# Who's our daddy (and mommy)? Last human identical ancestors point? **URL:** \ **Category:** Factual Questions\ **Created:** [December 4, 2012, 5:20am UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936 "2012-12-04T05:20:16Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Chief\_Pedant](https://avatars.discourse-cdn.com/v4/letter/c/a6a055/32.png) [@Chief\_Pedant](https://boards.straightdope.com/u/Chief_Pedant)\ **Post date:** [December 4, 2012, 5:20am UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/1 "2012-12-04T05:20:16Z")
What’s the current dope on this from any anthropology experts here? (And for any who aren’t, please don’t bother to quote the drivel from Wikipedia unless you read the source article from Chang. As nearly as I can tell, whoever wrote the Wiiki piece had no idea of the difference between mathematical modeling and actual currently accepted historic human migration patterns.) ---
**Author:** ![njtt](https://avatars.discourse-cdn.com/v4/letter/n/ecd19e/32.png) [@njtt](https://boards.straightdope.com/u/njtt)\ **Post date:** [December 4, 2012, 9:13am UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/2 "2012-12-04T09:13:29Z")
Well, I know who my daddy and mommy were, even if you don’t know yours. 😛 I suppose your real question is meant to be something about human evolution, but I can’t make head nor tail of what it is about human evolution that you are trying to ask. Perhaps you could reword your question so as to be, you know, coherent? A link to the Wikipedia piece that you are dissatisfied with might give us a clue too. ---
**Author:** ![naita](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/naita/32/5862_2.png) [@naita](https://boards.straightdope.com/u/naita)\ **Post date:** [December 4, 2012, 11:52am UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/3 "2012-12-04T11:52:24Z")
I expect it’s this one, or one of the related ones quoting the same paper: > **[Identical ancestors point](https://en.wikipedia.org/wiki/Identical_ancestors_point)** > > In genetic genealogy, the identical ancestors point (IAP), or all common ancestors (ACA) point, or genetic isopoint, is the most recent point in a given population's past such that each individual alive at this point either has no living descendants, or is the ancestor of every individual alive in the present. This point lies further in the past than the population's most recent common ancestor (MRCA). > A set of full siblings has an IAP one generation back: their parents. Similarly, double first ... ---
**Author:** ![kopek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kopek/32/337_2.png) [@kopek](https://boards.straightdope.com/u/kopek)\ **Post date:** [December 4, 2012, 3:37pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/4 "2012-12-04T15:37:24Z")
I’m related to Megan Smolenyak-Smolenyak ------ I have heard more about this than I care to. Don’t get me wrong; I find it fascinating ------- but at a certain poijnt it becomes Ecedrin Headache #273 Current thought is Adam is 142,000 or so years back and Eve at maybe 150,000 years back or more. I know you don’t like Wiki but > **[Y-chromosomal Adam](https://en.wikipedia.org/wiki/Y-chromosomal_Adam)** > > In human genetics, the Y-chromosomal most recent common ancestor (Y-MRCA, informally known as Y-chromosomal Adam) is the patrilineal most recent common ancestor (MRCA) from whom all currently living humans are descended. He is the most recent male from whom all living humans are descended through an unbroken line of their male ancestors. The term Y-MRCA reflects the fact that the Y chromosomes of all currently living human males are directly derived from the Y chromosome of this remote ancestor. ... covers it pretty fairly. ---
**Author:** ![Loach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/loach/32/350_2.png) [@Loach](https://boards.straightdope.com/u/Loach)\ **Post date:** [December 4, 2012, 3:40pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/5 "2012-12-04T15:40:23Z")
I’m my own Grandpa. ---
**Author:** ![sweeteviljesus](https://avatars.discourse-cdn.com/v4/letter/s/898d66/32.png) [@sweeteviljesus](https://boards.straightdope.com/u/sweeteviljesus)\ **Post date:** [December 4, 2012, 4:16pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/6 "2012-12-04T16:16:45Z")
Accident with a contraceptive and a time machine? ---
**Author:** ![Darth\_Panda](https://avatars.discourse-cdn.com/v4/letter/d/ee7513/32.png) [@Darth\_Panda](https://boards.straightdope.com/u/Darth_Panda)\ **Post date:** [December 4, 2012, 4:32pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/7 "2012-12-04T16:32:30Z")
> [@Loach](#): > > I’m my own Grandpa. Well, I’m not taking any time travel advice from you. ---
