, well said (7+ / 0-)

        My link to Charlemagne is via Henry, Cardinal Beaufort, my 17th great.......... grandfather.

        Other than that, we've been pretty impovished.  But proud of being distant cousins of Lord Nelson and the Duke of Wellington.

        Be of good comfort, Master Ridley, and play the man; we shall this day light such a candle by God's grace in England as shall never be put out.

        by Bollox Ref on Tue Aug 12, 2014 at 07:17:37 PM PDT

        [ Parent ]

        •  Henry Beaufort's father, John of Gaunt (3+ / 0-)
          Recommended by:
          edwardssl, RiveroftheWest, Jay C

          would in today's dollars, be the 6th richest person in history.  Sorry he didn't leave you any.  His daughter, Joan Beaufort (my 15th g-grandmother), married Ralph Neville.  The Wars of the Roses were largely fought by the grandchildren of John of Gaunt.  His son Henry Bolingbroke became Henry IV.  His eldest son Edward married Joan of Kent and had Richard II.  The Tudors, Henry VII and Hanry VIII were great grandchildren of John's brother.  

          So we're very distant cousins.

          "There are times when even normal men must spit in their hands, hoist the black flag, and begin slitting throats." - H.L. Mencken

          by rwgate on Wed Aug 13, 2014 at 05:51:45 PM PDT

          [ Parent ]

          •  Greetings Cousin (0+ / 0-)

            Great-Aunt Joan was a remarkable woman (see number of children).

            My favourite Beaufort is Thomas, Duke of Exeter, Henry's younger brother.  Leading general for Henry V, who died young.  Cardinal Beaufort felt his loss, as he did for his eldest brother John who died even earlier.

            Be of good comfort, Master Ridley, and play the man; we shall this day light such a candle by God's grace in England as shall never be put out.

            by Bollox Ref on Thu Aug 14, 2014 at 07:51:25 PM PDT

            [ Parent ]

      •  Well met, cousins. (nt) (3+ / 0-)
        Recommended by:
        FarWestGirl, Rogneid, edwardssl


        Freedom is not just a word. 'Freedom' is a noun.

        by intruder from Old Europe on Tue Aug 12, 2014 at 09:25:20 PM PDT

        [ Parent ]

        •  Any two random people with New England ancestry (4+ / 0-)

          are something like ninth through twelfth cousins.

          This unfortunately includes the ones you don't want to invite to Thanksgiving dinner, like Palin, Bush, Cheney ...

          OTOH, cousin Barack is welcome to show up, though there are a few things I'd want to argue with him about.

          The thing about quotes on the internet is you cannot confirm their validity. ~Abraham Lincoln

          by raboof on Wed Aug 13, 2014 at 11:14:36 AM PDT

          [ Parent ]

      •  If you have New England colonial ancestry (3+ / 0-)
        Recommended by:
        RiveroftheWest, Rogneid, edwardssl

        (and that's a lot of us) you'll have several hundred immigrant ancestors living circa 1630-1650.

        All you need is one of them with upper middle class connections (such as ministers, lawyers, government officials) and you'll get a line from them to minor nobility to major nobility to royalty to Chuck.

        I have about five or six of those ancestors that I know of .

        And those New Englanders were fanatic about keeping and saving records, so if you can get back to someone there in the early nineteenth century.

        The thing about quotes on the internet is you cannot confirm their validity. ~Abraham Lincoln

        by raboof on Wed Aug 13, 2014 at 11:12:09 AM PDT

        [ Parent ]

      •  It means their church records survived. (0+ / 0-)

        Catholic baptisms were recorded, as were marriages.  What we are tracing is our Catholic ancestors.  Researching my European ancestry in the Duchies of the Low Country, when we see a non-Catholic marry a Catholic, baptism and marriage at the same time, there usually is no record of the non-Catholic line before the conversion because the only records are the church records.

    •  24! Pfft! (3+ / 0-)
      Recommended by:
      Ruby JM, Rogneid, edwardssl

      That's nothing. My guess would be that HIRH Prince Amedeo of Belgium, Archduke of Austria-Este and his siblings (all the children of HIRH The Archduke of Austria-Este (Lorenz von Habsburg-Lothringen)  and HRH Princess Astrid of Belgium)  has the most provable and he's got around 3 to 4 billion.

      My own 53,775 lines from Charlemagne is a couple of orders of magnitude away from qualifying as "statistically significant."

      "Lesbian and gay people are a permanent part of the American workforce, who currently have no protection from the arbitrary abuse of their rights on the job." --Coretta Scott King

      by craigkg on Tue Aug 12, 2014 at 10:09:56 PM PDT

      [ Parent ]

  •  None, thanks to my trusty DeLorean (10+ / 0-)

    and a loose set of morals.

  •  23andMe and other similar genetic mapping services (7+ / 0-)

    have a problem in identifying genes  with SNPs (Single nucleotide polymorphisms) unique to Native American populations. Possibly this is due to cultural ways or economics with fewer Native peoples using or contributing to the data base.  But there may be a darker reason. Many people have remarked that although they have anatomical traits rather unique to Native American populations they have only a small % of identifiably native genetic heiratage in that data base. Instead many have a set of genetic markers that are identified as Asian. Actually in most cases these are markers that appeared before the migration of Native ancestors into the Americas. And the dark reason that there is a lower genetic identity of out bred Native American decendents with many living Native Americans is that many branches of these peoples have been deleted forever by the efficient genocide from disease and by mass murder. A lot of mass murder.

    Life is just a bowl of Cherries, that stain your hands and clothes and have pits that break your teeth.

    by OHdog on Tue Aug 12, 2014 at 07:10:53 PM PDT

    •  I have wondered about that. (3+ / 0-)
      Recommended by:
      edwardssl, RiveroftheWest, Oh Mary Oh

      “Judge: Are you trying to show contempt for this court? Mae West: I was doin' my best to hide it.” ― Mae West

      by Rogneid on Wed Aug 13, 2014 at 05:13:28 PM PDT

      [ Parent ]

    •  mta research has id'd genes for NA natives that (0+ / 0-)

      `exist no where else, there is current research showing mdna from 10000 yr old bones in west BC that match current residents dna, they match the Chumash as well to that region, based on ancient dna extracted from bones and teeth.

      The rersearcher has id'd 5 strains and  showed that these strains or whatever they are actually called, now expanded to 15 by other researchers..existed only in the new world, some found in asia were from the new dna created by the people in the glacial refugia of Beringia, they later migrated east as well as west when they could.

      It also shows a pattern of west coast us migration as important..the 'kelp hiway' thesis.

      what this means is that the people of the new world were genetically unique by the time they actually populated the continent. This is current research probably soon to be published by a widely published researcher...I am talking out my memory/butt as it was a talk I went to, not something I even read..

      and further complicating all that is the 50,000 year old bones found on Santa Cruz Island, calif, and in a cave in southern Chile....don't know if dna extracted from those..there are other anomalies like the Kennewick Man and other odd findings indicating that there was several paths to the new world...and we know people have floated for many ,months, years even on shipwrecks.

