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  #51  
Old 09-25-2012, 11:15 AM
FuzzyOgre FuzzyOgre is offline
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Another one from real life:

My grand mother married my grand father(no duh!). Somewhere around the same time, her sister married my grandfathers brother(neither set are twins). So my dad has, in effect, a bunch of double first cousins. This is an example of ancestor collapse without any cousin kissing.

Double familial weddings like that were probably not uncommon in the past.

What is interesting is that both marriages produced large families, twelve kids each. They grew up feeling a special bond.
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  #52  
Old 09-25-2012, 01:28 PM
md2000 md2000 is offline
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The problem is complex with european exploration, but the real question - difficult to answer - is how often people went far afield to reproduce. The math for Australia works great if it is a numberline or a road, but in a 2-dimesional map that process can take a while. Then there's the hard-to-navigate geographical barriers, like Tasmania, Tierra del Fuego, the gap between Panama and Columbia, Newfoundland, etc. These barriers are a lot easier for the original inhabitants to cross, there were no hostile locals defending their territory on the other side.

If a common ancestry has to do an end run around a desert or mountain range, it will take a lot longer than going straight across.

In a tribal village of say, 50 individuals, aboriginal, Indian, what have you - how long before everyone, or even half the population, are related to the stranger who came into their group many moons ago? Lets' say it's distributed 10-20-20. That is, 10 of the oldest generation, 20 of aprents, 20 of children. Running Mouth joins the tribe, or Happy Hips gets knocked up in the bush. A generation later, there's 2 children. they marry, 2 generations later there's 4 related offspring, So 3 or 4 generations later everyone can claim ancestry, provided not too many newbies join the group or not too many women are traded to the next tribe. Double the social group and the "leavening" takes longer, the only saving grace may be that more strangers are coming in.
  #53  
Old 09-25-2012, 01:38 PM
jbaker jbaker is offline
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Originally Posted by Blake View Post
The problem with that argument is that it makes the alternative even more likely. If "fat tails" make a recent ancestor unlikely, it makes the presence of individuals with no common ancestors even more likely, simply because there are 6 billion ways to find a common ancestor, and only one way to avoid doing so.
I don't follow you. There will always be common ancestors. The only question is how far we have to go back to find the most recent common ancestor.


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Originally Posted by Blake View Post
No people of New Guinea are isolated, radically or otherwise. Some of the agriculturalists were isolated from other agriculturalists, but they all maintained contact and interbred with adjacent HGs.
New Guinea has a challenging terrain that led to extreme isolation. The Dani people of the Grand Valley in west New Guinea believed that they were the only people in the world until they were discovered from the air in 1938. The interior of east New Guinea similarly was thought to be empty until prospectors discovered it was populated in 1930.


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Originally Posted by Blake View Post
The uncontacted tribes of South America are all village farmers and all are in contact with their neighbours, or were until 50 years ago. More importantly, they all seem to be descendants of the great agricultural kingdoms that were decimated from European disease. They aren't people who have always lived like that, they are people whose ancestors just 500 years ago lived in cities under hereditary kings. There seems to be no way that they could be isolated.
Yes, of course the ancestors of the uncontacted tribes of South America were integrated members of the pre-Columbian civilizations. After those civilizations collapsed, however, they retreated into the rain forests and avoided contact with Europeans. It seems likely that at least some of them have no European ancestry (though most, of course, do).


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Originally Posted by Blake View Post
Do you have a reference for this claim? It would be interesting to see how anyone would establish such a fact, given that the Hawaiians had no written language. If an Hawaiian had a Tahitian ancestor born in 1066, how would they ever know? No English commoner could prove that they had no single French ancestor from 1066, and that is a literate culture with some of the world's best written records. I can't see how an Hawaiian could ever be certain that they had no Tahitian ancestry from the same date.

And that is the reason why Hawaiians can't be described as being in any way isolated. We know they weren't radically isolated, to the extent that Hawaiian is mutually intelligible with other Polynesian languages. From both linguistic and archaeological evidence we can be sure that Hawaiians were in constant cohabitation, not just occasional contact, with the outside world until just 800 years ago. It seems likely that the last common ancestor of Hawaiians and other Polynesians is less than 1, 500 years back. That would makes the Hawaiians less isolated than Europeans.
I don't mean that the Hawaiians are autochthonous, with no relationship to other humans in the world. Rather, I mean that there are Hawaiians all of whose ancestors are Hawaiian, to a point prior to the discovery of Hawaii by Captain Cook. There are several thousand purebred Hawaiians, and records are quite good for most of the intervening period. Of course, if you go back far enough then the Hawaiians came from elsewhere in Polynesia, and there also has been at least some contact historically between Hawaiians and other Polynesians.

My point in all this is not to preclude the possibility of contacts, but to argue that, for at least some people, it would have taken a long time to establish descent from the MRCA. For example, suppose that I am right that there are native Americans in South America with no post-Columbian European or African ancestors. How then would there be descent? Well, the Bering Strait is a somewhat porous barrier, so we don't have to go back to the original settlement of the Americas. But it takes time for a person at the Bering Strait to have a descendant in South America.
  #54  
Old 09-25-2012, 11:52 PM
foolsguinea foolsguinea is offline
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What bothers me about the way Blake is framing things is that he seems to think that if present-day Eurasia has a MRCA, say, 3000 years ago (which is not necessarily the case, btw) and there was any intermingling between Eurasians and other populations in the last 3000 years, then of course everyone has that same MRCA. And it doesn't work that way. Intermingling of non-Sentinelese with Sentinelese (substitute Amerind, New Guinean, Khoi, whatever) could have happened in the last several centuries, but before the intermarriage that creates an "Eurasian MRCA 3000 years ago."

And of course there's not an inevitable, consistent rate of intermarriage or pedigree collapse. So despite what some people think, even a Eurasian MRCA is thousands not hundreds of years ago.

Last edited by foolsguinea; 09-25-2012 at 11:54 PM.
  #55  
Old 09-26-2012, 09:56 PM
robby robby is offline
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Originally Posted by jbaker View Post
...Yes, of course the ancestors of the uncontacted tribes of South America were integrated members of the pre-Columbian civilizations. After those civilizations collapsed, however, they retreated into the rain forests and avoided contact with Europeans. It seems likely that at least some of them have no European ancestry (though most, of course, do).
What you seem to be missing is the fact that none of these remote tribes needed to have contact with Europeans in order for them to ALL have European ancestry.

How to explain this paradox?

This is because they didn't need to ever come in contact with a European. All that is necessary is for someone in the village to intermarry with someone from the next tribe over, who themselves is the descendent of an intermarriage between a Native American and a European. Feel free to add as many intermediate steps in the middle as you like.

In addition, with the small size of the typical tribe, it does not take long before everyone in the village ends up with European ancestry as well.

