Added: 4 months ago
From: C0nc0rdance
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  • I LOVE THE MATH! DON'T LET UP ON THE MATH MODELING!

  • @mphello Please rephrase terms like "identical ancestor point" in terms of existential and universal quantifiers and nodes and edges in graph theory. Thanks!

  • Goolge Image the word "phylogenetic tree".

  • YES I read some similiar in a bbok

  • I can only begin to imagine how you have time to keep up with so many comments on this stuff o.O

  • It really bothers me that this video doesn't have more dislikes.... This is terrible science.

  • @MetroAdventures i LOVE how you say that but dont say why

  • Bais Bias Bias Bias! Isolated populations, man! Isolated populations!

    Some tribes did not interbreed with Eurasian people for thousands of years!

  • One thing i love about your vids is that you are able to explain what you do videos about clear and easily understood,hey we all can't be scientist

  • what happened to the genetic bucket chain part 3?

  • Interesting observation: supposedly, ethnic Arabs are descended from Abraham's son Ishmael, while ethnic Jews are descended from his son Isaac, specifically through Isaac's son Jacob/Israel. Yet, if those were in fact real people, and lived sometime between, say, 2000 and 1600 B.C.E., then everyone on Earth is likely descended from both Jacob and Ishmael.

  • If each descendant of yours has two children, and your descendants NEVER mated with each other, it would take 33 generations (825 years at 25 years per generation) to have over 8 billion descendants. (Of course, your descendants quite likely WILL mate with each other at some point.) So, if your descendants migrated a lot and were open about interracial marriage, you'd be the ancestor of most people on Earth within a thousand years.

  • So Adolf Hitler was in secret my great grandfather?

    Shit...

  • You are very severely underestimating inbreeding. The

    Neanderthal ancestry is found by analysing autosomal DNA, not mitochondrial DNA.

    No North Asian autosomal markers whatsoever are found in African populations, for example. No 'Neanderthal' markers are found in Africans - even if those are not 'Neanderthal', they would have been present if there was interbreeding. Groups that end up dissimilar on IBS SNP analysis share no recent common ancestry.

  • @Humanophage

    Factually false:

    Am J Hum Genet. 2002 May; 70(5): 1197–1214.

    "A Back Migration from Asia to Sub-Saharan Africa Is Supported by High-Resolution Analysis of Human Y-Chromosome Haplotypes"

    You can read more if you research M207, which is now called UTY2. It is a lineage marker found in Central and Northern Asia, and also in some populations in Cameroon. Many Africans possess autosomal markers for the near East and Europe.

    However, genetics is diluted over time ancestry is not.

  • @C0nc0rdance Near east... NOT confucious.down to the Cape of Good Hope or to the Andaman islands...

  • my head exploded

  • I understood what you were saying in the video but what about African people who never mixed whit any European or other races? I am just curious.

  • and another reason why racists are morons...

  • confusis might have being hell of a lover. but compared to kengish khan he was small time.

  • What you're saying is demonstrably false. It may be true for some cases, but you've stated that everyone human alive is descended from every historical figure from 2000 years ago or more. This necessarily includes people who didn't even procreate. How exactly does that work? By extension, you're also implying that every person alive today will be the ancestor of every human at some point in the future, again even if they don't procreate, or their progeny do not procreate.

  • I find this really fascinating. Must look more into it.

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  • I think it is a mistake to try and link this fascinating bit of statistics to racism and its futility. Racism/nationalism/tribalism all have more to do with finding a target for various problems. The 'us vs. them' response. Human psychology doesn't depend on logical veracity.

  • Thanks C0nc0rdance, you broke the cool factor of Assassin's Creed :(

    (I kid)

  • If you are claiming that everyone is actually related as recently as 1000 years ago, then one isolated tribe would prove your claim false If you are merely claiming that it is statistically likely that everyone is related, then you are not accounting for what actually took place.

    The math stays the same even if half the population was taken to Alpha Centauri 1000 years ago, and we would know that there was no cross breeding. Isn't the truth via DNA testing more interesting?

  • @wwickeddogg

    By all means. Look up Haplogroup X2a, which paints an interesting picture of repeated gene flow from Siberia to North America. Unfortunately, the genetic evidence of mixing is often concealed by the partial inheritance of autosomal alleles. This is discussed in Part 2. The bucket chain of ancestry is NOT a genetic bucket chain.