**Author:** ![President\_Johnny\_Gentle](https://avatars.discourse-cdn.com/v4/letter/p/5f9b8f/32.png) [@President\_Johnny\_Gentle](https://boards.straightdope.com/u/President_Johnny_Gentle)\ **Post date:** [December 4, 2012, 4:37pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/8 "2012-12-04T16:37:45Z")
> [@Darth\_Panda](#): > > Well, I’m not taking any time travel advice from you. You can claim that, but I suspect you’ll be crawling to him when the Brainspawn attack. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [December 4, 2012, 4:43pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/9 "2012-12-04T16:43:12Z")
> [@Chief\_Pedant](#): > > What’s the current dope on this from any anthropology experts here? > > (And for any who aren’t, please don’t bother to quote the drivel from Wikipedia unless you read the source article from Chang. As nearly as I can tell, whoever wrote the Wiiki piece had no idea of the difference between mathematical modeling and actual currently accepted historic human migration patterns.) We don’t have any way of knowing this other than using modeling. We may, at some future date, have the technology to analyze everyone’s DNA (or a sufficiently large sample) and project backwards, but my understanding is that we have difficulty projecting back more than a few generations right now. And I don’t see that the modeling results in the wikipedia article are inconsistent with what we know about human migration patterns. We’ve had a half-dozen threads on this subject over the years, so you might want to search them and see what was discussed. ---
**Author:** ![naita](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/naita/32/5862_2.png) [@naita](https://boards.straightdope.com/u/naita)\ **Post date:** [December 4, 2012, 5:15pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/10 "2012-12-04T17:15:29Z")
> [@kopek](#): > > I’m related to Megan Smolenyak-Smolenyak ------ I have heard more about this than I care to. Don’t get me wrong; I find it fascinating ------- but at a certain poijnt it becomes Ecedrin Headache #273 > > Current thought is Adam is 142,000 or so years back and Eve at maybe 150,000 years back or more. I know you don’t like Wiki but > [Y-chromosomal Adam - Wikipedia](http://en.wikipedia.org/wiki/Y-chromosomal_Adam) > covers it pretty fairly. That’s covered in the article I linked to earlier: > [@](#): > > The identical ancestors point for Homo sapiens has been estimated to between 15,000 and 5,000 years ago, with an estimate of the human MRCA living about 2,000 to 5,000 years ago, that is, estimating the IAP to be about three times as distant as the MRCA.[3] Note that both the matrilineal and the patrilineal human MRCAs are far more remote still, dating to some 150,000 and 90,000 years ago, respectively. What the OP desires, I think, is a date for the last identical ancestor, which could be identical to the patrilineal, but probably isn’t, the patrilineal (and matrilineal) ancestor just has the benefit of having passed down a packet of genes that makes it possible to trace him. I’m not an anthropologist, but it seems to me as well that the 15,000 to 5,000 year estimate is a fairly uninteresting mathematical exercise with insufficient anthropological input. Don’t we have to go back to at least before the ancestors of the Aboriginal Australians arrived in Australia? ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [December 4, 2012, 5:23pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/11 "2012-12-04T17:23:44Z")
New Scientist recently had a cover article (Our true dawn: Pinning down human origins, 26 November 2012 by Catherine Brahic; only available to subscribers) about recent research that showed that humans average fewer mutations in the DNA per generation than previously thought. Therefore, divergences in the past took place longer ago geneticists believed. > [@](#): > > Quibbles aside, it now seems certain that our lineage is considerably older than we once thought. And that has consequences for the rest of human prehistory. The molecular clock has been used to date a number of key events, not least when our ancestors left Africa. That has been estimated by looking at genetic differences between the Yoruba people of Nigeria and Europeans and Asians. > > Early genetic estimates suggested this happened 50,000 years ago. So when fossil remains in Israel and archaeological sites in India were found to be around 100,000 years old, there was some explaining to do. The Israeli bones were dismissed as the remains of an early, dead-end excursion, and the Indian sites as an error, pure and simple. The new molecular clock resolves the discrepancy, pushing the departure back to between 90,000 and 130,000 years ago. That would give a ballpark, depending on what the OP is asking for. ---