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Originally Posted by jbaker View Post
...For example, suppose that I am right that there are native Americans in South America with no post-Columbian European or African ancestors. How then would there be descent?
You are almost certainly not right.
  #56  
Old 09-26-2012, 10:34 PM
Chessic Sense Chessic Sense is offline
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Originally Posted by Chronos View Post
Nitpick: You mean the female-line MRCA and male-line. Everyone's father's father's father's ... father was Y-Adam, and so he was most certainly a common ancestor of all humanity, but his mother was also, therefore, a common ancestor of all humanity. And the mixed-line MRCA was much more recent than either Y-Adam or Mitochondrial Eve.
I don't understand what you're nitpicking. We said most recent common ancestor. So if Y-Adam has a daughter and several sons, that daughter would replace her grandmother as the most recent ancestor of everyone. And if that daughter bore all of humanity to more than one of Y-Adam's sons, then he can't ever be stripped of his "Y-Adam" title, presuming no more bottlenecks happen (an apocalyptic flood, perhaps).

Now either presume that the line is more complicated or even that Y-Adam never met his daughter. Then we'd have the case, as I said, that MRCA-male never knew MRCA-female. Sure, Y-Adam knew his mom, but that doesn't mean she's the most recent.

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Originally Posted by Blake View Post


I can't make sense of this...

I'm guessing I'm missing something here.

Perhaps you are working form a position that "step sibling" or adopted sibling or other relationships that have no objective or genetic basis are sufficient to establish a relation chain. But I don't think that's what the OP wants.
No, I just screwed up my example. I thought of the correct version in the shower and was loth to bring my laptop in there with me, but Aspidistra got to it before me:

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Originally Posted by Aspidistra View Post
His point is valid, even though the example given may not work exactly. The simplest example of it that I can devise involves 15 people:

Now Generations 1 and 2 die. Everyone left (Mark, Nick and Olivia) is a first cousin to any other person, even though the MRCA is more than 2 generations back.
Yeah, that. Essentially, 3 couples live in houses in a cul-de-sac. They each have a boy and a girl and superfluous children we don't care about. The eldest son marries the eldest daughter of the house to the right of his (and therefore the daughters marry left). They all have kids. Those kids, no matter how many there are, are all first cousins or siblings. Yet no single ancestor can be pointed to as having sired/borne everyone.

Extended, unproven theory: With X couples, you need X generations (inclusively) to create the same phenomenon. So with 4 couples, everyone can find a common great-grandparent.

Last edited by Chessic Sense; 09-26-2012 at 10:37 PM.
  #57  
Old 09-27-2012, 12:08 AM
John Mace John Mace is offline
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Originally Posted by foolsguinea View Post
What bothers me about the way Blake is framing things is that he seems to think that if present-day Eurasia has a MRCA, say, 3000 years ago (which is not necessarily the case, btw) and there was any intermingling between Eurasians and other populations in the last 3000 years, then of course everyone has that same MRCA. And it doesn't work that way. Intermingling of non-Sentinelese with Sentinelese (substitute Amerind, New Guinean, Khoi, whatever) could have happened in the last several centuries, but before the intermarriage that creates an "Eurasian MRCA 3000 years ago."

And of course there's not an inevitable, consistent rate of intermarriage or pedigree collapse. So despite what some people think, even a Eurasian MRCA is thousands not hundreds of years ago.
Well, Blake is reflecting the results of the peer reviewed scientific journals on the subject. If you have better data, perhaps you should publish an article and debunk that data.

Last edited by John Mace; 09-27-2012 at 12:08 AM.
  #58  
Old 09-27-2012, 05:12 PM
Chronos Chronos is offline
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Quote:
Quoth Chessic Sense:

I don't understand what you're nitpicking. We said most recent common ancestor. So if Y-Adam has a daughter and several sons, that daughter would replace her grandmother as the most recent ancestor of everyone. And if that daughter bore all of humanity to more than one of Y-Adam's sons, then he can't ever be stripped of his "Y-Adam" title, presuming no more bottlenecks happen (an apocalyptic flood, perhaps).
The most recent common ancestor was far more recent than either Y-Adam or Mitochondrial Eve. And if we're going to specify "most recent common male ancestor" and "most recent common female ancestor", the odds are overwhelming that the two of them were either married, or a parent-child pair.

Think of it this way: There's a most recent common ancestor. That person is either male or female; let's say without loss of generality that he was male. Well, if he was monogamous, then his wife is also a most recent common ancestor. And even if he wasn't monogamous, then his mother would also be a common ancestor, and therefore the most recent common female ancestor can't possibly be any earlier than one generation before him. So for the most recent common female ancestor to be anyone other than the mother of the most recent common male ancestor, you'd need to find a different rout of ancestry to someone else, within a single generation of the route you found to the first guy.
  #59  
Old 09-28-2012, 07:30 AM
hibernicus hibernicus is offline
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Originally Posted by Chessic Sense View Post
So if Y-Adam has a daughter and several sons, that daughter would replace her grandmother as the most recent ancestor of everyone. And if that daughter bore all of humanity to more than one of Y-Adam's sons
This looks like a misunderstanding of the concept of "Y-Adam". At the time Y-Adam lived (whenever that was), there were lots of other people around, both male and female. So he didn't necessarily have a daughter, and if he did she did not have to mate with her brothers, nor did she become an ancestor of all of humanity.

In fact, the names "Y-Adam" and "mitochondrial Eve" are probably more confusing than they are worth, because of course they make people think of the Biblical Adam and Eve.
  #60  
Old 09-28-2012, 11:08 AM
BigT BigT is online now
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Originally Posted by John Mace View Post
Well, Blake is reflecting the results of the peer reviewed scientific journals on the subject. If you have better data, perhaps you should publish an article and debunk that data.
No. That is not how reasoning works. Blake has to provide the reasoning why foolsguinea's argument is invalid, seeing as an obvious example of the logic being flawed was given. Magazines reference peer researched journals all the time and get things horribly wrong. It's not some magic wand that makes you correct.

And if you want to claim that there are peer reviewed journals that agree with you, then it's on you to provide the citations. Your claim is essentially meaningless.
  #61  
Old 09-28-2012, 10:19 PM
Chessic Sense Chessic Sense is offline
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Originally Posted by Chronos View Post
The most recent common ancestor was far more recent than either Y-Adam or Mitochondrial Eve. And if we're going to specify "most recent common male ancestor" and "most recent common female ancestor", the odds are overwhelming that the two of them were either married, or a parent-child pair.

Think of it this way: There's a most recent common ancestor. That person is either male or female; let's say without loss of generality that he was male. Well, if he was monogamous, then his wife is also a most recent common ancestor. And even if he wasn't monogamous, then his mother would also be a common ancestor, and therefore the most recent common female ancestor can't possibly be any earlier than one generation before him. So for the most recent common female ancestor to be anyone other than the mother of the most recent common male ancestor, you'd need to find a different rout of ancestry to someone else, within a single generation of the route you found to the first guy.
I don't understand what we're fighting about, here. Let's do a quick recap:

OP: Are we all 50th cousins or less?
Someone: Well the MRCA was more than 50 generations ago, so no.
Me: MRCA is irrelevant. We can prove a population to all be small-number cousins without needing to know where there is an MRCA, if any at all.
You: Unclear nitpick. Y-Adam this and that.
Me: I don't understand. Are you saying they knew each other? Not necessarily.