    I'm not averse to challenges on the evidence. Present a counter-case, and I'll try to respond when I can. Might be interesting.

  • @C0nc0rdance Ok, well I read this article: Fine-scaled human genetic structure revealed by SNP microarrays and if my understanding is correct, then your conclusion is correct.

    My only point is that I hate statistics and if you can prove your point with real science, then why use statistics?

  • If you are claiming that everyone is actually related as recently as 1000 years ago, then one isolated tribe would prove your claim false If you are merely claiming that it is statistically likely that everyone is related, then you are not accounting for what actually took place.

    The math stays the same even if half the population was taken to Alpha Centauri 1000 years ago, and we would know that there was no cross breeding. Isn't the truth via DNA testing more interesting?

  • Concordance, big fan of your videos, commenting for the first time. I understand the idea with the bucket chain, but is there enough time for this to take place? Caesar lived ~2k years ago. If we assume the average pregnancy age being 16, that's 125 generations, and the distance between Beijing and Paris being 8238 km, each generation would have moved entire 65km exactly to the east. While it might not sounds like much today, that's three days march on a good road. Surely you see a problem here.

  • @Yupiyeahs you don't think that on average a single individual from each generation could migrate "three days march" in their life-time? also considering travel by boat, that is plausible if not probable or even innevitable.

  • @Sahuagin No, I do not. 65 km was an incredibly long distance until very recently. Boat travel is what Concordance describes as "brave, adventuring soul" (or something along those lines) and isn't relevant to the bucket chain mechanic.

  • @Yupiyeahs 1: it's an average. you don't need a single person per generation to migrate that far if 1 individual every 10 generations migrates 10x as far, for example. 2: you only need a single individual to make that journey. that's 1 individual out of possibly ten's or hundred's of thousands.

    the amount of restriction you are describing it makes it sound like migration cannot ever occur.

  • @Yupiyeahs (also note that I am assuming your estimations are accurate, which they may or may not be)

  • @Sahuagin 1. My only estimation is the average pregnancy age. If you feel that 16 is too high or too low, you may adjust it yourself. It doesn't really work under the age of 13 too well, as you're probably keenly aware. The time passed since Caesar death and the Paris-Beijing distance are easily verifiable facts.

    2. Yes, that would be the "adventurous soul" example. Once again, that's not what we're talking about. Please refer to the second video.

  • @Yupiyeahs

    The Austronesians, in outrigger canoes, went as far east as Madagascar, and as far west as Hawaii (at least). Look up "Austronesian peoples", I think you'll be amazed... at least I was.

    The Austronesians include the Polynesians, who ruled a far-flung ocean empire prior to European colonization.

    History is so awesome!

  • @C0nc0rdance I agree with the last statement, but do you not think that large scale migrations (e.g. 400~850 AD Voelkerwanderung) or conquests are somewhat different to the example you've given in your latest video. The argument for overcoming the distances and cultural borders was the idea that people in neighbouring villages can intermarry, thus allowing a gradual movement of offspring to other regions. This has nothing to do with migrations of entire peoples due to e.g. food shortages.

  • @Yupiyeahs

    Not sure I follow the difference. It doesn't have to be a single individual moving. The idea was that a person need not go very far from their place of origin in order to be part of a chain of events that moves ancestry quite far.

    Can you clarify a bit? You object to the example ("A marries B"), or the underlying model of Rhodes et al?

    I suspect that trade was more responsible for the spread than large migrations or imperialism/colonialism.

  • @C0nc0rdance I don't object to the idea of marriage between villages and the subsequent spread of offspring, I simply doubt that an individual living in a non-mobile society (e.g. Germanic village at the turn of the era) could eventually have his hereditary line end up in China, Latin America, etc. through that mechanism alone in mere 2000 years. The distance that would have to be covered is simply too long for the few generations that lived since then. (cont.)

  • @Yupiyeahs I find the entire concept quite intriguing and, by all means, plausible. My only quarrel is with the fact that they're claiming that it happened so recently..

  • @Yupiyeahs

    Not sure I follow the difference. It doesn't have to be a single individual moving. The idea was that a person need not go very far from their place of origin in order to be part of a chain of events that moves ancestry quite far.