      I think the ability to study mitiochondrial dna is going to change a lot about what we think we know about when and where people come stay tuned :>

      This machine kills Fascists.

      by KenBee on Thu Aug 14, 2014 at 03:01:00 PM PDT

      [ Parent ]

  •  One of my favorite throw-away lines from Vonnegut: (16+ / 0-)
    She was a direct descendent of the Emperor Charlemagne.  Of course, anyone with any European blood was a direct descendent of the Emperor Charlemagne.
  •  I have often heard it repeated (5+ / 0-)

    that there are more people alive on the planet today than have previously lived. But you are talking billions in the Paleolithic and six billion ancestors in just the past 12,000 years - which does not include the many lines which died out.

    Is there any confirmation in the historical and archaeological record that this many people actually lived in the past, or does this indicate that your presumptions are flawed and in fact, we have far fewer ancestors (are far more "inbred") than you speculate?

    •  That oft-repeated idea has been debunked, though (10+ / 0-)

      Carl Haub at the Population Reference Bureau did this by estimating birth rates (different in different eras). High infant mortality, particularly in the distant past, means that there were certainly more people living in the past than today. He came up with about 7 billion alive (in 2011), 100 billion deceased.

      Of course, people subject to infant mortality do not become ancestors. I estimated this at 50% not having any descendants today. It looks higher than that on the logarithmic scale.

      You're right that it could be higher. Even 70% producing no grandchildren, though, let's say, up to historical times when we know that's too high, still produces numbers in the billions.

      However, Nathan Keyfitz did something similar, earlier, with different assumptions, using an exponential growth model based on scholars' population estimates and then integrating the area under the curve to come up with the number of person-years, then dividing by life expectancy. I used the same method for the video. It's a little cleaner, and if you trust demographers' spot estimates, it has to be accurate. Again, even if you reduce life expectancy before the modern era to 15 or so, and there's not evidence of that from contemporary hunter-gatherers, you'll only halve the 6 billion to between 2-3 billion

      Both, by the way, came up with something like 100 billion humans (Haub since 50,000 BC, Keyfitz since 1,000,000 BC). Most of those humans didn't live for very long, but even those who lived to adulthood have to be well above today's.

      Thanks for the input!

      •  Something doesn't seem right here. (0+ / 0-)

        Genetic evidence suggests that Human population size fell to about 10,000 adults between 50 and 100 thousand years ago. From there, for most of our history, population growth was very slow. Nomadic tribes could only support a very small growth rate since they were limited by what the land could provide (plus predation, etc.). The advent of farming allowed a greater growth, but still limited. Cities of ancient Egypt allowed more... as technology advanced population growth increase became viable.

        •  Haub ignores the time before 50,000 BC, (0+ / 0-)

          and really is faking most of the subsequent 10,000 years, because his model starts with 2 people at 50,000 BCE and then has it gradually go up to 5 million at 8,000 BCE using the exponential growth formula. In that interval he has a billion people being born. That's only 23,810 per year, but of course it won't be even, as more will be born toward the end.

          My own calculations actually ignore everywhere before 10,000 BCE, because I want to base it on the best data and estimates we have from historical demographers--and they don't do a lot on the Mesolithic and before.

          The reason it's possible that we could have as many as 100 billion is infant mortality rates. Haub has 28 million births per year (on average, it's actually on a population growth arc) in the 1200 - 1650 interval, when world population was a bit less than 500 million. This is based, presumably, on the percentage of fertile women who will have given birth in that year. Out of 250 million females, maybe a third were of childbearing age and a third of those actually had a child.

  •  Republished to Genealogy and Family History (15+ / 0-)


    We've talked about this subject a number of times in our Friday Open Thread diaries, but I love the way you present it.

    Fascinating, ain't it?

    I worked on a tree of a friend of mine, who's German ancestor comes from a parish that has surviving church books going back to at least the mid-1500s.  In the process of tracing back the different branches (creating more and more branches), after about 350-400 years, I began to run into the same ancestors from different branches, causing the branches to collapse.  When I finished going back as far as I could with just the church books, the family "tree" resembled an hourglass.  If I could have traced further back, it would have resembled a smaller hourglass.

    So I was able to illustrate the collapsing family tree, which shows we all are the result of in-breeding - mostly quite distantly, of course.


  •  As someone who has done a lot... (10+ / 0-)

    ...with royal genealogy this is quite interesting.  Just as noted above the European descent from Charlemagne I believe most English descend from William the Conquerer.  Of course you could probably prune back a lot of these trees if you discounted illegitimate issue.  There are currently more than 4000 people alive today who qualify as heirs to the British throne per the Act of Settlement.  I compiled a project over the past few years of some 25K names among European royals, which wouldn't be nearly as interesting if they had not intermarried.

    •  And Karin Vogel is dropping fast (4+ / 0-)
      Recommended by:
      Ruby JM, FarWestGirl, Ahianne, edwardssl

      She's was the last person in the line of succession as of 2011 with 5752 people ahead of her. There have been a few additional births since then, including HRH Prince George of Cambridge.

      "Lesbian and gay people are a permanent part of the American workforce, who currently have no protection from the arbitrary abuse of their rights on the job." --Coretta Scott King

      by craigkg on Tue Aug 12, 2014 at 09:40:25 PM PDT

      [ Parent ]

      •  I wonder which is growing faster... (4+ / 0-)
        Recommended by:
        craigkg, FarWestGirl, Ahianne, edwardssl

        descendants of the Electress Sophia, or the world population.

        Once population peaks and starts declining (hopefully), the line of succession will grow faster, and trend toward world population. Unless we go off planet, speciate, stop keeping records, etc.

        •  My guess would be world population... (4+ / 0-)
          Recommended by:
          Ruby JM, FarWestGirl, Ahianne, edwardssl

          by a lot. The royals at the very least seem to be reproducing more slowly and having fewer children. Of course that's likely also true of the non-royal descendants since it is the general trend in most western industrialized nations.

          "Lesbian and gay people are a permanent part of the American workforce, who currently have no protection from the arbitrary abuse of their rights on the job." --Coretta Scott King

          by craigkg on Tue Aug 12, 2014 at 09:52:03 PM PDT

          [ Parent ]

          •  Yes. World total fertility now 2.41 (3+ / 0-)
            Recommended by:
            FarWestGirl, edwardssl, craigkg

            per woman and falling (World Bank) though.

            Then again even George V's descendants born in the 60s and 70s have 27/13 ~ 2.04 so far, and probably not growing much, and I expect it will be lower in the 80s cohort, and the line of succession as a whole will be similar to overal European growth.