So help a brother out here. Explain exactly what you're nitpicking. If the male MRCA had a daughter that he never met, then my assertion stands. How am I wrong?

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Originally Posted by hibernicus View Post
This looks like a misunderstanding of the concept of "Y-Adam". At the time Y-Adam lived (whenever that was), there were lots of other people around, both male and female. So he didn't necessarily have a daughter, and if he did she did not have to mate with her brothers, nor did she become an ancestor of all of humanity.

In fact, the names "Y-Adam" and "mitochondrial Eve" are probably more confusing than they are worth, because of course they make people think of the Biblical Adam and Eve.
I'm using Y-Adam to mean the most recent male common ancestor, as Chronos was above. Let's say Jimmy sired a son, who had a son, who had a son, who had Bob, who fathered all of (today's) humanity. Who are you calling Y-Adam, Jimmy or Bob? I'm saying it's Bob.

Second, I know he didn't necessarily have a daughter, but he could have, which he never had to meet. And if she had kids with another family's male, and their descendants are alive today, then her dad can't be Y-Adam/maleMRCA...that other guy's Y would spoil his claim. Now if those other kids died out and only the incestual kids survived to today, then that's a different story.
  #62  
Old 09-29-2012, 03:27 AM
septimus septimus is online now
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Originally Posted by Chessic Sense View Post
I'm using Y-Adam to mean the most recent male common ancestor, as Chronos was above.
That's not how Chronos was using the term; nor is it the standard way.

Y-chromosome Adam (or simply Y-Adam) is the (most recent) man who donated his Y-chromosome to all now-living men. Note that being an ancestor, and being the Y-chromosome ancestor (aka patrilineal ancestor, aka agnatic ancestor) are quite different. Charlemagne, for example, has at least a billion living descendants, yet, as far as is known, not a single agnatic descendant.

The Y-chromosome is passed father-to-son with little change. You have (ignoring duplications) 2 million 20-great grandfathers, but only one of them is your unique agnatic (Y-chromosome) 20-great grandfather.

(With DNA testing falling in price, a tree structure connecting all the men of the world is becoming visible, providing fascinating insights into prehistory.)
  #63  
Old 09-29-2012, 09:48 AM
Chronos Chronos is offline
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Second, I know he didn't necessarily have a daughter, but he could have, which he never had to meet. And if she had kids with another family's male, and their descendants are alive today, then her dad can't be Y-Adam/maleMRCA...that other guy's Y would spoil his claim. Now if those other kids died out and only the incestual kids survived to today, then that's a different story.
Not necessarily. His mother was certainly a common ancestor to everyone, but his daughter need not be. The most recent common ancestor certainly had more than one child, and may well have had more than two. He could, for instance, have had three sons whose lines all spread prolifically, and one daughter whose line spread much more slowly, or possibly even died out after some number of generations.
  #64  
Old 03-04-2016, 04:08 PM
JessicaHoyt JessicaHoyt is offline
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I could imagine this could be true for people of "Old World" ancestry. However, I assume that there are still plenty of full blooded Native Americans or Australian Aborgines. In the United States Native Anericans were not really allowed to interact with the rest of the population until 1924 when they gained citizenship. Therefore a 92+ year old American Indian really can't have Old World ancestry unless one of their parents illegally left the reservation, and even a Native American born in 2016 would likely have only 16 ancestors who were born after 1924. Of course Native Americans had absolutely no interaction with Old World people until 1492, and until around 1600 the colonies were largely unpopulated. I'm not sure that 520 years since Columbus is a long enough time to give all Natives some old world blood, especially since they weren't citizens less than a century ago and most people marry in their race.
  #65  
Old 03-04-2016, 04:38 PM
Colibri Colibri is offline
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Originally Posted by JessicaHoyt View Post
I could imagine this could be true for people of "Old World" ancestry. However, I assume that there are still plenty of full blooded Native Americans or Australian Aborgines. In the United States Native Anericans were not really allowed to interact with the rest of the population until 1924 when they gained citizenship. Therefore a 92+ year old American Indian really can't have Old World ancestry unless one of their parents illegally left the reservation, and even a Native American born in 2016 would likely have only 16 ancestors who were born after 1924.
You drastically overestimate the isolation and lack of mixing of indigenous populations after 1492. The vast majority of Native Americans interacted a great deal with others long before 1924. There were Spanish settlements in Florida and the Southwest in the 1500s, and French and British fur trappers penetrated into remote areas of the continent - and took native wives - from very early times. Even on reservations, people came and went, and mixed race people would have lived there. Even people regarded as "full-blooded" Native Americans almost certainly have some European ancestors.

Last edited by Colibri; 03-04-2016 at 04:39 PM.
  #66  
Old 03-04-2016, 04:41 PM
JessicaHoyt JessicaHoyt is offline
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Originally Posted by Colibri View Post
You drastically overestimate the isolation and lack of mixing of indigenous populations after 1492. The vast majority of Native Americans interacted a great deal with others long before 1924. There were Spanish settlements in Florida and the Southwest in the 1500s, and French and British fur trappers penetrated into remote areas of the continent - and took native wives - from very early times. Even on reservations, people came and went, and mixed race people would have lived there. Even people regarded as "full-blooded" Native Americans almost certainly have some European ancestors.
There probably aren't many full blooded Natives, but exactly zero?
  #67  
Old 03-04-2016, 04:42 PM
Blake Blake is offline
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Originally Posted by JessicaHoyt View Post
I could imagine this could be true for people of "Old World" ancestry.
You do realise this thread is over 4 years old, right?

Quote:
However, I assume that there are still plenty of full blooded Native Americans or Australian Aborgines.
Some time in that 4 years you could have read the other posts. it's not like the thread is that long. To summarise: no, there are no full blooded Native Americans or Australian Aborigines.


Quote:
In the United States Native Anericans were not really allowed to interact with the rest of the population until 1924 when they gained citizenship.
Have you ever heard of Pocahontas? You know, that Indian that all those New England blue bloods claim descent from? Have you ever seen "Dances with Wolves"? "The Revenant"? Where in the world did you get this idea that Native Americans were not allowed to interact with the rest of the population until 1924? Native Americans have been fucking Europeans literally since the day of first contact in 1492 and it has been happening every single day since.

Quote:
Therefore a 92+ year old American Indian really can't have Old World ancestry unless one of their parents illegally left the reservation...
If you really believe this, then can you explain why those reservations were all formed with rules defining how much non-Indian ancestry a person was allowed to have and still live there? Why were such rules necessary if no Indians had any non-Indian ancestry?