    Can you clarify a bit? You object to the example ("A marries B"), or the underlying model of Rhodes et al?

    I suspect that trade was more responsible for the spread than large migrations or imperialism/colonialism.

  • @C0nc0rdance (cont.) I imagine that far trade, e.g. Silk Road and East India Company, could transport Caesar's offspring to distant rural settlements. However, one begs to ask whether that mechanism is very effective (i.e. out of the very few Europeans who had children outside of the Occident prior to the colonial era, how many were actually related to Caesar?) and whether these can be illustrated by a model? Unlike inter-village marriages, these couplings would be sporadic at best.

  • @C0nc0rdance 5:24 ..."everyone alive at the time was either the direct ancestor of everyone alive today or the ancestor of no one alive today" How can someone be the ancestor of someone who is not alive? I understand the main theses of the video, it is just the comment is so general it sounds ambiguous,

  • @DeepThoughts42 "How can someone be the ancestor of someone who is not alive?"

    what? dead people have ancestors, too...

    for those people that are the "ancestor of no one alive today", it means that of all people currently living, not one is a descendant of those ancestors (since all descendants of that ancestor have died; ie: their lineage went extinct at some point in the past)

  • @Sahuagin A person is born. He dies before he has any children. Can we call him an ancestor of anyone?

  • @DeepThoughts42 in that case he has zero descendants, but he can still be said to be "the ancestor of no one alive today"; he just also happens to be "the ancestor of no one".

  • sadly I'm no expert ! but the aboriginal autralians were surely isolated from much of the world for tens of thousands of years. the common ancestors we share must surely be before this physical isolation occurred?

  • Well, given my current track record, looks like I'll be part of the 20% that died out. It's not so bad, my non-children won't have to deal with all the problems the 80%'s kids will.

  • Man, that's fascinating. I'm wondering about the indigenous peoples of, say, Australia, though. I need to go find out some stuff about this.

  • @RandomRationale You might as well be saying how a person defines "subspecies" would be debatable. I will stick with science when it comes to defining "race," you however can debate about how terms like "race" should be defined all you want, science is not a democracy, I wont take you seriously nor will science until you produce peer reviewed science that demonstrates why race is defined the way you say it is. Racial differences are seen and understood more clearly thanks to biology.

  • Hmm. Knew it. Deep down I always did.

    So if I were to say that "racism" and all these other "isms" are, in reality, concepts designed to divide and conquer, I'd be right, right?

  • Holy sh*t I've never realized this. I've known, but not let it sink in. I cannot really fathom it and am unwilling to believe this is true, but as a mathematician, I cannot deny the number issue so I concur that is must be true. It's just so incredible.

  • Wait what about Inuits and other Native Americans?

  • C0nc0rdance: Disproving human evolution by proving that animal evolution doesn't apply to humans.

    Good job c0nc0rdance. Good job contradicting everything Darwinian evolution has taught us. Good job telling us we're the exception to the animal rule. Bravo buddy... bravo.

    I hope your next video is going to be that you now believe in Intelligent Design, because that's where you are headed with this social “science” P.C. bullshit.

    Darwin would be rolling in his grave right now.

    Fucking lemmings.

  • @C0nc0rdance

    Are you saying that people(s) who have been geographically isolated for thousands of years are descended from Confucius? For example, aborigines in various parts of the world? I find that difficult to believe. Your assumptions in your models may be wrong. Your model seems to assume that people are not racist/xenophobic and will intermingle freely and that they have had enough time to do so.

  • @bruinjogger I agree. It would be more believable that all living Chinese people are descended in some way from Confucius, but maybe not the Inuit or Aborigines, or even all Europeans.

  • @bruinjogger I was about to make the very same point. Mathematically, it is very possible that we all descended from Confucius, but geographically, it's totally impossible. Just because our hypothetical Inuit had a lot of ancestors, doesn't mean that one of Confucius's kids made the trek across the arctic. Consider the Aborigine in Australia related to the ancient Maya. A common ancestor would have to go back a lot farther than three or four thousand years! Five thousand years? Quite possibly.