    •  My late mother became interested in family history (2+ / 0-)
      Recommended by:
      Ahianne, edwardssl

      years ago and was discussing it one day with my husband who had some English ancestors. My uncle joined in, saying "Well then, you're related to Robert the Bruce -- everyone in England is." The next time they got together my husband admitted that, yes, he did seem to be related to Robert the Bruce, which filled my uncle with glee.

      Later my mother discovered that her parents were first cousins so her genealogical search was made way easier....

  •  If you meant to ask how many 'identifiable' (5+ / 0-)

    ancestors we have, then that is an interesting question.

    As far as how many total ancestors we have, that's just simple math and the answer is, we all have approximately the same amount of ancestors, give or take how many had children at very young ages.

    All of our ancestral roots go back to the beginning of life on the planet.

    We are all related to each other if you go back far enough along the chain.

    Ancestor: a person, typically one more remote than a grandparent, from whom one is descended
    The operative word is descended, in other words, born from. It may not be realistically feasible to trace your ancestry back past a certain point, but one thing is certain, your ancestry traces all the way back to the beginning of life.
    •  Agreed on the beginning of life (3+ / 0-)
      Recommended by:
      kurt, Ahianne, edwardssl

      People don't appreciate how arbitrary any definition of "when humanity began" is. From the perspective of people at the time, nothing was beginning. Speciation is gradual.

      You don't buy the idea, though, that people who are from more isolated communities, like uncontacted peoples, or who are part of in-marrying groups, will have far fewer ancestors in the short term?

      The point of my video is exactly yours. We all share the same ancestors after a few thousand years, at most. It's the more recent few thousand that make a slight difference. If I am from one small community in South India that has a near-requirement of first cousin marriage, my ancestors grow more linearly than exponentially, while if you are a Hawaiian with ancestry in South China and New England and Puerto Rico and many other places, your ancestry may grow faster, reaching the total human population quite a bit faster. Or, consider the possibility that Tasmania was truly isolated for 25,000 years. Native Tasmanians, when full Native Tasmanians existed, might have had an ancestors limit that was perhaps 100,000, until  a time when the human population was much lower.

      So there might be a difference in billions.

      Still, it makes no difference, because we re all united.

      If the question is how many you can identify, that's mostly a function of how many of them had money or lived in a literate, well-ordered civil society.

      •  I'm not sure that isolation has a huge effect (1+ / 0-)
        Recommended by:
        Jay C

        as far as ancestors go.  They came from somewhere, a common family tree and became isolated well after humanity began. They may have been isolated for some small part of human history, but the number of ancestors still build up at approximately the same rate whether a community is isolated or not.  It all depends on how fast the generations go by and how young the mother was when she had the child and how long it took for that child to procreate.

         Your great-great-great grandfather's sister is not your ancestor.  Only your great-great-great grandfather and grandmother are your ancestors.

        Ancestor: a person, typically one more remote than a grandparent, from whom one is descended
        Let's say nobody ever intermarries.  Then you have a static amount of ancestors in a direct line back to the beginning of life.

        Once you bring intermarriage into the equation, it seems to me like people out in the larger population would have more ancestors than isolated communities.  My parents might share a common mother 1000 generations ago which would add approximately 1000 ancestors to my count since this would be a new and distinct line back through time to that original mother.

        Isolated communities would not have this happen, they would be severely limited to the number of lines created back to the point that they first became isolated, but then would have the same chance as all the rest of us from that point back.  So I agree that in the short term, isolated communities would have less ancestral lines.

        Isolated communities would in effect have a 'choke point' at the time they became isolated, limiting the number of ancestral lines, but back beyond that they would share a common ancestry with us all.

        It is fascinating, because once that tribe stopped being isolated, the very first marriage outside the tribe would likely result in a common ancestor in the general population and they'd catch up in an instant with their first child who would then have a new line back to a very, very distant common ancestor.  And if only one person in that isolated tribe, at any time during that 25,000 years had contact and bore a child with another tribe, then all that isolation would be for naught.

        While the definition of the beginning of man is rather arbitrary, one thing is for certain.  All living human beings on the planet can trace their roots back to two individuals at some point in history no matter how you define the beginning of humankind.

        •  I agree with everything, except for the two (0+ / 0-)

          individuals being human. Before the identical ancestors point, we are descended from every human who has descendants. Let's say that was 10,000 people. Those 10,000 people were never descended from 2 people. They were descended, millions of years back, from, say, 100,000 individuals who are also the common ancestors of chimpanzees and bonobos.

          Speciation doesn't occur in an instant, with a parent being of one species and a child being of another species. Rather, reproductive isolation separates populations over time. 1,000 individuals on this side of the valley eventually were ancestors of only humans and no chimpanzees--6,000 individuals on that side of the valley eventually were ancestors of only chimpanzees and no humans... But they certainly weren't aware of it at the time.

          If it ever goes down to two organisms, those two organisms were the brother and sister single-celled organisms who were the first to develop whatever mutation led to sexual reproduction.

    •  Amending the question to "How many 'unique' (1+ / 0-)
      Recommended by:

      ancestors..." changes it considerably and makes it much more difficult to answer. Cousin marriages and various other consanguineous unions or encounters reduces the number of uniques significantly.

      Information is abundant, wisdom is scarce. ~The Druid.
      ~Ideals aren't goals, they're navigation aids.~

      by FarWestGirl on Wed Aug 13, 2014 at 05:42:00 AM PDT

      [ Parent ]

      •  One family of first cousins is closer than others (0+ / 0-)

        in my immense family (my fraternal grandparents have over 1,000 direct descendants already) because my uncle and his wife share an ancestor.  In other words, they have the same great-great-... about eight generations before they married.  So those first cousins are also distant cousins on their mother's side, making them one-half related plus the other fraction.

        Not all of our first cousins are equally related to us.

    •  Born? Or hatched? (1+ / 0-)
      Recommended by:

      Give or take 250 MYA.

      To be on the wrong side of Dick Cheney is to be on the right side of history.

      by mbayrob on Wed Aug 13, 2014 at 08:07:25 AM PDT

      [ Parent ]

  •  Going back, say, 200,000 years... (3+ / 0-)
    Recommended by:
    Ruby JM, kaliope, edwardssl

    At 20 years per generation, you have 10,000 generations, and 2 to the 10,000 power is about 10 to the 3010 power. Looks like most of your ancestors at that remote time would not be unique. I'm pretty sure somebody above must have done the same calculation but I thought I would too.

    Moderation in most things.

    by billmosby on Tue Aug 12, 2014 at 08:59:56 PM PDT

    •  I'd go a little further (4+ / 0-)
      Recommended by:
      billmosby, kaliope, FarWestGirl, edwardssl

      especially for some people. If you have ancestry mostly from a small village, or an isolated island, most probably aren't even unique after 10 generations.

      Then again, why not go further? There's no real dividing line between species as you go back in time, so let's follow Dawkins' Ancestors Tale and calculate 2 to the 20 millionth power to get back to our common ancestor with mice, or 2 to the 500 millionth power to cover all the chordates?