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Of course Native Americans had absolutely no interaction with Old World people until 1492...
Umm, no. Polynesians Vikings and Siberians were all making contact with the New World well before 1492.

Quote:
....most people marry in their race.


1) No, that's not true. Most people of the upper social race tend to marry their race. Most people of the lower races tend to prefer to marry upwards, out of their race.

2) People can make babies without being married, so marriage is irrelevant. Blacks marrying whites was illegal in the South for many years, and yet astonishingly tens of thousands of babies described as being biracial were born each year. Makes you think that tens of thousands of White men were fucking Black women who they weren't married to, doesn't it?
  #68  
Old 03-04-2016, 04:48 PM
Colibri Colibri is offline
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Originally Posted by JessicaHoyt View Post
There probably aren't many full blooded Natives, but exactly zero?
I would be very surprised if there were any Native Americans in the United States with no European ancestry. It's very very unlikely after 500 years.

Recall that everyone has four grandparents, eight grandparents, etc. Going back over 500 years, everyone has over one million ancestors - including Native Americans. The odds that at least one of those ancestors was European are very large.
  #69  
Old 03-04-2016, 06:23 PM
Shagnasty Shagnasty is offline
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Originally Posted by Colibri View Post
I would be very surprised if there were any Native Americans in the United States with no European ancestry. It's very very unlikely after 500 years.

Recall that everyone has four grandparents, eight grandparents, etc. Going back over 500 years, everyone has over one million ancestors - including Native Americans. The odds that at least one of those ancestors was European are very large.
What about some isolated populations though? Remember, we aren't talking about the typical, it is about the extremes no matter how rare they are. There are still some very remote tribes in the Amazon, New Guinea, North Sentinel Island and a few other remote places that still haven't been contacted much let alone interbred with outsiders to any known degree.

Are there any pure Australian Aborigines still left? I presume there are but I really don't know. If so, they could have been genealogically for tens of thousands of years at least. Compare an extreme example from that population with someone from another isolated tribe especially in South America that has also been isolated for thousands of years and you may be able to beat the 50th cousin claim.

Last edited by Shagnasty; 03-04-2016 at 06:24 PM.
  #70  
Old 03-04-2016, 07:15 PM
Shagnasty Shagnasty is offline
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Wikipedia has a list of uncontacted tribes and populations. The most isolated people on Earth are supposedly on North Sentinel Island in the Indian Ocean under the jurisdiction of India but the Indian government made a three mile exclusion zone around the island because it is too dangerous for anyone to go there.

Only a few people have ever encountered the population that lives there in person and lived to tell about about because they are extremely murderous to anyone that is unfortunate enough to land on their island. What little is known is that they have their own language like no other known language and they may have been isolated as a small population for up to 60,000 years. They use mainly stone-age technology combined with improvising with whatever other materials wash up on their beaches. They are not even known to have firemaking technology.

If the Sentinelese really have been isolated even for a fraction of the claimed time, you could probably find an isolated population in the Amazon that has a relationship greater than 50th cousins.

Last edited by Shagnasty; 03-04-2016 at 07:18 PM.
  #71  
Old 03-04-2016, 08:20 PM
Colibri Colibri is offline
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Originally Posted by Shagnasty View Post
There are still some very remote tribes in the Amazon, New Guinea, North Sentinel Island and a few other remote places that still haven't been contacted much let alone interbred with outsiders to any known degree.
For tribes in Amazonia and New Guinea, what do you mean by "outsiders"? Even what are referred to as "uncontacted" tribes in Amazonia are almost always in contact with related groups which are in contact with Western culture. If these small tribes had been interbreeding solely within their own group for the last 20 generations they would be incredibly inbred by now. They are probably intermarriages with neighboring groups every generation, and the neighboring groups are intermarrying with groups in contact with - and interbreeding with - people with some European or African ancestry.

Remember we are talking about long stretches of time here. As I mentioned, after 20 generations everyone has a million ancestors. (Of course, in isolated groups, most of these will be the same.) The odds are that sometime in the past 500 years somebody - or many somebodies - entered the tribal lineage that had outside ancestry.

The one group I might be able to believe was possibly truly isolated is the North Sentinelese. But even these might not have been totally isolated from other people in the Andamans for the past five centuries. And the other Andamese have been in contact with outsiders.
  #72  
Old 03-04-2016, 08:42 PM
Colibri Colibri is offline
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Originally Posted by Shagnasty View Post
Wikipedia has a list of uncontacted tribes and populations. The most isolated people on Earth are supposedly on North Sentinel Island in the Indian Ocean under the jurisdiction of India but the Indian government made a three mile exclusion zone around the island because it is too dangerous for anyone to go there.

Only a few people have ever encountered the population that lives there in person and lived to tell about about because they are extremely murderous to anyone that is unfortunate enough to land on their island. What little is known is that they have their own language like no other known language and they may have been isolated as a small population for up to 60,000 years. They use mainly stone-age technology combined with improvising with whatever other materials wash up on their beaches. They are not even known to have firemaking technology.

If the Sentinelese really have been isolated even for a fraction of the claimed time, you could probably find an isolated population in the Amazon that has a relationship greater than 50th cousins.
Actually, have a look at Blake's post #34 which counters this.
  #73  
Old 03-04-2016, 08:51 PM
Shagnasty Shagnasty is offline
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Originally Posted by Colibri View Post
The one group I might be able to believe was possibly truly isolated is the North Sentinelese. But even these might not have been totally isolated from other people in the Andamans for the past five centuries. And the other Andamese have been in contact with outsiders.
I understand and you make good points. However, the claim is that EVERY single human is at least a 50th cousin to each other. All it takes is a single case to disprove that so the burden of evidence is on the people making that claim. I completely understand it as a typical statement but not as an absolute claim. You can get some strange anomalies when you compare extremely disparate populations. If the North Sentinelese really are as isolated as most anthropologists think they are, they are greater than 50th cousins to almost everyone else in the world. If they had influence from other related groups, they aren't demonstrating it because their language is not mutually intelligible to the closet islanders or any other in the world for that matter.

It is hard to believe that is possible in the 21st century but they aren't faking it as far as anyone knows. They use stone-age weapons, they don't use fire and they don't have clothing. It is difficult for anyone to even photograph them from the most sophisticated surveillance aircraft because they stay hidden under the dense foliage most of the time but they will attack with spears and bows and arrows if anyone lands on their beaches or tries to fly over at low altitude.

Again, I believe the math works for the claim in general but maybe not in the absolute sense. There are still some really odd anomalies out there that probably defy it.

