9 ms·

Oldest human genomes reveal how a small group burst out of Africa

99 points by diodorus 2y ago

eddyzh 2y ago
Makes a huge claim at the start. >"The huge gap between those ages could change our understanding about how humans spread across the world. If the ancestors of today’s non-Africans didn’t sweep across other continents until 47,000 years ago, then those older sites must have been occupied by earlier waves of humans who died off without passing down their DNA to the people now living in places like China and Australia." But at the end gets a bit more balanced >"He Yu, a paleogeneticist at Peking University in Beijing who was not involved in either study, said that the mystery wouldn’t be solved until scientists find DNA in some of the ancient Asian fossils. “We still need early modern human genomes from Asia to really talk about Asia stories,” Dr. Yu said." This puzzle is still missing key elements.
- jl6 2y ago
  It doesn’t seem like an outlandish claim that many waves of humans tried and failed to colonize the world, until one succeeded. I would find it harder to believe that the first to leave Africa got it right first time.
  - h0l0cube 2y ago
    I think the claim is that earlier founders did colonize the world before the final group left and also colonized the world. Land bridges disappeared as the last ice age came to a close, making later attempts more difficult
  - defrost 2y ago
    One question raised by a researcher in the article: Dr. Skoglund also said it would be strange for non-African ancestors to have arisen about 47,000 years ago while modern humans in Asia and Australia dated back 100,000 years. The sites in question could have been incorrectly dated, he said, or people could have reached Asia and Australia that long ago, only to die out. Doesn't mesh well with genetic studies from Australia that show a long history of relatively stable regionalism within Australia (with some still unresolved mixing from Denisovan ancestors. see: (2016) https://www.abc.net.au/news/science/2016-09-22/world-first-study-reveals-rich-history-of-aboriginal-australians/7858376 https://www.abc.net.au/news/science/2016-09-22/world-first-s... (2017) https://www.nature.com/articles/nature21416 https://www.nature.com/articles/nature21416 etc.
    - jltsiren 2y ago
      The actual results in papers like these (both the paper in question and the ones you refer to) are typically of the form: "We sequenced these genomes. Then we took the noisy data, made a lot of assumptions, and applied statistical magic to estimate that the populations split approximately X generations ago. We interpret that as Y years ago." Everything beyond that is interpretation, not the result. Such results are inherently noisy and subject to assumptions. The further back in history you go, the less accurate and reliable the results will be. Ancient DNA comes with its own issues and assumptions, but it helps with the accuracy of the results. Instead of trying to infer something that happened thousands of generations ago, you may now be only hundreds or even tens of generations from the split. The clearest way forward would be sequencing Aboriginal Australian DNA from tens of thousands of years ago. Then you could get a more accurate estimate for the split between that population and other sequenced ancient populations.
      - naijaboiler 2y ago
        my own theory. Depending on cyclical geography limitations, humans have been forever moving out of Africa sporadically, going way back to Neanderthals and possibly even before. It wasn't just one wave, it was multiple waves from time to time. The people that ended up in Australia were some of the earliest anatomically modern humans that successfully made the trip out and for some reason or the other were not really able to colonize Europe/Asia and kept venturing south until they ended up in Australia Other later waves probably made it to the middle east and went back. Some made it a bit into Europe and some of asia. But it wasn't until relatively recent times, that we got waves that finally got a foothold in Europe/Asia and eventually outlasted other homo species that had dominated those areas for a 100,000 years. I am not an anthropologist. I can't prove anything I wrote. I am just using my own common sense and the evidence that has so far been published.
        withinboredom 2y ago
        I wonder if this migrate-and-survive is a "great filter" that organisms must do in order to grow. The same thing will likely happen to space colonists, many will go, but only a few will survive.
  - enkid 2y ago
    I don't think a group of people living somewhere for thousands of years would be "getting it wrong." You're embedding an assumption that evolution has been working toward an end goal of getting humans to spread globally, which isn't how evolution works.
    - jandrese 2y ago
      It doesn't seem all that improbable that humans or close ancestors had colonized other parts of the world for thousands of years only to die off due to climate change/disease/other factors about 40,000 years ago when they had to start all over again. Or maybe the ancestors colonized it and the extinction event was Homo Sapiens out of Africa, although in this case you would expect more DNA mixing. It seems more likely that the ancestors died out for whatever reason and the humans moved into their habitats to refill that ecological niche.
      - enkid 2y ago
        I don't see how you could say that's more likely without evidence, lack significant gaps in archaelogical finds between eras of human presence in a region.
  - shellfishgene 2y ago
    I doubt it's correct to assume groups of humans in Africa one day decided to 'colonize' another place and walked thousands of kilometers to settle down elsewhere. It's probably more like a slow expansion (and reduction) of the settled area, no?