  • @bruinjogger i agree. even when people are same race of species. its still safe to say that very little mixing happend bechose of geological boundries. its like siberian tigers, and bengal tigers, can and will breed togheter if in same cage, but in wild they dont, becose the are geologicaly isolated. allso, even if you have children, that does not mean they survive, or that they pass on their genes. for example, even if you have village full of decendants, it does not mean a dick if they die.

  • @bruinjogger allso, i did not mean to say that races exist. cos they dont. i am mearly stating. that this ecuation asumes that there is no isolation. so i find it unliekly that american native in 1000 sentiry, whuld have decendet from julius cesar. now i do belive that julius cesar has living decendants in italy and spain. and i know that over 1% if the world is derect decendant of kegish khan. but i dont think this take account the fact that international travel has not allwasy existed.

  • 10 people don't like confucius... lame, i know lol

  • if we are, or at least can be, the direct descendents of Confucious less than 2500 years ago, why is it wrong to say we all are descendents of Adam and Eve 6000 years ago?

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  • @spiritualbully

    If you accept that those two people were living in a world that already had about seven million other people when they were born, then there is nothing scientifically wrong with saying that everyone is descended from a couple that lived 6000 years ago.

  • @tifforo1 but I don't accept that. 

  • @spiritualbully

    Byblos was likely settled before 6000 B.C.E. and became a city around 5000 B.C.E. Çatal Hüyük was likely inhabited by several thousand people living in plaster houses starting around 7500 B.C.E. Pit dwellings in Germany and Japan date back hundreds of thousands of years.

  • @tifforo1 what does that have to do with the world having 7 million people?

  • @spiritualbully

    There were groups of people of substantial size living in places around the world more than 6,000 years ago.

  • @tifforo1 be more specific and please try to support your claims with sources. How many people, how many places?

  • @spiritualbully

    Cloth and pottery from the Upper Paleolithic/Mesolithic and Neolithic have been found in many places around the world. The development of agriculture around that time also left traces. Flax was domesticated in Iraq in the 5000s BCE - Helbaek 1969. Fabrics from the 7th millenium BCE were found in Israel - Bar-Yosef 1985. Sheep were domesticated at least as early as 7200 BCE - Protsch and Berger 1973. For an early settlement, again refer to the Catal Huyuk example.

  • I'm not sure of the point of 2:00-2:20? You're providing an upper bound, that "you have no more than x ancestors," but I believe your point requires a lower bound, "you have at least x ancestors."

    Inbreeding is ignored, and so people are being counted multiple times, as you said. I think you need a metric (and evidence of its validity) of max inbreeding over time and calculate from there.

    I think it's necessary to show the lower bound is higher than the number of people who have ever lived.

  • @rtwhite1546 I'm sorry, the lower bound should come very close to the number of people who have ever lived if your model and hypothesis are correct. (Since we can't really calculate with certainty and some relatively modern people certainly are not ancestors.)

  • @rtwhite1546

    Please double check my math, by all means. You can have at most 2^n ancestors, where n=1 is your parents. If your mother and father were full siblings (ew!), then you'd only have 2 grandparents. So, the upper bound for n=2 is 4, and the lower bound would be 2. The lower bound of full sib mating is 1^n... so not a productive limit for our purposes.

    Of course, better yet, if you are interested in the math, is to read and analyze the papers by the Yale group, Rhodes and Chang.

  • Well, no, 1^n is just 1. At the very minimum (brothers and sisters every time), you would have 2n ancestors.

    Of course that's an unrealistically extreme case, but inbreeding of more distant relatives certainly occurs, which would give you a number of ancestors somewhere between 2n and 2^n, one of which goes over the number of people ever to live, while the other doesn't. Not to take away from the other arguments, but the math in the video is not useful. I will check out the paper sometime.

  • @rtwhite1546

    The minimum bound for full sib mating is 2 x 1^n in each generation, which remains 2 forever. In each generation, two parents give rise to two children who become two parents... 2n would be the accumulated sum.

    Yes, pedigree collapse requires progressive inbreeding coefficients. By the Middle Ages, fully 1/3 of your ancestors were first cousins. The point is that you have more POTENTIAL ancestors than the number of people who have ever lived.

  • @C0nc0rdance You're right, I was comparing a single generation in one case with total ancestors in another.

    After reading the paper, I see that it was meant as starting point, not a predictive model. The model assumes random mating (i.e. every person from one generation is equally likely to be the parent of any person in the next generation), and discrete and non-overlapping generations. The author suggests factoring geographical considerations, which would change the results tremendously.