    •  The length of generations changes over time, as (2+ / 0-)
      Recommended by:
      billmosby, edwardssl

      well. With an average lifespan of 30-35 years, the age at first offspring drops from 20 to about 15 years. Admittedly, family size was greater, but not all families spanned a decade or more, there were many who died in the first childbirth & infant mortality was a huge factor. Most offspring were born to teenaged mothers for most of history and most definitely prehistory.

      Information is abundant, wisdom is scarce. ~The Druid.
      ~Ideals aren't goals, they're navigation aids.~

      by FarWestGirl on Wed Aug 13, 2014 at 05:46:57 AM PDT

      [ Parent ]

      •  And in Mormor pioneer country to this day... (4+ / 0-)

        teen motherhood very often provides young women with an escape from caring for their mothers' young children.

        Which also brings to mind a recent appearance (Tonight show? Conan?) by Whoopi Goldberg, who commented on her fairly recent status as a great grandmother. She said her daughter was bemoaning her own impending early grandmotherhood, upon which Whoopi retorted "You made me a grandmother at 33- I have no sympathy for you whatsoever."

        Moderation in most things.

        by billmosby on Wed Aug 13, 2014 at 08:03:30 AM PDT

        [ Parent ]

      •  Length of generations (2+ / 0-)
        Recommended by:
        RiveroftheWest, FarWestGirl

        differs in families as well.  On my father's side, it was the youngest of numerous children I'm descended from, while on my mother's side it's usually one of the older children, with their parents having married at an earlier age than my father's  did.  So there's at least one more generation on mother's side since my father's grandfather was born.
        My mother's side seemed to descend from daughters in some lines, so we lost names and gained new ones when those girls married.  Her father's line went back much farther with the same name than her mother's.  Makes for a strange looking tree!
        And of course we have those lines that have no records available, like father's line in Co. Donegal, Ireland, with a group of children born in the 1790s but no parental information to be found.  Or a g-g-g-grandfather with a common name and only a state birthplace known!

  •  a back-of-the-envelope calculation (2+ / 0-)
    Recommended by:
    Ruby JM, edwardssl

    Assume half of the people alive 2,000 years ago have any descendants alive today (hence are ancestors of everyone alive today).

    From there back, just multiply the world population of parents by the number of generations in 8,000 years (10,000 - 2,000).

    At 25 years per generation, we get 320 generations.

    World population of parents in each generation was roughly 10 million, so we get about 3 billion for the 10K to 2K era.

    Then add in the ancestors for the past 2,000 years, during which the population grew as we approach the present.

    To a rough approximation, we can assume the population of parents was about 100 million per generation, or about 10 billion overall.   But we have less density of ancestors for that group, so reduce it to maybe 5 billion.  

    Adding, we get about 10 billion ancestors within the past 10K years.

    Then of course you need to go back a few billion years counting a LOT of single-celled ancestors dividing every 20 minutes, so good luck figuring that out.

    •  I actually kept going up to our primate/rodent (3+ / 0-)
      Recommended by:
      sawgrass727, JMcDonald, edwardssl

      common ancestral species, the progenitor of Euarchontoglires, using Dawkins' generation lengths and contemporary rodent effective population sizes...

      but those trillions were bad enough... and a bit silly to make the cut for the video. Let alone bacteria-like ancestors!

      I love the simplicity of your "spherical cow" calculation. Are you a physicist by chance?

      2,000 years is very late for an identical ancestors point though. It's about right for where Rohde, et al. find our MRCA (most recent common ancestor) though. That doesn't really change your assumptions too much though.

      BTW, 10 billion is what I got using the calculus version, when I assumed very high ancestor growth rates, which are probably true for populations that have been urbanized for centuries or millennia, yet not organized tribally, like the Yellow River valley or northern Italy.

      •  thanks (1+ / 0-)
        Recommended by:

        I'm a computer scientist, not a physicist, but I have a rather good background in the hard sciences.

        One thing I learned from physics is that you can often find good solutions by abstracting outward, ignoring the details.  Conservation arguments are the epitome of that kind of reasoning, but spherical cows are also useful.

        In general, it pays to do an order-of-magnitude argument that is quick and simple as a check on more detailed calculations, lest you add or subtract a few orders of magnitude by mistake.

        I agree that 2,000 was a bit late -- 3K or 4K would likely have been better, but as you note it doesn't change much.

        Interesting that we got such similar results.  (I did my calculation after reading just the first paragraph of your diary, to avoid being influenced by your approach...)

      •  A physicist would have said (1+ / 0-)
        Recommended by:

        "spherical cow in a vacuum" . .. .

        I love the simplicity of your "spherical cow" calculation. Are you a physicist by chance?
  •  Salt Lake City is crazy about genealogy ... (3+ / 0-)
    Recommended by:
    Ruby JM, FarWestGirl, edwardssl

    ... and basketball.

    Lots of immigrants have come here since the days of 1847.

    However, the bigger world-picture is so much more fun -- thanks!

    Millions of us – the majority – must come together to insist that President Obama and the Democrats stand up and fight for the things we sent them there to do ... Michael Moore

    by MT Spaces on Tue Aug 12, 2014 at 09:05:37 PM PDT

  •  You cannot know what this might mean to (12+ / 0-)

    an adoptee.  As an adoptee from another country, I thank you for this intriguing diary.

    Especially so this bit:

    We do not all share the exact same number of ancestors, but it is clear that we all share the majority. 5,000 years ago, you could find your ancestors in any village on the planet. Today, their descendants, your cousins, are everyone you know .
    As a child in the 1960's, I accompanied my adopted mother on many journeys as she gathered genealogical information about her family for publication.  One of her cousins assisted in the venture which took a couple of decades-perhaps closer to 30 years.  

    No internet or cell phones back then, instead days of travel to find grave sites & records & leads across countries & then typing it all up on a manual typewriter.  Criminy, even obtaining identities of ancient photos was labor intensive back then.

    During a research project recently, I stumbled upon her  family tree on some gen website that some distant unknown family member had started & others added to.  It was not complete & yet I was astonished to see that this "tree" was pages & pages & pages long (they had put an actual tree up..).  

    Unfortunately, I bookmarked the site on a computer that crashed & now have no clue what site it was.  I so wish I could recall it so I could offer the now out of print book to whoever is trying to do this history...

    It was impossible for me not to contrast that memory & childhood ones with the reality of the tree I assembled for my adult kiddos.  Their fathers side has been researched on their end back to around 1300 & so has many branches.  While their mother's side begins in 1952 with me.  I think I will add linkage of your diary to my branches so it won't look so lonesome & lopsided..... :)

  •  This is not the best/easiest approach (4+ / 0-)

    Google "Genetic Diversity", "Population Genetics" & "Effective Size" - the data has already been gathered and the calculations complete. More data just refines the accuracy of the answers. Think about the problem from the perspective of number of alleles at each locus to get the "effective size" of the population - thinking about unique kind of leads you down the wrong alley.