**Author:** ![Loach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/loach/32/350_2.png) [@Loach](https://boards.straightdope.com/u/Loach)\ **Post date:** [December 4, 2012, 5:34pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/12 "2012-12-04T17:34:43Z")
> [@sweeteviljesus](#): > > Accident with a contraceptive and a time machine? https://www.youtube.com/embed/7AvG6q_iTcA?feature=oembed&wmode=opaque ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [December 4, 2012, 5:46pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/13 "2012-12-04T17:46:20Z")
> [@naita](#): > > That’s covered in the article I linked to earlier: > > What the OP desires, I think, is a date for the last identical ancestor, which could be identical to the patrilineal, but probably isn’t, the patrilineal (and matrilineal) ancestor just has the benefit of having passed down a packet of genes that makes it possible to trace him. > > I’m not an anthropologist, but it seems to me as well that the 15,000 to 5,000 year estimate is a fairly uninteresting mathematical exercise with insufficient anthropological input. Don’t we have to go back to at least before the ancestors of the Aboriginal Australians arrived in Australia? No, we don’t. It’s unlikely that any surviving Australian does not have at least one non-Australian ancestor, even if he doesn’t know it. Before the so-called Age of Discovery, things might have been different. But that was 500 years ago and there’s been a lot of hanky-panky going on in the ensuing years! The OP is looking for actual genetic data for the identical ancestor. Such data simply doesn’t exist, and is not likely to exist for some time to come, if ever. ---
**Author:** ![April\_R](https://avatars.discourse-cdn.com/v4/letter/a/3da27b/32.png) [@April\_R](https://boards.straightdope.com/u/April_R)\ **Post date:** [December 4, 2012, 5:50pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/14 "2012-12-04T17:50:56Z")
I’ll ask my evolutionary Anthro teacher and get back to you. ---
**Author:** ![Chief\_Pedant](https://avatars.discourse-cdn.com/v4/letter/c/a6a055/32.png) [@Chief\_Pedant](https://boards.straightdope.com/u/Chief_Pedant)\ **Post date:** [December 4, 2012, 6:21pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/15 "2012-12-04T18:21:22Z")
> [@John\_Mace](#): > > We don’t have any way of knowing this other than using modeling. We may, at some future date, have the technology to analyze everyone’s DNA (or a sufficiently large sample) and project backwards, but my understanding is that we have difficulty projecting back more than a few generations right now. > > And I don’t see that the modeling results in the wikipedia article are inconsistent with what we know about human migration patterns. We’ve had a half-dozen threads on this subject over the years, so you might want to search them and see what was discussed. Let me clarify a couple of things. The “last identical ancestors point” is an actual concept, not a term I invented. While it’s similar to the most recent common ancestor, it’s more specific. Mathematical modeling such as done by Chang (and referenced several places in Wikipedia) yields a nonsensical result of “5-15K years.” This is beyond stupid. It’s impossible. We start out in Africa 200K years ago, and move out (the population that moved out for good) about 75K years ago. Svante Paabo thinks one tiny portion of the population that moved out and ended up being Out of Africa Eve to the Eurasian population interbred with Neanderthals. Neanderthal ancestors in turn Africa quite a bit earlier. If we ignore the Neanderthal part of the Eurasian gene pool, our last identical ancestors point would be somewhere over 75K years ago, but perhaps quite a bit longer depending on the time of separation of the sub saharan populations who stayed in Africa. If we accept the Neanderthal interbreeding theory, then would not the identical ancestors point get pushed back over 500,000 years for the identical ancestors point for Eurasians (Neanderthal-mix sub-portion of human populations) versus sub-saharans? This is the thing I’m trying to get at. There is such a stark contrast between a mathematical modeling that assumes “random mating” and gets a number of 5-15K years, and an analysis of historic migration patterns that establishes a minimum of 100K plus years for the last human identical ancestors point–with an upper bound of 500K+ years. The various undereducated replies listed above are not helpful. They are, in my view, a reflection of a distressing trend back toward a simplistic creationist history of mankind but have little in common with fact. I’m wondering if anyone on the board wants to advance fact. Exapno is closer to the kind of reply I find helpful. ETA: My comment about Wikipedia was simply to let posters know I’m not interested in hearing a parroting of bad information. If you have some insight on the topic, I’d like to hear it. If not, I don’t need to be told to read Wikipedia. ---