  • @rtwhite1546

    The paper describes a Monte Carlo stochastic model that includes migration, variable radii, but not much population substructure. Those were careful guesses, but they still give a pretty big range, from say 500 AD to 1500 BC to the MRCA. Further refinements of these models might move the numbers up or down by a bit, but fundamentally, our MRCA is really quite recent, well within the period of recorded history.

  • mind->blown

  • Dammit Jim I'm a doctor not a mathematician!

  • I'd love to be related to Confucius. I don't care much for Caesar or Cleopatra, though.

  • Soooooo....we're all cousin f*ckers....

  • this doesnt count for turks

  • Surely, that tribe in Brazil that was spotted from a helicopter, that lives completely cut off from all civilization, and apparently has existed in that state of isolation since before the Europeans arrived is not descended from Confucius... unless some confucian DNA found its way to the New World with the Vikings.

  • @lazyperfectionist1

    I don't know. "Cut off from civilization" doesn't mean "no intermarriage with other peoples". They might live in close proximity to other tribes that they trade with. They might have raided nearby villages for wives in the recent past. This is different from enculturation.

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  • Flawed logic and assumptions. Go to the Isle of Wight.

  • @calmreason Could you elaborate a bit please?

  • Genghis Khan was the Boss of all Bosses when it comes to this.

  • The Tasmanian Aboriginals were isolated from the mainland for 10,000 yrs until less than 200 yrs ago, but sadly no "pure bloods" are left now.

    cheers

  • Taswegian too,nedladdy?

  • Maybe to an broad approximation, you have neglected to include populations largely isolated for more than 40,000 yrs, and another population totally isolated for 10,000 yrs.Sadly, we still neglect them in all sorts of ways. There are still "pure blood" Aboriginals in Australia now. There was probably contact via Cape York (the pointy bit at the top underneath Papua New Guinea) and the Torres Strait.

  • I think you're highly underestimating the inertia posed by social factors, historically. Not only was it more difficult to move geographically than now, but interbreeding was also discouraged in feudal societies, by caste systems, for other religious reasons or just simple xenophobia. While these factors are not set in stone, and can be overcome, they certainly existed and interbreeding difficult in many places. You might for example be cast out of society and risk having your genetic line die.

  • @Gameboygenius Interbreeding in feudal societies is an interesting one, as the divides between social status were stronger than the divides between people geographically. For example a Baron would be far more likely to marry someone of similar social status from a different kingdom, even a far away kingdom, than he would to marry a peasant girl from his own lands. Marrying beneath your station was a greater faux pas than marrying a woman who looked a bit different and didn't speak your language.

  • @Beelzeboogie Indeed, but the privileged classes constituted only a small portion of the population, and the peasantry the majority. And peasants often couldn't move very far geographically, either because they didn't have funds, or because they were under serfdom. Again, that is not to say that people definitely couldn't move, but I still see inertia factors there.

  • @Beelzeboogie

    Ahem. I hate to bring up an indelicate subject, but not all babies are born of the love between a wife and husband. The cultural divide between lord and serf was probably about as strong as that between slave and master in the pre-War American South. Raids and rape stir the pot, as unpleasant a fact as that is. Wars throughout history have left behind bastards.

  • @C0nc0rdance There is that as well. Marrying someone below your station may have been a big no-no, but raping them, that's another story.

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  • Forgive my ignorance, but weren't the Native American populations here in the Americans prior to the Egyptians and the other civilizations mentioned? So how can Natives be related or descend from Confucius and everyone of those famous figures? Assuming no admixture from colonization or current times. I watched the video, but can't remember what I saw/heard, and don't want to watch it again (now). Any help is appreciated, by anyone. Thanks.

  • @dUCHE55DUDE so you're saying that they just happened to spawn indirectly from our gene pool? they did come from somewhere... technically native americans were Caucasian/Asian descendants from the beiring(spl?) strait. so in way they were the closest related to him.

  • @somethindarker I'm not saying that at all. I know there is a relationship between Asians and Native Americans. I just want to know how can Native Americans descend from Confucius when Natives reached the Americas before he existed.

  • Respond to this video... Same goes with the other famous people mentioned in this video.