    Also, during the Upper Paleolithic transition the human population dwindled to an effective size of 10,000. That's as close to extinction as a candle guttering in a gale. So that's the quickest answer to your question. The basic takeaway is that humans are the most inbred species on the planet (excepting Cheetahs because of our hunting).

    Other good topics to look into, if you're interested, are Mitochondrial Eve and Y-chromosomal Adam as these give an elegant shortcut to several of the questions you touch on. BTW Stoneking & Cann used the wrong approach in rooting the tree of their M. Eve, unfortunately while we have enough data there isn't enough time in the universe to crunch the numbers - we're waiting on a theoretical breakthrough (very unlikely) or a computational break through (almost guaranteed).

    If you have access to journals I cannot recommend a better guy to read than Paul Sharpe

    A corporate duopoly indeed.

    by gendjinn on Tue Aug 12, 2014 at 10:05:49 PM PDT

    •  Thank you. I wasn't really trying for a genetic (3+ / 0-)
      Recommended by:
      FarWestGirl, Linda Wood, edwardssl

      answer though, for this particular experiment, but rather a genealogical answer.

      I grant that this collection of individuals is scientifically meaningless, from the perspective that individuals are merely carriers of alleles. I mean, the probability is that we don't have a single gene from a particular 15th generation ancestor.

      Genealogy, in this sense, is hardly a scientific pursuit. It's a cultural pursuit. I like to point out, also, that if there is an average non-paternity rate of 5%, which is low, the probability that your on-the-record father is your biological father is 95%. The probability that your 14th generation patriarch is is less than 50%. The probability that your 45th generation male ancestor actually is is less than 10%.

      Again, thanks for the recommendations.

      One question I have: was our Y-chromosome Adam already the Y-chromosome Adam of Mitochondrial Eve's generation?

      •  Your question, (3+ / 0-)
        Recommended by:
        edwardssl, Ruby JM, RiveroftheWest
        ... was our Y-chromosome Adam already the Y-chromosome Adam of Mitochondrial Eve's generation?
        is difficult for me to get my mind around.

        If we're all descended from Mitochondrial Eve, is the question that more than one Y-chromosome ancestor appears to have existed in that time period? Is it that the time period of origin of Mitochondrial Eve includes the time period for more than one Y-chromosome line? I'm lost. it's such a good question.

        Thanks for this diary.

        •  Well, the range in dates for both of them is large (1+ / 0-)
          Recommended by:

          but let's say that mt Eve lived 150,000 years ago and Y-Adam lived 300,000 years ago. They could have been this far apart. They could have been contemporaries. We're not sure. If they were very far apart in age, especially twice the distance, Y-Adam could already have been the universal male-line ancestor.

          I rather doubt this, actually, because of the diversity of Homo at the time. But it may be possible.

    •  Wine out of old bottlenecks (2+ / 0-)
      Recommended by:
      RiveroftheWest, edwardssl

      Since we interbred with non-H. sapiens populations, there were likely paths that do not go through that bottleneck.  I'm not sure it changes the calcs much.

      To be on the wrong side of Dick Cheney is to be on the right side of history.

      by mbayrob on Wed Aug 13, 2014 at 08:14:54 AM PDT

      [ Parent ]

  •  I've done my family tree (4+ / 0-)
    Recommended by:
    kaliope, kurt, FarWestGirl, edwardssl

    I have close to 950 direct ancestors. all from Norway. Here and there I have second or third or fourth cousins who married someone related to them.

    "Stupid just can't keep its mouth shut." -- SweetAuntFanny's grandmother.

    by Dbug on Tue Aug 12, 2014 at 10:16:30 PM PDT

  •  By the way, we all have more unique female (2+ / 0-)
    Recommended by:
    FarWestGirl, edwardssl

    ancestors than male ancestors because of women dying young in childbirth and their male partners remarrying.

    Unfortunately when smart and educated people get crazy ideas they can come up with plausibly truthy arguments. -- Andrew F Cockburn

    by ebohlman on Tue Aug 12, 2014 at 11:00:10 PM PDT

  •  Wild guess (2+ / 0-)
    Recommended by:
    Ahianne, Ruby JM


  •  I'm my own grandpa… (2+ / 0-)
    Recommended by:
    RiveroftheWest, Ahianne

    An hilarious song, done by several artists including Lonzo & Oscar, Ray Stevens, Willie Nelson, Homer & Jethro, and loads of others.

    LRod—UID 238035
    ZJX, ORD, ZAU retired
    My ATC site
    My Norm's Tools site

    by exatc on Wed Aug 13, 2014 at 07:00:17 AM PDT

  •  Re: cousin marriage (4+ / 0-)

    In some parts of the world--and specifically in the South in this country--cousin marriage led to very recent "doubling." I've got two lines w/cousin marriages in GA--only to discover both lines descended (through another cousin marriage) from the same immigrant to VA.  But the most interesting example of what cousin marriages do to a family tree is in my husband's family.  He's descended FIVE times from the same man in late 1600s VA. Sort of cuts down drastically on the number of ancestors possible. :)  Also makes for a very interesting pedigree chart!

    •  Five? (2+ / 0-)
      Recommended by:
      RiveroftheWest, edwardssl

      Only five? {Teasing.....}

      Yeah, I have one couple that's up to lots more than that ;-)
      Richard Gould married (around 1580) a woman named Mary. Their son Zacheus married Phoebe Deacon ~ my ancestors three different ways. Richard and Mary's daughter Priscilla married John Putnam ~ I've got 17 different lines back to them (continued research has added a few since the chart below...). Only one first cousin marriage to get those, although there were several 2nd/3rd/4th cousin marriages. Most are through one woman ~ Helen Putnam, my great-great grandmother ~ 9 of her 16 great-grandparents were Putnams (and a couple that weren't had mothers or grandmothers who were....).

      On the other hand ~ the closest my two Yankee grandparents were related was sixth cousins (and then seventh cousins lots and lots of different ways). They came from adjoining towns and both had deep roots in the area.

      As someone else said upthread, if you go back to colonial New England, you tend to be related to everyone else who does.....I've counted 53 couples married since 1600 (so Richard and Mary don't make that cut!) where I'm descended from two or more of their children (plus five others ~ two women, three men ~ with multiple spouses). Last of those marriages was about the time of the American Revolution.... But, as I said ~ closest my grandparents were related was 6th cousins (at least that I've found so far ~ there are a couple places I've still got gaps or question marks....).

      All those Putnams

      The worst sin - perhaps the only sin - passion can commit, is to be joyless. (Gaudy Night, Dorothy L. Sayers)

      by mayim on Wed Aug 13, 2014 at 12:14:19 PM PDT

      [ Parent ]

      •  Carlos II (the Bewitched) of Spain had you beat. (5+ / 0-)

        Half of his g-g-g-g-grandmothers were Juana la Loca of Castile. He was the poster child for the bad effects of royal inbreeding.