Last edited by Shagnasty; 03-04-2016 at 08:56 PM.
  #74  
Old 03-04-2016, 09:17 PM
Colibri Colibri is offline
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Originally Posted by Shagnasty View Post
However, the claim is that EVERY single human is at least a 50th cousin to each other. All it takes is a single case to disprove that so the burden of evidence is on the people making that claim.
It's of course impossible to test this definitively. However, it's a matter of probabilities. In my opinion, there is a very high probability that everyone, including the North Sentinelese, are related within the past 50 generations.
  #75  
Old 03-04-2016, 10:00 PM
Blake Blake is offline
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Originally Posted by Shagnasty View Post
I understand and you make good points. However, the claim is that EVERY single human is at least a 50th cousin to each other. All it takes is a single case to disprove that so the burden of evidence is on the people making that claim.
Well, no. There is no particular burden of evidence here. Historians claim that the Tudor monarchs were descended from William the Conqueror. EVERY single Tudor monarch. All it takes is a single case to disprove that. Nonetheless the burden of proof isn't on historians making the claim.

In the real world, we accept things based on a preponderance of evidence, not on absolute certainty. Maybe Queen Elizabeth was the bastard child of a wandering Chinese minstrel. But we don't accept that, we accept what the preponderance of evidence indicates is true.


Quote:
If the North Sentinelese really are as isolated as most anthropologists think they are...
Did you read my earlier posts? They weren't very isolated at all 300 years ago, they were living amongst their neighbours.


Quote:
If they had influence from other related groups, they aren't demonstrating it because their language is not mutually intelligible to the closet islanders or any other in the world for that matter.
French is not mutually intelligible with Italian or any other in the world. Nonethless they were the exact same language just 2000 years ago. Mutual intelligibility tells us that languages are closely related. A lack of mutual intelligibility tells us exactly nothing.

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they don't use fire...
All humans use fire. You are actually claiming that they are not human?
Of course they use fire, just like all other humans. Not only do they use fire, they have some rather sophisticated methods of controlling fire, including lamps and torches.


Quote:
....and they don't have clothing.

Can we have a cite for this claim? Not a lot is known about Sentinelese fashion, but they appear to wear clothes to me. After your fire comment, I'm not prpeared to take your word on other claims.

Last edited by Blake; 03-04-2016 at 10:02 PM.
  #76  
Old 03-04-2016, 10:42 PM
AK84 AK84 is offline
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Originally Posted by Colibri View Post
The one group I might be able to believe was possibly truly isolated is the North Sentinelese. But even these might not have been totally isolated from other people in the Andamans for the past five centuries. And the other Andamese have been in contact with outsiders.
I find it impossible. The island has been reasonably near to world trade routes for millenia. And as stated outsiders have been to the island.
  #77  
Old 03-05-2016, 12:23 AM
Shagnasty Shagnasty is offline
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Originally Posted by AK84 View Post
I find it impossible. The island has been reasonably near to world trade routes for millenia. And as stated outsiders have been to the island.
Foreigners having been there isn't the claim. They kill many of the people that show up in short order. What is claimed is that they are so isolated that they have maintained a Stone Age culture to this day and fight so fiercely against outside interference that the Japanese government decided to protect them for their own sake but also for the sake others. I can't say what their ancestry is but they definitely live an extremely unusual and isolated lifestyle to this day. It is a very unusual case of isolates.

You can read all about them but little is known because they are unapproachable and they can't speak in any common language. If you know more about their heritage than I do or anyone else in anthropology please share it because there are lots of people that would love to know.

Here is a video of a group trying to approach them by boat:
https://www.youtube.com/watch?v=OaPYwlXOTzQ

Last edited by Shagnasty; 03-05-2016 at 12:27 AM.
  #78  
Old 03-05-2016, 12:58 AM
Colibri Colibri is offline
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Originally Posted by Shagnasty View Post
Foreigners having been there isn't the claim. They kill many of the people that show up in short order. What is claimed is that they are so isolated that they have maintained a Stone Age culture to this day and fight so fiercely against outside interference that the Japanese government decided to protect them for their own sake but also for the sake others. I can't say what their ancestry is but they definitely live an extremely unusual and isolated lifestyle to this day. It is a very unusual case of isolates.
The question isn't whether they do this now, but whether they have done this for all of the past 500 years (or for that matter 2000 years). If you have evidence that they have done this for several millenia please provide a cite.
  #79  
Old 03-05-2016, 01:16 AM
Blake Blake is offline
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Originally Posted by Shagnasty View Post
What is claimed is that they are so isolated that they have maintained a Stone Age culture to this day...
How is maintaining a stone age culture in any way evidence of being "so isolated"? Northern Australian Aborigines maintained a stone age culture up to the WWII, and were engaged in annual international trading events.

Quote:
... and fight so fiercely against outside interference that the Japanese government decided to protect them for their own sake but also for the sake others.
The Japanese government is protecting Indian citizens?

Quote:
You can read all about them but little is known...
Well we know enough to know that you are wrong when you claim they don't use fire. And we know enough to be highly skeptical of your claims that they don't wear clothes. And we know enough to know that you are wrong when you claim that:

Quote:
...they are unapproachable..

Finally, on 4 January 1991, Mr Pandit and his colleagues were met on the beach by a party of 28 men, women and children, for once unarmed. 'They may not have chiefs, but a decision had obviously been taken by the Sentinelese to be friendly towards us,' Mr Pandit said. 'We still don't know how or why.'

Now, the anthropologists have learned to remove most of their clothes, watches and spectacles before visiting the Sentinelese and the Jarawa, another isolated tribe. 'I've lost half a dozen pairs of glasses,' lamented Mr Pandit, who has been stripped naked by the islanders on several occasions. 'Clothing doesn't make much sense to them,' he said. 'They're curious about what we're trying to hide underneath.'



An administrative decision was made to stop these visits C2000, but any claim that they are unapproachable is utterly false. They are extremely cautious and prone to hostility, but approachable given time.


Quote:
If you know more about their heritage than I do...

Given your claims that these people do not use fire, do not wear clothes and are totally unapproachable, I suspect that it wouldn't be too hard to know more than you do. 3 minutes on Google seems to be sufficient.

Last edited by Blake; 03-05-2016 at 01:17 AM.
  #80  
Old 03-05-2016, 01:22 AM
Shagnasty Shagnasty is offline
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Well, no. There is no particular burden of evidence here. Historians claim that the Tudor monarchs were descended from William the Conqueror. EVERY single Tudor monarch. All it takes is a single case to disprove that. Nonetheless the burden of proof isn't on historians making the claim.
Oh boy, we are reversing position here from our previous debate. The specific claim is that every person on Earth is at least a 50th cousin of everyone else. I say prove it because there are good reasons to think that isn't true in the case of isolated populations. If even two people on Earth are isolated by several thousand years of genealogy, they are not within the 50th cousin range.

Quote:
Did you read my earlier posts? They weren't very isolated at all 300 years ago, they were living amongst their neighbours.
Their heir nearest neighbors are on an island chain in the Indian Ocean. It is huge and means nothing because you gave no evidence that they ever even met or interbred. There are related populations in the very general area but they claim don't know any more about them than we do.