    - airstrike 2y ago
      Both processes could coexist, right? I could see myself waking up one day and saying "what's the farthest we can get to? maybe there are amazing things at the end of the journey"
      - bee_rider 2y ago
        I’m not 100% clear on what the two processes are. In particular, early humans already were pretty mobile. So they’d be going from place to place, hunting as they go. Maybe following some migratory animals. If you got wanderlust, I guess you’d only make it a couple days before you ran out of food, so maybe some dozens of miles, and then you are back to doing typical human stuff, right?
        withinboredom 2y ago
        it can also be stupid politics/religion: "your village is the reason for our famine, your entire village is banned from here. you will walk until you see the mountains and until you no longer see them behind you" ... next thing you know, you're in europe or asia.
        miniwark 2y ago
        They where all nomadics, so the concept of a village did not exist yet. It was more like family related moving groups, or maybe "clans". That said, at an individual level there was probably a concept of people exchange when meeting another group, or banning of an individual.
        2y ago
  - tetris11 2y ago
    I think they just walked to other places as and when the climate changed. Some adapted and stayed, others moved the greener pastures. This slow and climate-driven process can hardly be described as colonization.
  - mapt 2y ago
    It doesn't seem like an outlandish possibility. That's distinct from making a claim, an assertion with supporting evidence. To make a claim, we would want evidence, and the evidence here would be a genetic isolation (lack of chronological overlap, synonymous with lack of interbreeding) of ancient Asian humans from ancient African humans. This requires sequencing a lot of ancient Asian DNA, which seems not to have happened yet. We barely have a cohesive evidence supported grasp of Neanderthal interactions in Europe, but are gradually updating to support more and more absorption by interbreeding.
  - kspacewalk2 2y ago
    And their failure doesn't mean they're completely absent from our genome.
- miniwark 2y ago
  The view of the chinese researcher is in line with the Multiregional origin hypothesis of modern humans, where asian humans may partially come from asia. So his reply is not surprising. https://en.wikipedia.org/wiki/Multiregional_origin_of_modern_humans https://en.wikipedia.org/wiki/Multiregional_origin_of_modern... Instead, the article follow the Out of Africa origin, and therefore did not explain the old chineses and autralian remains. The article try to explain this by saying than it's because this lines where extincts or than the dates are wrong, but this explanations are not very convincing.
  - InDubioProRubio 2y ago
    [flagged]
    - trallnag 2y ago
      What place do Europeans take in these museums? Elves?
    - deleted 2y ago
      [deleted]
    - Loughla 2y ago
      Bingo. Nearly every time you see a special carve out for the ancient ancestors of any particular country that is wildly contrary to established theories, it's less science and more politics. This just happens to be China this time, instead of European countries.
  - bee_rider 2y ago
    What’s the most significant difference between the theories? The Wikipedia article says: > “The primary competing scientific hypothesis is currently recent African origin of modern humans, which proposes that modern humans arose as a new species in Africa around 100-200,000 years ago, moving out of Africa around 50-60,000 years ago to replace existing human species such as Homo erectus and the Neanderthals without interbreeding.[5][6][7][8] This differs from the multiregional hypothesis in that the multiregional model predicts interbreeding with preexisting local human populations in any such migration.” But it is a somewhat weird quote in the Wikipedia article. They’ve got the whole thing in quotes with multiple citations (so it isn’t clear which citation the quote comes from), it isn’t attributed to anybody in particular, and it doesn’t seem to be a very accurate description of what I though the consensus was, at least. (It is widely believed that humans interbred with other hominids, right?)
- PittleyDunkin 2y ago
  Am I missing something? Surely Europe is the same continent as Asia. Why wouldn't people just walk over? It seems reasonable to assume that if evidence exists on one side of the continent that it'd imply existence on the other side, too. If anything you'd need a theory why they failed to spread to formulate interesting discussion!
  - hackinthebochs 2y ago
    The Steppes are a natural barrier between East and West until the point where technology caught up to make it passable.
    - PittleyDunkin 2y ago
      Well we have human ancestors on both sides of that barrier, so clearly it's not insurmountable in absolute terms, either from taking the souther route or migrating with herds or some other thing I haven't thought about (I'm not sure waterways would get you the whole way, but it'd get you from the urals to either side). The question is why this would pose a barrier to some populations and not others. EDIT: also, I forgot that a lot of the steppe is forested. Surely that would make it significantly less of a barrier.
      - hackinthebochs 2y ago