        •  How come Cleopatra VII was so healthy? n/t (5+ / 0-)
          •  Better luck with her ancestry? (4+ / 0-)

            The Ptolemies had not been inbred for as long as the Hapsburgs. Their original Macedonian ancestors were probably fairly diverse.

            Maybe there was some secret outbreeding going on, too. The pharaohs had been officially practicing incest for thousands of years, yet I don't know of any indications that they had problems with recessive traits.

            Finally, from what I know, there was more selection going on in Egypt. Cleopatra had to take out numerous close relatives to get to the throne. This had been going on for several generations. Someone like poor Carlos (or Juana) would have been eliminated early on. The Hapsburgs lived in an era where the monarch's right to the throne was usually undisputed.

            •  For one thing Ptolemy Auletes was almost certai... (0+ / 0-)

              For one thing Ptolemy Auletes was almost certainly illegitimate, and perhaps we know his mother's connection to the Memphite priesthood. I bet there were other instances. Good point about additional Macedonian diversity. She had Persian ancestry also through I think Seleucus I'd marriage.

          •  Cleopatra VII (The famous one) (0+ / 0-)

            was generally suspected, at the time (IIRC) of being genetically "suspect" - which, given that she was royalty, wasn't deeply investigated - the Ptolemies were notable for (in the Egyptian manner) "marrying" each other - what that had to do with their actual genetic heritage was usually left as an unexamined subject...  

  •  ANCESTORS (2+ / 0-)
    Recommended by:
    Ruby JM, edwardssl

    None.  I have no interest in the past.  In fact, except for my husband and daughter I have NO RELATIVES.  And, that is not a BAD THING at all.

    •  Yes you do! (3+ / 0-)
      Recommended by:
      edwardssl, dewolf99, RiveroftheWest

      We all have the same relative, a bacterium named Fred.

      "There are times when even normal men must spit in their hands, hoist the black flag, and begin slitting throats." - H.L. Mencken

      by rwgate on Wed Aug 13, 2014 at 06:12:24 PM PDT

      [ Parent ]

    •  No ancestors? (1+ / 0-)
      Recommended by:

      That seems a little sad to me, naoma.  My father was very family oriented and kept documents and pictures of everyone, thank goodness.  He loved having relatives visit, even just for a meal, and I remember so many happy times with family from his and my mother's sides.  There are only a few of us left now, but we still try to keep in contact though we live in different areas.
      Over my years of ancestor hunting, I've met through online message boards a dozen or more cousins of varying closeness, though only a few in person.  The history of my family has taught me and my children a lot about the history of our country and of the countries ancestors came from, and that's a good thing, I think.
      I don't think I'm closely related to any famous people, but that's not important.  I do know I had two g-uncles in the Civil War, one in the infantry and the other a cavalryman, and I found a book about the regiment the infantry major was in....another bit of history learned from genealogy.
      My son-in-law had a Scottish ancentor who joined the British army (no land available in Ross and Cromarty for third sons) and was in the Revolutionary War.  Another interesting bit of history....he was a prisoner and after being freed in 1783 he was given land in Nova Scotia.
      Hmmm....this post looks like bits from several history books, doesn't it, especially if I toss in the 49er g-g-grandpa!

    •  I am a rare type of genealogist. I don't identi... (1+ / 0-)
      Recommended by:
      rl en france

      I am a rare type of genealogist. I don't identify particularly with my own set of ancestors. That's rare for a genealogist. I'm far more interested in subjects like I just presented: the cultural contours of population movements, and how people understand and, yes, fictionalize and abuse them, through thinking 'bloodlines' matter and discounting individuals' freedom to prefer and live alternate forms of connectedness to humanity as a whole.

      Much respect.

      Ruby JM Aug 13, 6:15p

  •  Interbreeding in the south (0+ / 0-)

    Kentucky--Four million people; thirteen family names.

     If you divorce your wife in Arkansas, is she still yur sister?

  •  IAP (2+ / 0-)
    Recommended by:
    bartcopfan, RiveroftheWest

    What does IAP stand for? You use it in your diary?

    The Republican plan is always the same old trickle-down, on-your-own, special-interests-first, country-club, voodoo economics.
    Donate to Oxfam America for the famine in east Africa.

    by JayC on Wed Aug 13, 2014 at 10:44:15 AM PDT

  •  mathematical evidence that i've been right all (3+ / 0-)
    Recommended by:
    Rogneid, RiveroftheWest, Oh Mary Oh

    along, mankind is one kind, and one severely dysfunctional family.

  •  Get off the "of" (0+ / 0-)

    "I've never come across anyone who had this complete of a pedigree, all with unique ancestors."

    Unfortunately, I've come across far too many Americans who insert the utterly superfluous word "of" into locutions such as these, Ruby.

    It should read "...this complete a pedigree..."

    Perhaps you and/or some of your innumerable ancestors should have paid more attention in English class.

  •  Here's how I look at it (from my book on history): (5+ / 0-)

    A Small Number of Ancestors, A Multitude of Relatives

    In considering our ancestry, we need to remember how the coalescence process works. In coalescent theory, as we move back in time particular genetic traits will be found in a narrower and narrower population, until they are found only in a single individual. So as we go back in time, we see that we share more and more genetic ancestors with other humans. And, naturally, the number of humans alive in the past was far less than it is now. Therefore, the pool of possible ancestors narrows—coalesces—as we go back. Obviously a great many variables affect the way in which particular traits are distributed. Inheritance does not proceed in neat, chronologically regular sequences.

    We also need to consider the way in which our ancestors, hypothetically, increase geometrically in number as we trace them back through the generations. We each have two (biological) parents, four grandparents, eight great-grandparents, and so on. If we start with our parents and count them as step one, by the time we go back twenty steps,  we would each have 1,048,576 great (x 18) grandparents. At step 30, we would each have 1,073,741,824 great (x 28) grandparents. If we assume that a generation may be arbitrarily defined as 20 years, step 30 would take us back to the early 1400s. Since there were not one billion people alive in the entire world in the early 1400s, it is clearly impossible for each of us to have had a unique and distinct set of ancestors. We are obviously all related to each other, we obviously all share a great many ancestors. We are an enormous and very extended family. Where does that extended family really begin?

    If it were possible to reliably trace the origins of every section of chromosome in the human genome, any particular sequence of nucleotides, we would find, as we noted, that each section is ultimately traceable to a single person. So how many individuals are believed to have contributed to the genome of anatomically modern humans? Researchers in the early 2000s estimated that the total number of such individuals, the people who contributed all the DNA found in every human being alive in the world today, was about 86,000, two of whom were Mitochondrial Eve and Y chromosomal Adam.15 This number is fewer than the number of people living today in Hastings, UK, or Ghorashal, Bangladesh, or Rafaela, Argentina.16 If this figure is correct, it is this set of humans, living at diverse times in the past, who are the true ancestors of the family of anatomically modern humans.