  • Nice fairy tale.

    But lets talk about probabilities.

    (If )2000 years are needed to get to the least common ancestor Z of all modern humans by probabilities.

    So today there are individuals X and Y :

    A) X has a ratio of descent from Z 1 / several tens of billions .(least ratio)

    B) Y has a ratio of descent from Z, almost 1 in 1.(biggest ratio)

    C)all the rest in between.

    Only a mad man concludes that x's ratio & y's ratio are comparable numbers, therefor justifies genetic similarity of X to Y.

    ...

  • @AmetReloads (2)

    ... IF the gene pool of any individual,is the product of the random combination of the genetic material of 2 individuals with in the population,in the population the X is part of, there isnt a sufficient number of individuals to even get close to the possibility of an offspring that would have genetic similarity to Z, even if all the rest individuals have a rate of ancestry from Z much greater than X's.

    So how does the above disprove races?

  • Nice fairy tale.

    But lets talk about probabilities.

    (If )2000 years are needed to get to the least common ancestor Z of all modern humans by probabilities.

    So today there are individuals X and Y :

    A) X has a ratio of descent from Z 1 / several tens of billions .(least ratio)

    B) Y has a ratio of descent from Z, almost 1 in 1.(biggest ratio)

    C)all the rest in between.

    Only a mad man concludes that x's ratio & y's ratio are comparable numbers, therefor justifies genetic similarity of X to Y.

    ...

  • well, i guess, unfortunately the main argument of the video appears to be wrong.

    it doesnt apply to everyone. a person with 100% cherokee or 100% zulu or 100% pygmy descent will almost certainly not be a descendant of any of these 3 people.

    the problem is that many individual populations of humans have been isolated for long timespans. only today this is changing. so you might be right maybe 5 centuries from now.

    but its still interesting, just incomplete/flawed.

  • @kurtilein3

    There are no 100% Zulus, simply because there are not enough Zulus in history to make up the ancestors even a few dozen generations back, when your ancestors were in the tens of millions.

    I'm afraid you didn't get the content here, or didn't watch the second part. If you still aren't getting it, I recommend the linked Nature paper that presents the formal models. It's not an intuitive conclusion, it's the unavoidable consequence of coalescent ancestry.

  • @C0nc0rdance "simply because there are not enough Zulus in history to make up the ancestors even a few dozen generations back, when your ancestors were in the tens of millions."

    That's a spurious reason though; as you admit, that number would collapse under cousin-marriages in a truly isolated population. The real reason there are no 100% Zulus is because the Zulus were not truly 100% isolated.

  • @C0nc0rdance actually i really just watched the first part when commenting here.

    the second part clarifies exactly the points im uncertain about, but i have to say im still skeptical. the mathematics work, but to apply the mathematical model to reality assumes that populations were not isolated. i could agree that its true for each city dweller, and that its true if you pick someone a bit earlier than confucius. but i dont think its completely proven for confucius and everyone on the planet.

  • @C0nc0rdance

    one thing i read about, i dont remember the name... but there was a beneficial mutation in humans that allowed the digstion of lactose in adulthood (all children can digest it, many adults cant). it has been tracked to about 5000 years in the past, central europe. today all europeans can digest lactose and a few other races got the gene as well, but most adult asians still cannot digest lactose. after 5000 years. and a beneficial mutation.

    i just dont see how to make it fit.

  • Nice fairy tale.

    But lets talk about probabilities.

    If 2000 years is needed to get to the least common ancestor of all modern humans, that is a number 1 / 700 trillion trillions .Lets call him Z.

    So today there are individuals x and y :

    A) X which has a ratio of descent from Z 1 / 700 000 000 000 000 000 000 000 000.(least ratio)

    B) Y which has a ratio of descent from Z of almost 1 in 1.(biggest ratio)

    C) and all the rest in between.

    ...

  • @RandomRationale Human and chimp genome 96% the same yet the 2 species are so different. It doesn't take much to make a species, races, subspecies, breeds..ect very different and biology demonstrates that very well. Biology helps us to understand the small genetic racial differences that have such a huge impact.

  • I never liked Inuk, he never comes to visit.