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French is not mutually intelligible with Italian or any other in the world. Nonethless they were the exact same language just 2000 years ago. Mutual intelligibility tells us that languages are closely related. A lack of mutual intelligibility tells us exactly nothing.
Interesting. Explain how the languages of North Sentinel Island and its nearest neighbors are related to each other. No one including their closest neighbors has any idea what even the most basic rules of their language even consists of. It seems to be completely unrelated to all others.

Quote:
All humans use fire. You are actually claiming that they are not human?Of course they use fire, just like all other humans. Not only do they use fire, they have some rather sophisticated methods of controlling fire, including lamps and torches.
.

I didn't say 'use fire'. I am sure that they have at some point when lightning struck. What I did say was that they didn't know how to make fire. That is backed up by cites and observations. That is one of the reasons they are so hard to locate. They simply disappear into the foliage when they sense danger and there are no tell-tale signs of smoke to give away their positions.

http://mentalfloss.com/article/23973...entinel-island

This isn't supposed to be an argument between you and me. I find the topic fascinating and I have looked up everything I can on it. You can do the same. There are plenty of web sites and even some limited Youtube video documentaries from reputable sources that describe what is known about the Sentinalese. It isn't much but what is known is quite intriguing.

Last edited by Shagnasty; 03-05-2016 at 01:27 AM.
  #81  
Old 03-05-2016, 01:40 AM
Shagnasty Shagnasty is offline
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Originally Posted by Blake View Post
How is maintaining a stone age culture in any way evidence of being "so isolated"? Northern Australian Aborigines maintained a stone age culture up to the WWII, and were engaged in annual international trading events.



The Japanese government is protecting Indian citizens?



Well we know enough to know that you are wrong when you claim they don't use fire. And we know enough to be highly skeptical of your claims that they don't wear clothes. And we know enough to know that you are wrong when you claim that:



Finally, on 4 January 1991, Mr Pandit and his colleagues were met on the beach by a party of 28 men, women and children, for once unarmed. 'They may not have chiefs, but a decision had obviously been taken by the Sentinelese to be friendly towards us,' Mr Pandit said. 'We still don't know how or why.'

Now, the anthropologists have learned to remove most of their clothes, watches and spectacles before visiting the Sentinelese and the Jarawa, another isolated tribe. 'I've lost half a dozen pairs of glasses,' lamented Mr Pandit, who has been stripped naked by the islanders on several occasions. 'Clothing doesn't make much sense to them,' he said. 'They're curious about what we're trying to hide underneath.'



An administrative decision was made to stop these visits C2000, but any claim that they are unapproachable is utterly false. They are extremely cautious and prone to hostility, but approachable given time.





Given your claims that these people do not use fire, do not wear clothes and are totally unapproachable, I suspect that it wouldn't be too hard to know more than you do. 3 minutes on Google seems to be sufficient.
That is an interesting cite Blake and I appreciate you sharing it but it didn't refute much of what I said. All it said was that it took over 20 years for a dedicated group to approach them through persistence. nothing about language and nothing about fire.

I made a mistake earlier when I referenced their island as being under Japanese jurisdiction when it is actually Indian (that I correctly referenced earlier). That was simple carelessness on my part.

This isn't a debate and especially not a personal one. I just think it is fascinating that there are isolated tribes of people still left in the world that want to remain that way.
  #82  
Old 03-05-2016, 02:21 AM
Blake Blake is offline
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Originally Posted by Shagnasty View Post
Oh boy, we are reversing position here from our previous debate.
No idea what that means. Don't think I want to.

Quote:
The specific claim is that every person on Earth is at least a 50th cousin of everyone else. I say prove it because there are good reasons to think that isn't true in the case of isolated populations.
What are these isolated populations and what are the good reasons. We've laready given you our good reasons for believing that it is true.

Quote:
If even two people on Earth are isolated by several thousand years of genealogy, they are not within the 50th cousin range.
And if even one frog has wings it won't bump its arse on the ground when it hops.

Name these people who could have potentially have been isolated by several thousand years of genealogy?

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Their nearest neighbors are on an island chain in the Indian Ocean.
Yes, and the nearest neighbours of Kyushu are on an island chain in the Pacific Ocean. That doesn't indicate that Okinawans never lived on Hokkaido.

What's point do you think you are making?

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It is huge and means nothing because you gave no evidence that they ever even met or interbred.
Well let's correct that shall we:

There is also the story of a Sentineli who grew up among Onge, best told in the unavoidable Portman's own words. The story illustrates the degree of uncertainty surrounding things Andamanese even when one of the best-informed authority in the field is involved:

The North Sentinel Island was visited on the 15th of February 1895, and I took some Onges over there from the Quince Islands, as I had learnt at their camp there that one of them was a Sentinels, who had, some years before, left the North Sentinel in a canoe and come across, via Rutland Island, to the Quince Islands and the Little Andamans.

...

From my very slight knowledge of the Onge language, it is quite likely that I misunderstood the supposed Sentinels, and he may either have been driven away from the Sentinel in a storm, possibly as a child, and have been adopted by the Onges when he reached them on the Quince Islands, (the adults with him being killed), or there may really be occasional intercourse either between the Sentinel Jarawa and those on Rutland Island, or between the former and the Onge.

It was interesting to note that, unlike their behavior when in the jungles of the Great Andaman, the Onges on each occasion that they have been on the North Sentinel, have taken the lead in searching the forest for Jarawa [=Sentineli], and seemed to have no fear of them.



OK, so now that's settled.


Quote:
Interesting. Explain how the languages of North Sentinel Island and its nearest neighbors are related to each other.
Why should I do that? You made the claim that lack of mutual initelligibility is evidence of lack of relationship. I used the example of French and intelligent to show that such a claim is illogical nonsense. Nobody ever claimed that the languages definitely are related (they probably are, we don't know). I simply demonstrated that your claim that the languages aren't related because of lack of intelligibility is rubbish. A lack of mutual intelligibility tells us nothing.

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No one including their closest neighbors has any idea what even the most basic rules of their language even consists of. It seems to be completely unrelated to all others.
Yet another claim about the Sentinelese that you post as fact, and that is once again untrue.

We know approximately nothing about the langugae. It could be very closely related to the other Andaman languages. We simply lack any information either way.

The Onge had a name for North Sentinel Island and knew of the island's existence; they also appear to have recognized some degree of relationship when brought into contact with Sentineli. ... A comparison of the languages could perhaps answer this question but with the Sentineli language virtually inaccessible, there is nothing to compare with.

The Onge were terrified of the Sentinelis and the frustrated scientists could not even clearly establish from the shouted exchange between Onge and Sentinelis... whether the latter understood at least a little of the formers' possibly related language.



And that is approximately everything known about the degree of understanding their closest neighbors have about the language. your claim that their nearest neighbours know nothing is ignorant nonsense. We have absolutely no idea how much their neighbours understand. It could be a lot, it could be nothing. We just don't know. But whereas actual anthropolgists and linguists acknowledge this, you boldly proclaim certainty that nothing is known.