    Read a preview of Volume One of my book here.

    by Yosef 52 on Wed Aug 13, 2014 at 02:08:27 PM PDT

  •  Complicating our DNA... (3+ / 0-)
    Recommended by:
    Linda Wood, Rogneid, RiveroftheWest

    ... is the reality that sometimes our ancestors are not who we THINK they were. Your great, great, great grandmother may have been adopted, and if it were a great, dark secret, even she didn't know. There may have been affairs and remarriages that contributed DNA you don't know you have. Some of your ancestors may have been orphaned or abandoned and grown up not knowing to whom they were related or where they came from.

    Humanity is a messy species. And since we're capable of lying with a straight face, there's potentially a LOT going on in ANY gene pool that the recipient of its complexities doesn't know about.

    •  Yes, I love to point out non-paternity rates. (2+ / 0-)
      Recommended by:
      Rogneid, RiveroftheWest

      Even if 5% of the fathers on record are not biological fathers, that makes the probability that any record-ancestor is your biological ancestor .95^n, where n is the number of fatherings that it takes to get from that ancestor to you. It only takes 14 fathers in a line to make the probability of biological ancestry less than 50%, and 44 to make it less than 10%.

  •  Unfortunately a lot of my ancestors (4+ / 0-)

    most likely would have been taken out from the Crusades and the Armenian genocide. Namely my grandmother, as in my mother's father's mom. I couldn't read the whole diary but I don't know what emphasis is placed on those situations. Especially when people change their names as well.
      Most likely my ancestry on my mothers side goes back to the Phoenicians. On my biological fathers side the Roman Empire. That's not saying much but it is Sicily and Calabria.

      On my other dad's side, it's German and German Jew. But his dad was a baron from Stuttgart I believe. Fortunately for my dad, and his mom everyone lived in Pittsburgh. My dad was born there.

    I want to be the next Secretary of Antics.

    by nellgwen on Wed Aug 13, 2014 at 03:03:17 PM PDT

    •  Coming from such central regions, and (4+ / 0-)

      being of diverse ancestry, you probably are on the higher end as far as your number of ancestors goes.

      Someone who only has German Jewish ancestry would have fewer total ancestors, as so many of the lines are repeated, back to the fairly small founding population of Ashkenazi Jews along the Rhine in the 9th century.

      However, Sicily has ancestry that is so diverse—Romans, Phoenicians on that side too, for sure, Arabs, Berbers, and ancient peoples that are none of these. The same is true of Calabria and Lebanon and the entire Middle East, since it has always been located in a highly mobile high population region. So you'll have lines that help you catch up to near the whole human population faster than others.

      •  Wow (2+ / 0-)
        Recommended by:
        Rogneid, RiveroftheWest

        That's very interesting. Kind of like being in the eye of the hurricane of genealogy. My mom's people were and still are in Syria, my dad was the Sicily and Calabria. My mom's second husband is the German and German Jew. So my sister has both Syrian and Jewish lines. And she's a Gemini born on the cusp. And she's so cuspian.

        I want to be the next Secretary of Antics.

        by nellgwen on Wed Aug 13, 2014 at 03:24:35 PM PDT

        [ Parent ]

        •  I wish them health and safety. When you said Ph... (1+ / 0-)
          Recommended by:

          I wish them health and safety. When you said Phoenician I'd guessed Lebanon, but Syria is of course right there. Are they near Latakia?

          Yes, it's cool that both of your sides are Roman and both Phoenician/Carthaginian in a way. I want to do a Rome/Carthage video at some point. Your sister also... Together you are like pan-West Eurasian.

  •  28 Year Generations? (2+ / 0-)
    Recommended by:
    Rogneid, RiveroftheWest
    28-year generations mean that we should expect our average 31st generation ancestors to have been born around the year 1117, when the population of Earth was less than 600 million. But the 31st generation requires more than 2 billion ancestral lines.

    Why assume that the average time from birth to reproduction is 28 years? Indeed, for most of the millions of years of human distinction from other species, sometime 17-20 years seems more like it. Even if the fertile years was something like aged 16-40, the average is 23.

    "When the going gets weird, the weird turn pro." - HST

    by DocGonzo on Wed Aug 13, 2014 at 03:43:31 PM PDT

  •  One Family (3+ / 0-)
    Recommended by:
    Rogneid, RiveroftheWest, Oh Mary Oh

    A positive result of my family history efforts has been the awareness that the person who just cut me off in traffic may be a cousin, and so may the person to whom I am tempted to be rude. Also, I read obituaries with an entirely different attitude.

  •  Exactly 1,273 unique identified direct ancestors (3+ / 0-)
    Recommended by:
    Rogneid, edwardssl, RiveroftheWest

    This number accounts for each unique individual ancestor I've recorded in my family tree limited to my parents and grandparents only. This number does not included uncles, aunts or cousins.

    That's out of about 90,000 individuals I've entered into my genealogy database. I've tried to limit this database to those who are related to me or my descendants in some way, directly, through marriage, or through adoption. I try to avoid entering orphan (unrelated) individuals.

    Generally, I try to limit my research to my own interests and avoid getting sucked into surname studies, royal lineage, and filling in all the descendents of all siblings and their children and their children, etc. Unless it's close family or people I know or have some other personal reasons for expanding my scope.

    So as much as I try to limit things within my own interests, my database is a limited subset of only 90,000 individuals - so far.

    This is about my ancestors and extended families and their lives as experienced in their own historical context. And that's a HUGE project.

    "Never wrestle with a pig: you get dirty and the pig enjoys it"

    by GrumpyOldGeek on Wed Aug 13, 2014 at 04:18:35 PM PDT

  •  Ancestors (1+ / 0-)
    Recommended by:

    I think that TOO many people, for whatever reasons, put TOO much emphasis on their ancestors. WHO CARES? I have the family records going back to the Middle Ages. I have a Jewish woman friend who told me that their family, living in Alexandria Egypt prior to the Diaspora, have family records going back to the 4-5thC!!!

    SO WHAT! As I have said many times: "Old family is great, but old family MONEY is better. No old family, no old family money....Heck! NEW money is just fine!".

    The ancient Romans worshiped their ancestors. Within anyone's home, be it palatial or humble, there was always "The Lares" tabernacle....a shrine devoted to the ancestors. Go out along the Appian Way where there are many of those old family tombs existing even today, and you see, outside the tomb itself, sometimes, a marble banqueting table and seats. Families would go out on special family occasions and share the festive meal, and wine (AND lots of wine if the old dead fools had left LOTS of money!!!) with those long gone.