  • You just blew my mind. This is awesome :)

  • Makes you think...how in just decades a species of lizards put on a meridian island by researchers developed larger heads/tails and cecal valves muscles that slowed down food digestion in fermenting chambers, which allowed their bodies to process the vegetation's cellulose into volatile fatty acids. The lizards became vegetarians in just decades. Dawkins wrote a paper on it. We may all be descendants of Confucius but it didn't take much to make the human races very different from one another.

  • BCE ?

  • Brill! I am going to #2 NAWWWW

  • I'm related to Osama bin Laden & Pat Condell?

    I Win.

  • Doesn't this assume that people "mate" randomly ? I mean don't social factors (like white people refusing to have sex with black people and vice versa) cause problems ? I mean I'm probably wrong, but still I'd like an explanation.

  • @ForYeensSake

    The technical term you are looking for is panmictic (no barriers, full mixing). If we assume a panmictic population of 1 million people, the MRCA is about 20 generations ago.... or about 1400 AD assuming 30 yr generations.

    This research (Nature 2004 linked above) is based on stochastic barriers.... and covered in Part 2.

  • @C0nc0rdance I've now seen part 2. Thanks for answering =) (I sometimes just ask questions as they come up, even when I haven't seen the whole vid because I'll otherwise forget). Thanks for answering!

  • @C0nc0rdance I've now seen part 2. Thanks for answering =) (I sometimes just ask questions as they come up, even when I haven't seen the whole vid because I'll otherwise forget). Thanks for answering!

  • @C0nc0rdance

    “The effect of inbreeding on coalescence times is greater in large populations. … [The mean rate of pedigree growth] is much < 2 when inbreeding is prevalent and/or a high proportion of matings are trans-generation. Both of these conditions occur in natural populations, suggesting that previous studies underestimate the actual [timing of the most recent common ancestor of humanity].” Lachance “Inbreeding, pedigree size, and the most recent common ancestor of humanity” 2009.

  • @n00ffensebut

    I read this as well. Proper citation: J Theor Biol. 2009 Nov 21;261(2):238-47.

    Why didn't you include this quote?

    "Biparental coalescence times are remarkably recent (within the last 2500 years). This occurs regardless of the amount of inbreeding."

    Are you trying to argue against the central point using a paper that explicitly supports it?

  • @C0nc0rdance

    I thought your central thesis was that everyone is descended from Julius Caesar and Cleopatra, among others. You just admitted that the most recent common ancestor goes back further and that you read but did not cite a study that made the studies you cited outdated. It also demonstrates the fact that the entire enterprise is theoretical hand-waving that is contradicted by the absence of Neandertal DNA in Africans. Why are you trying to teach something you already know is false?

  • @n00ffensebut Although certain African populations have no Neanderthal DNA, they certainly have the same Homo Sapiens DNA as the rest of the world does.

  • @StellaOmega

    No, you have not been following science, either. It is unfortunate that YouTube makes the spread of ignorance so easy. Neandertals are Homo sapiens. Eurasians mixed with Neandertals. If this video were correct, then everyone would have Neandertal DNA. Green et al. Science 2010. 328: 710-722. And everyone would have Denisovan DNA. Reich et al. Am J Hum Gen. 10-7-2011. Epub 1-13. And everyone would have DNA from the new archaic group in Africa. Hammer et al. PNAS. 9-6-2011. Epub 1-6.

  • @n00ffensebut

    I'm afraid you are the ignorant one. Shared ancestry does not imply shared genetics, as mentioned in part 2. Each parent contributes half their alleles, so after 40 generations, ancestral genetics are diluted, and only those alleles coming from very many of your recent ancestors can be preserved.

    We would expect that someone with an MRCA in Europe that was more than 20 or 30 generations to have virtually no chance of carrying a marker that is European biogeography specific.

  • @C0nc0rdance

    If you cannot make it as a biologist, you could always be a contortionist. Now, you are admitting that Eurasians are part Neandertal, despite the fact that you posted a reference about mitochondrial DNA, as if that disproved the mixing. You are claiming that Africans have Neandertal ancestry but not genetics from dilution? If you have no genetic evidence, then all you have is theoretical hocus pocus. Why is it that Neandertal ancestry was not diluted out of Melanesians?

  • @C0nc0rdance

    Melanesians are 4-6% Denisovan and 4% Neandertal. That is 10% of their DNA compared to 0% for Africans.