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I didn't say 'use fire'.
What the actual fuck?

Quote:
Originally Posted by Shagnasty View Post
they don't use fire
Quote:
Originally Posted by Shagnasty View Post
they don't use fire
Quote:
Originally Posted by Shagnasty
What I did say was that they didn't know how to make fire.
Quote:
Originally Posted by Shagnasty View Post
they don't use fire
Quote:
Originally Posted by Shagnasty View Post
they don't use fire
Quote:
Originally Posted by Shagnasty View Post
they don't use fire

Quote:
That is one of the reasons they are so hard to locate. They simply disappear into the foliage when they sense danger and there are no tell-tale signs of smoke to give away their positions.
Utter fucking rubbish.

The earliest known mention of the Sentineli was published by the British surveyor John Ritchie who wrote down the following observation in 1771:

... and if we may judge from the multitude of lights seen upon the shore at night, it is well inhabited.
...
. The islanders themselves were seen only by their torches at night or glimpsed as tiny specks on the beach from afar.


A fire spotted on an island inhabited by the Sentinelese tribe was unconnected to the missing flight,.... "But we believe it has nothing to do with the missing Malaysia Airlines plane," he added, saying that it was possible that the fire was lit by the tribe, who are known to burn thick grassland.

In what way does this support any of the claims that you have made? It doesn't mention the people not using fire, in fact exactly the opposite. It doesn't mention them not making smoke. It doesn't mention them being hard to see because of a lack of fire.

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This isn't supposed to be an argument between you and me.
No, it's supposed to be about presenting facts and fighting ignorance. You have no facts and keep making ignorant statements.

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I find the topic fascinating and I have looked up everything I can on it.
And yet you keep making claim after claim that I can refute with references in 3 minute using Google?

Let's see what you have said:

1) They don't use fire: Proven wrong with your own references.
2) They don't wear clothes: Proven wrong in 15 seconds with a Google image search.
3) They are unapproachable: Proven wrong in 2 minutes on Google.
4) They don't make smoke or light with their fires and thus are hard to detect: Proven wrong in 12 seconds on Google.
4) We know that their nearest neighbours don;t understand anyhting of their language. Proven wrong using the previous Google link. No time needed.

Quote:
There are plenty of web sites and even some limited Youtube video documentaries from reputable sources that describe what is known about the Sentinalese. It isn't much but what is known is quite intriguing.
It isn't much, but it all disagrees with what you have posted. It's quite amazing. We only know about ten things about the Sentinelese, you posted on five of them, and on four you were completely wrong. The only thing you got right is that they use stone age technology. Every other statment you made was wrong.
  #83  
Old 03-05-2016, 02:38 AM
Blake Blake is offline
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Originally Posted by Shagnasty View Post
... they are unapproachable..
MeAny claim that they are unapproachable is utterly false. Here is reference from a team of anthropologists who approached them many times over many years.
Quote:
Originally Posted by Shagnasty View Post
That is an interesting cite Blake and I appreciate you sharing it but it didn't refute much of what I said.


No, aside from the fact that you said they are unapproachable and my reference documenting multiple intimate approaches, it doesn't refute much at all.
  #84  
Old 03-05-2016, 04:49 AM
JohnClay JohnClay is offline
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I'm not sure about the math but perhaps being at most 50th cousins means that for the past 50 generations there are no ancestors in common. So if you go back 50 generations all 50 great-great-great-etc grandparents would be different. That's 2 ^ 50 g.g.g....grandparents... which is about 10 ^ 16 or 10,000,000,000,000,000 of them that all must be different.

Last edited by JohnClay; 03-05-2016 at 04:52 AM.
  #85  
Old 03-05-2016, 10:56 AM
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Let's ignore questions of population genetics for this post and just clarify terminology.

Are 50th cousins 6 times removed considered to be "50th cousins" for the purpose of OP's question? Or, would only a 47th cousin 6x removed qualify? (The same consanguinity as 50th cousins with no removal.)

I'll wait for this to be clarified before attempting any detailed guesstimations. Yes, there will be sixth removals and worse necessary in the intriguing difficult question. Other difficulties include estimating permeabilities, the effects of plagues and pogroms, social barriers to interbreeding, etc.

Now I'm going to guess that two Han Chinese, chosen at random would probably be 20th-cousins or better, and two Europeans probably 25th cousins or better. How about pick a European at random and a Asian mainlander at random? Wild guess: 99.9% to be 35th cousins or better; 99.99999% chance to be 40th cousins or better; perhaps 100% to be 41st cousin if the criterion excludes extremely remote people.

These are wild-ass guesses, and could be off by orders of magnitude. The critical distance, beyond which 99.99999% changes to 100% is definite but unknowable. It could be there is an old monk in Tibet and when he dies, the 100% mark shifts from 43rd cousins to 39th cousin.

While an omniscient being would know exactly what that 100% mark lies, the most we can hope for is something like:
Picking any two humans on the planet randomly there is a
  • about 0.2% chance they'll be 15th cousins or better
  • about 5% chance they'll be 20th cousins or better
  • about 98% chance they'll be 30th cousins or better
  • about 99.7% chance they'll be 35th cousins or better
  • almost surely at least 99.999% that they'll be 45th cousins or better
  • probably at least 99.9999% that they'll be 45th cousins or better
  • 90% certain that they'll always be 50th cousins or better
  • 99.9% certain that they'll always be 55th cousins or better
I'm NOT saying these vague guesstimates are the correct numbers. The important thing to note is that there are two levels of probability asserted.

There certainly is a Nth-cousin relationship which is the closest single-path consanguinity guaranteed between any two living humans. And what that guaranteed N is changes over time. Surely it was once much more than it is now -- communication between, say Africa and Australia, was very minimal thousands of years ago. Perhaps N spiked sharply down, some fixed delay after the arrival of Columbus et al in the New World.

But whatever N is, we can only guess it. Above I guess there is a 90% chance Colibri is right and 50th-cousinship is guaranteed (but please review the terminology question in the first sentence above). But if I were to write "It is almost completely certain that the cousin distance is always N or less" I would agree with Shagnasty and hedge my bets by choosing, say, N = 60.

More definitive answers would depend on anthropological facts: how fast do genes diffuse through the Amazon jungle? I'll guess that even thousands of years ago, slaves were trafficked from one part of that basin to another; no?
  #86  
Old 03-05-2016, 02:21 PM
UltraVires UltraVires is offline
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I skipped to the end so forgive me if this has been covered, but I remember reading an article that there is a particular point in the past at which every single human on the planet was either: 1) an ancestor to every single person now living, or 2) an ancestor to nobody now living. I recall that that date in the past was no so long ago.

And I also remember that if you limit #1 to descendants of a particular ethnic lineage (those of European or African descent) then it is shockingly recent.