    When I was young, I read a book we had in the Library at my Grandmother's house: "Daddy Long Legs". In it, the author describes a woman with whom she went to school. She said that this woman "just knew" that she was descended from THE finest apes.....long, silky coats etc.

    I don't give a damn if way back in primordial times my ancestors had long, silky hair. GMAB! It means NOTHING in the long run!

    •  For me, here's the way it is. I don't identify ... (2+ / 0-)
      Recommended by:
      RiveroftheWest, Oh Mary Oh

      For me, here's the way it is. I don't identify particularly with my own set of ancestors. That's rare for a genealogist. I'm far more interested in subjects like I just presented: the cultural contours of population movements, and how people understand and, yes, fictionalize and abuse them.

  •  I think this discussion may be very wrong? (2+ / 0-)
    Recommended by:
    Ruby JM, RiveroftheWest

    We have 46 chromosomes and generally they stay intact.
    (but not always)
    Let's assume you can generally get at a minimum, one chromosome per ancestor, so sort of, ultimately, you have a max of 46 ancestors at some remote time.
    One of my ancestors was named Luce (c.1640) and now there are 10-15,000 of his descendants in the USA -- this does not mean that I have any of his DNA, since he was on my mother's side.  If he was on my father's side. I'd at least likely have his Y chromosome.  Yes, this is hard to think about.

    •  Chromosomes do not stay intact, except the Y (2+ / 0-)
      Recommended by:
      RiveroftheWest, Oh Mary Oh

      All the others recombine.

      If Luce was your 13th generation ancestor, the percentage of your DNA that would be his, on average, would be 1 over 2^13, or approximately 1 8 millionth. But you only have about 19,000 genes. So the probability that Luce gave you any DNA is very low... but not zero.

      But in any case, this discussion is not about genetic ancestors, which, as commenters above have noted, are very few in number, since the early human population was so low.

      The discussion is about the number of people who could be considered your parents, grandparents, great-grandparents, and great (x n)-grandparents, whether or not they contributed any DNA to you. It's a cultural question rather than a scientific one.

  •  Our ancestors go back hundreds of millions (0+ / 0-)

    of years. Thousands. Back to when life first began on earth. The ancestor of all hominids. The ancestor of all mammals. Tiktaalik, the (possible) ancestor of all tetrapods. Earlier.

    You can't accurately count that.

    •  True. That's why I cut it off arbitrarily at th... (0+ / 0-)

      True. That's why I cut it off arbitrarily at the beginning of the Holocene. Even trying to untangle the earlier days of our genus are too overwhelmin. The real answer is unknowable but it is certainly many orders of magnitude greater.

    •  Our life goes back that long ago too. (0+ / 0-)

      In essence, we have all been alive continuously all this while.  Our life did not start at birth, just our separations from a parent did.  Life is a continuity and we have somehow survived for billions of years without interruption to arrive at this point.

  •  UGH (0+ / 0-)

    All this math makes my ears bleed.  Therefore I am probably not related to Pythagoras.  Oh well

  •  6 Billion, huh? (0+ / 0-)

    And not one of those chiselers could leave me so much as a nickel.

  •  I got like five total ancestors. Couple of them (0+ / 0-)

    were hella ancestors.

    Slow thinkers - keep right

    by Dave the Wave on Thu Aug 14, 2014 at 03:30:17 PM PDT

  •  I've been doing genealogy for 4-5 years... (1+ / 0-)
    Recommended by:
    rl en france

    ... and only one of the branches stretches back more than 7 generations, but that one branch is documented beyond belief. All together, out of that one branch, I have over 1,000 direct-line ancestors and many more cousins.

    A remotely-related cousin-removed of my mother's applied for the D. A. R. some 40 years ago, and in order to be admitted, she had to document ancestry back to the Revolutionary War period.

    She did, and it turns out our family has roots in colonial and Mayflower-era New England as well as the English aristocracy before making the crossing.

    I had always grown up believing my family was pretty much purebred Irish-Catholic, and 13 of my 16 great-great-grandparents did come over from the NW side of Ireland between 1840 and 1880.

    (My mother always said she would neither have applied for or accepted DAR membership "on a bet.")

    It was actually somewhat of a shock to find out that one stem of our lineage goes straight back to pre-colonial England  -- the very Brits we were always told were booting our Irish ancestors out.

    The thing is that records for Irish Catholics dry up abruptly about the year 1800. In those years literacy rates were very low and the occupying British government was not always interested in keeping meticulous census records in remote Irish provinces.

    The 'aristocracy' branches take us into the British royalty back in the 1400s/1500s so we have all the tenuous and remote relationships to legendary historical figures. It's fun to read and daydream about but I haven't been booking any vacations at Buckingham Palace lately.

  •  Thought experiment (0+ / 0-)

    I'll leave finding the result as an exercise for the reader.
    Suppose you start with 6 distinct family lines: Let's call them A, B, C, D, E, and F.  Each family has 3 descendants to continue the family line. To keep things simple,let's disregard M/F matching and assume each M is paired with a F and vice versa. Each descendant forms a unique pair with one of the descendants from one of the other lines. So, for example, you might have :
    Now, B, D, and F each only have 2 descendants left to pair off with any other family line but "A" and their own.
    Assuming you've done your matching ideally, you should now have 9 pairs in the second generation. Why 9? Simply, because there are 18 descendants from the first generation (6 families x 3), divided by 2.
    Now each pair in the 2nd generation has three descendants:
    A-B: AB AB AB
    A-D: AD AD AD
    A-F: AF AF AF
    This is where we can introduce variations into the experiment. Sibling pairings can be dismissed out of hand, but what about cousins? 2nd cousins? Eliminate 3rd cousin pairings, and you may find it difficult to even find suitable pairings!
    So the three AB's find pairings with other second generation:
    Can you already see where this is going? The 3rd generation (in this case):
    If we enforce unique pairs, by the third generation, our descendants are already a mix of 4 of the original 6 family lines. You can probably predict what will happen in the 4th generation: It would become impossible to pair any of the 4th generation with someone who wasn't a relation in the previous 3 generations.
    Now you can play with the rules a bit and see how that changes the results.
    You can enforce stricter pairings, for example, A's can only pair with B's, but we'd be marrying off cousins exclusively in the 3rd generation. How about "pair with the closest letter *not*a relation? Yikes!
    What about increasing/decreasing the number of children per pair?
    I think  this experiment convincingly determines that in any population, it's not long before everybody in a particular "breeding pool" is related to everybody else.

  •  I've just started genealogical work myself (0+ / 0-)

    using a great site called wikitree. It's free and easy to use.

  •  Excellent diary!! (0+ / 0-)

    Great work!!

    "For we, the people, understand that our country cannot succeed when a shrinking few do very well and a growing many barely make it." - President Barack Obama, Second Inaugural Address, January 21, 2013.

    by surfermom on Fri Aug 15, 2014 at 07:36:02 AM PDT

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