  • @ForYeensSake Even with "white people refusing to have sex with black people and vice versa", how can anyone know if 6 generations ago, one of your ancestors was black and other 63 were white? You would probably look completely caucasian and even those who refuse to have sex with black people would not refuse you... and their line would be "bucket-chained" with lines of black people.

  • What about Australian aborigines?

  • @Brascofarian damn... answered in pt2! lol

  • What about Australian aborigines?

  • incest.

    nuff said

  • (1)

    Your graphic representation would benefit greatly from a third dimension to account for common ancestors in every generation. It would take the width away from your triangle. and turn it into more of a diamond shape. Better yet why not create a graphic representation for everyone as a whole. Imagine a fire torch, with 7 billion tips of flame working down where the base of the fire meets the handle and the bottom of the torch would be the date of the emergence of homo sapiens.

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  • (2)

    Of course there would be a lot of long slender holes inside the whole shape to account for isolated pockets but those holes would gradually disappear towards the top of the handle IF there is no one alive today who does not share genes with someone, lets say 5000 years ago. The flames themselves will be a really twisted bunch of pathways but all would lead to the individuals alive today at the top. It would definitely take a computer to model but it would take the shape of an Olympic torch.

  • Man, did I do the nasty with a lot of my cousins. :-o

  • Confucius say 'I am your grandaddy'

  • Are you suggesting that I'm related to Nephy? I feel dirty...

  • how do you manage to keep showing me the most beautiful things in our world :)

    thank you so much for this, i guess i won`t be able to avoid the natural sciences much longer :)

    unless of course i enroll in anthropology next...

  • This is pretty interesting considering it's the field i'm majoring in ( Anthropology). Going from the first primitive humans to now is such an interesting study but most people would prefer to hear myths about ancestry rather than scientific knowledge about it.

  • It takes a little bit of cognitive gymnastics to wrap your head around this initially, presumably because you don't typically think about ancestry in this way. It's very, very cool, though!

  • I have tried to understand, but my brain is screaming 'Noooooo'. I would love to have a fascinating multicultural ancestry, but if my ancestors are all bullet-headed Anglo Saxons or Normans or Celts or ancient Britons, how can I have some of Confucius's genes? This is coming from someone who has read 'Seven Daughters of Eve' and 'Blood of the Isles'. Confucius just seems too recent. Maybe you'll explain this in part 2 - I'll stay tuned.

  • I was going to say something but you have a part 2 coming so I'll hold my question until then

  • great stuff can't wait for pt.2 !!

  • I recommend everybody read "The Ancestor's Tale" by Richard Dawkins. it has an eccelent chapter on this very subject ... and much much more.

  • A few years ago someone gave a talk on my campus for something called "Math Across Campus" who talked about how we actually know this mathematically. The discussion after the talk made it pretty clear that most people made the same mistake and didn't catch that it really was "descended from", so don't feel bad. It wasn't your presentation. I think it is just too mind boggling.

  • This is very interesting & mathematically valid. However the UCA should surely be any one of the whole world population that was around at the time of 1400BC (extinct lineages excepted) rather than any one specific person (which makes Adam & Eve true). In other words the whole population at 1400BC is our ancestors. That's why i would suggest that there are many triangles that do not overlap. Everything said here would be just as valid for each individual triangle of several unoverlapping ones.

  • I'm confused. What about Mitochondrial Eve, 50k years back? Why do we have to go back so far? Did that discussion already take place without me?

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  • This is very interesting and mathematically valid. However the UCA should surely be any one of the whole world population that was around at the time of 1400BC (extinct lineages excepted) rather than any one specific person (which makes Adam and Eve true) in other words the whole population at 1400BC is our ancestors. That's why i would suggest that there are many triangles that do not overlap. Everything said here would be just as valid for each individual of several unoverlapping triangles

  • @pilgrimpater said " (which makes Adam and Eve true)"

    Just so you know, Adam and Eve were fictional. Not real, no way no how.

  • @itsasin1969 I know that but such is exactly what creotards would latch on to.

  • When taking all this in - it quickly becomes painfully apparent how much fuzz people make over nothing when it comes to race. So much for "racial purity" huh?

  • I find myself reminded of a Confucious quote ( I think), "under heaven, there is but one family" :) .