**Author:** ![April\_R](https://avatars.discourse-cdn.com/v4/letter/a/3da27b/32.png) [@April\_R](https://boards.straightdope.com/u/April_R)\ **Post date:** [December 4, 2012, 6:54pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/16 "2012-12-04T18:54:58Z")
This is from my professor: > [@](#): > > In a general sense, all modern humans last lived together in a single society 65,000 years ago. Genetically, we all share an individual female ancestor (“Eve”) 100,000-200,000 years ago, she gave all of us our mitochoindria. All men share a common male ancestor (“Adam”) about 70,000 years ago, who gave men their Y chromosome. Hope that helps. ---
**Author:** ![septimus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/septimus/32/410_2.png) [@septimus](https://boards.straightdope.com/u/septimus)\ **Post date:** [December 4, 2012, 7:07pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/17 "2012-12-04T19:07:47Z")
The claim in Wikipedia actually comes from [a pdf paper by Douglas Rohde, a well-credentialed PhD](http://tedlab.mit.edu/~dr/Papers/Rohde-MRCA-two.pdf), who, I think, bases his claims on somewhat elaborate simulations using real-world topology. The claim implies that the identical ancestors of aboriginal Australians all had descendacy paths which migrated away from Australia after 13,000 BC to become ancestral to _all living humans_. This may strike us intuitively as unlikely, but it seems to be the result found by Rohde. The claim depends on parameters, e.g. the leakage from Australia (prehistoric people who accidentally rafted away to New Guinea), which is explicitly shown on page 14 of the paper. Rohde discusses some inter-continental migrations, but I see no mention of Australia and have no idea how he guesstimated that parameter. Small changes in the parameters can have a big effect on results like Identical Ancestor Point. The real numbers may be unknowable and likely to be more conservative than those found with the model – I suspect Rohde would agree with that. ---
**Author:** ![Freddy\_the\_Pig](https://avatars.discourse-cdn.com/v4/letter/f/a587f6/32.png) [@Freddy\_the\_Pig](https://boards.straightdope.com/u/Freddy_the_Pig)\ **Post date:** [December 4, 2012, 8:15pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/18 "2012-12-04T20:15:06Z")
I don’t understand how this: > [@Chief Pedant](#): > > If we ignore the Neanderthal part of the Eurasian gene pool, our last identical ancestors point would be somewhere over 75K years ago, but perhaps quite a bit longer depending on the time of separation of the sub saharan populations who stayed in Africa. . . . follows from this: > [@Chief Pedant](#): > > We start out in Africa 200K years ago, and move out (the population that moved out for good) about 75K years ago. Just because humans moved out of Africa doesn’t mean that a wall of separation came down around the continent. There was always leakage across the Sinai and around the coasts. Granted, for most of human history people who lived in China weren’t mating with people who lived in South Africa. But Chinese mated with central Asians who mated with Arabians who mated with north Africans who mated with central Africans who mated with south Africans. Over hundreds of generations a Chinese could easily become ancestral to an African, or even to every African. Or the reverse. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [December 4, 2012, 11:39pm UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/19 "2012-12-04T23:39:56Z")
> [@Chief\_Pedant](#): > > Let me clarify a couple of things. > The “last identical ancestors point” is an actual concept, not a term I invented. I know what it is, and it was linked to early in this thread. > [@](#): > > While it’s similar to the most recent common ancestor, it’s more specific. > Mathematical modeling such as done by Chang (and referenced several places in Wikipedia) yields a nonsensical result of “5-15K years.” This is beyond stupid. It’s impossible. No, it’s not. I believe this work was done before the Neanderthal genetic data was known, and if we do ignore it, there is no reason that the identical ancestor point has to be \> 75k years ago. Where are you getting that from? ---
**Author:** ![Chief\_Pedant](https://avatars.discourse-cdn.com/v4/letter/c/a6a055/32.png) [@Chief\_Pedant](https://boards.straightdope.com/u/Chief_Pedant)\ **Post date:** [December 5, 2012, 12:03am UTC](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936/20 "2012-12-05T00:03:26Z")
> [@April\_R](#): > > This is from my professor: Your professor needs to do a little more research. [Next page](https://boards.straightdope.com/t/whos-our-daddy-and-mommy-last-human-identical-ancestors-point/642936.md?page=2)