Does any of this sound familiar or am I way off base?
  #87  
Old 03-05-2016, 02:29 PM
yabob yabob is offline
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I skipped to the end so forgive me if this has been covered, but I remember reading an article that there is a particular point in the past at which every single human on the planet was either: 1) an ancestor to every single person now living, or 2) an ancestor to nobody now living. I recall that that date in the past was no so long ago.

And I also remember that if you limit #1 to descendants of a particular ethnic lineage (those of European or African descent) then it is shockingly recent.

Does any of this sound familiar or am I way off base?
I've heard about 1000 years for Europe. Interestingly, this implies that if somebody tells you they're descended from William the Conqueror (1028-1087), and you are of European ancestry, you can reasonably say "Well, in all likelihood, I am too".
  #88  
Old 03-05-2016, 03:22 PM
UltraVires UltraVires is offline
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I've heard about 1000 years for Europe. Interestingly, this implies that if somebody tells you they're descended from William the Conqueror (1028-1087), and you are of European ancestry, you can reasonably say "Well, in all likelihood, I am too".
Right. When I first started genealogy, I was excited that I was descended from William the Conqueror and Charlemagne. It turns out that every white person in the world shares the same lineage.
  #89  
Old 03-05-2016, 04:40 PM
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Right. When I first started genealogy, I was excited that I was descended from William the Conqueror and Charlemagne. It turns out that every white person in the world shares the same lineage.
I have an expert-approved descent from William the Conqueror's sister, who, like William, has a known descent from Charlemagne. However I've no approved descent from the Conqueror (though doubtless there are such lines unknown to or unsanctioned by the experts). (Is your descent from the Conqueror expert-approved? Care to post it?)

It's probably true that every Frenchman or Englishman has a (probably unknown) descent from William the Conqueror but I'd be reluctant to extend this confidently to "every white person in the world."
  #90  
Old 03-05-2016, 04:50 PM
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Here's a pdf paper which uses a computer simulation to guess that the Identical Ancestor Point for all humans is 7400 (4200) years ago, and the MRCA point is 3400 (2000) years ago. (The parenthesized numbers are for liberal mobility.) The conservative estimates correspond to, roughly, 274 generations for IAP and 126 generations for MRCA. (The 51-generation estimate in thread title is for yet another problem.)
  #91  
Old 03-08-2016, 09:00 AM
aldiboronti aldiboronti is offline
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My son recently had his family tree traced professionally. It turns out my ex-wife and I are descended from two daughters of Edward I, Joan of Acre and Elizabeth, which makes us cousins in whatever degree. The genealogist explained to my son that the royal connection was no big deal as most people of English descent tie in to royalty if you go back 7 or 8 centuries.
  #92  
Old 03-08-2016, 09:41 AM
wevets wevets is offline
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Originally Posted by Shakester View Post
There are living full-blood Australian Aborigines, and while they were never completely isolated from the rest of the world in the way that the Tasmanian sub-group were, they were mostly isolated from everyone except for near neighbours from their arrival in Australia at a very minimum of 40 000 years ago, and most likely 50 to 60 000 years ago.

Mostly is the most important word in that paragraph...

Quote:
So there's no way they have have a recent common ancestor with modern European/African/Asian populations. Anyone claiming they do is tripping. There is no way on Earth that they can possibly share an ancestor with modern Europeans any more recently than way over 40 000 years back.
This paragraph is nothing but unsupported balderdash...

Quote:
We find an ancient association between Australia, New Guinea, and the Mamanwa (a Negrito group from the Philippines), with divergence times for these groups estimated at 36,000 y ago, and supporting the view that these populations represent the descendants of an early "southern route" migration out of Africa, whereas other populations in the region arrived later by a separate dispersal. We also detect a signal indicative of substantial gene flow between the Indian populations and Australia well before European contact, contrary to the prevailing view that there was no contact between Australia and the rest of the world. We estimate this gene flow to have occurred during the Holocene, 4,230 y ago. This is also approximately when changes in tool technology, food processing, and the dingo appear in the Australian archaeological record, suggesting that these may be related to the migration from India.
https://www.jstor.org/stable/4199212...n_tab_contents (bolding added)

Last edited by wevets; 03-08-2016 at 09:42 AM.
  #93  
Old 03-08-2016, 01:46 PM
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This idea of "Look at these people over there. They're so far away from everybody else they have to have been genetically isolated for millennia." needs to be rethought.

The two most widely separated people, genetically, are the Hazda of east central Africa and the Koi-San of southwest Africa. Note that these people are on the same continent and have been significantly affected (genetically and linguistically) by the Bantu expansion. So, despite their differences, there has to be some moderate degree of cousin-relatedness.

Compared to them, most everybody else: Europeans, Asians, Native Americans, and Native Australians are much more closely related. Cousin-wise, as far as DNA can tell, those are all more closely related than the Hazda to the Koi-San.
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Old 06-10-2016, 10:30 PM
JessicaHoyt JessicaHoyt is offline
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What about Native Hawaiians? They seem more cut off from everybody until the late 1700s when it was discovered. There was some contact between Siberia and Alasa even after the land bridge froze (basically until the border was forcibly shut down as the "Ice Curtain" in the 1940s due to thee Cold War) and possibly between Greenland and Iceland. Not sure if there was contact between Indonesia and Australia.

However, who would have had contact with Hawaii? Even some sole sailor blown off course would probably not be enough to connect it to the whole gene pool. And I'm sure there are still at least some Native Hawaiians who don't have mainland ancestry.
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Old 06-10-2016, 11:52 PM
Riemann Riemann is offline
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Quote:
Originally Posted by JessicaHoyt View Post
What about Native Hawaiians? They seem more cut off from everybody until the late 1700s when it was discovered. There was some contact between Siberia and Alasa even after the land bridge froze (basically until the border was forcibly shut down as the "Ice Curtain" in the 1940s due to thee Cold War) and possibly between Greenland and Iceland. Not sure if there was contact between Indonesia and Australia.

However, who would have had contact with Hawaii? Even some sole sailor blown off course would probably not be enough to connect it to the whole gene pool. And I'm sure there are still at least some Native Hawaiians who don't have mainland ancestry.
Are you planning to resurrect this every few months or years and ask about another isolated population that you just thought of?

To recap: the reason that the model prediction for a quite recent genealogical (either parent) MRCA for the entire human population is robust is that an isolated population must remain absolutely isolated in order to seriously violate the assumptions of the model. All it requires for a single member of an isolated population to outbreed. Once you have a genealogy linking any one member of an isolated group to the rest of humanity, then panmictic breeding within the isolated group will rapidly ensure that everyone within that group now has a lineage tracing back to the rest of humanity. So yes, "some sole sailor blown off course" would be enough to connect it to the rest of humanity.

And thus the mathematics show that there is no burden of proof to check every last human being. If any member of a putatively isolated group is related to the rest of humanity, then it is certain that they all are within a fairly small number of generations.

Last edited by Riemann; 06-10-2016 at 11:56 PM.
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