        No terrain is insurmountable considering chance and a hundred thousand years. The question is how likely will any given group be able to pass through and flourish on the other side? We have many examples of isolated human populations on islands or across inhospitable barriers that it shouldn't be surprising to find isolated populations on either side of the Eurasian continent. Off the top of my head, Australian aboriginals, the Andamanese and New Guinea islanders are examples of isolated populations with essentially no gene flow between larger populations over 10s of thousands of years. Even the fact that we talk about how many populations ultimately left Africa in prehistory implies there must have been some barrier to overcome. > also, I forgot that a lot of the steppe is forested. Surely that would make it significantly less of a barrier. Also consider the ice age and how that affected the degree to which Eurasia was hospitable.
verisimi 2y ago
Such fictional assumptions... > Some 45,000 years ago, a tiny group of people — fewer than 1,000, all told — wandered the icy northern fringes of Europe. Is it not possible that: Some 45,000 years ago, a tiny group of people — fewer than 1,000, all told — wandered from sunny Australia into China, eventually reaching Africa and Europe? It is impossible to tell the direction of travel.
- reedf1 2y ago
  It is not really up for debate. Haplogroups provide direct lineage and evidence for migration.
- pvg 2y ago
  Is it not possible that: You'd be able to look for and find some evidence of their ancestors in Australia and you don't. But there's plenty of it in Africa.
  - Mountain_Skies 2y ago
    That assumes all evidence is equally easy to find and has been equally searched for.
    - pvg 2y ago
      Sort of but we're not talking about apes and monkeys here, it's placental mammals in general. So the evidence is overwhelming https://en.wikipedia.org/wiki/Mammals_of_Australia#Evolutionary_history https://en.wikipedia.org/wiki/Mammals_of_Australia#Evolution... If we got this wrong, most of paleontology is unreliable.
  - pfannkuchen 2y ago
    Africa is a static large site of habitation where the disappearance of 99% of evidence would still leave easily findable evidence. In GP’s scenario the habitation would be transient. Not really comparable.
- madaxe_again 2y ago
vixen99 2y ago
Thank you!
- dang 2y ago
  We detached this comment from https://news.ycombinator.com/item?id=42430565 https://news.ycombinator.com/item?id=42430565 - your comment is just fine, there's nothing wrong with posting 'thank you'! But I wanted to pin the other link to the top, where real estate is expensive.
InfiniteLoup 2y ago
Would any evidence that contradicts the 'Out-of-Africa' dogma even get considered by Western scientists?
- AndrewDucker 2y ago
  Sure! If you've encountered some then please share!
  - InfiniteLoup 2y ago
    [flagged]
    - AndrewDucker 2y ago
      Nope! I'm just interested in what a fellow HNer has found, if they're interested in sharing. That's why I have discussions on HN, so I can learn from others with more knowledge than me!
    - zarzavat 2y ago
      Even if your theory is correct that the entire academic establishment in the US is conspiring to mislead people, how do you explain research outside the US?
    - Hikikomori 2y ago
      Just going to leave us hanging and not share your forbidden knowledge?
    - ripped_britches 2y ago
      Out of Africa way predates DEI. Are you saying this is a 1980s conspiracy?
      - zo1 2y ago
        [flagged]
zoombippy 2y ago
This doesn't account for shrinkage in the pool
erichocean 2y ago
It's amazing how out of date this conception is with the actual research. I guess it's to be expected that pop-sci is 10-15 years behind…
robwwilliams 2y ago
One error in this article by Zimmer that surprises me. He claims all modern humans have some admixture with Neaderthals but to the best of my knowledge this is not true of KhoiSan, Central African hunter gatherers, and several West African populations. Does Zimmer know something that I do not? Or David Reich?
- mmmrtl 2y ago
  Hasn't backmigration/Eurasian admixture post-introgression made that true? iirc reference bias artefactually made African genomes look like they had no Neanderthal segments. https://www.cell.com/cell/fulltext/S0092-8674(20)30059-3 https://www.cell.com/cell/fulltext/S0092-8674(20)30059-3 https://www.pnas.org/doi/full/10.1073/pnas.1313787111 https://www.pnas.org/doi/full/10.1073/pnas.1313787111
  - robwwilliams 2y ago
    Lovely paper but their analysis did not include either KhoiSan or Central African hunter-gather Pygmy populations. They used the 1000 Genomes project.
    - robwwilliams 2y ago
      I read a bit more. There definitely was introgression of West Eurasian populations into East Africa and Sudan than percolated into West Africans to the tune of about 15 million base-pairs of sequence tagged as Neanderthal. Not sure we have values for how much Yoruban ancestry is now embedded in Mbuti genomes, but it is small. So the flow of Neanderthal genomes into Central African hunter-gathers will sub-decimal dust. But having said all that, maybe the key point Zimmer is making IS a good generalization.
      - mmmrtl 2y ago
        I think it is a fair generalization at this point. Mbuti also have a ~6% West Eurasian admixture signal using an ancient (4.5kya) Ethiopian individual as reference, though Pickrell 2014 did not see it. Decimal dust, perhaps? https://www.science.org/doi/10.1126/science.aad2879 https://www.science.org/doi/10.1126/science.aad2879 The ghost admixture story(s) will turn out to be much more localized, I imagine.
The-Old-Hacker 2y ago
https://archive.ph/WLcdD https://archive.ph/WLcdD

99 points by diodorus 2y ago

Makes a huge claim at the start. >"The huge gap between those ages could change our understanding about how humans spread across the world. If the ancestors of today’s non-Africans didn’t sweep across other continents until 47,000 years ago, then those older sites must have been occupied by earlier waves of humans who died off without passing down their DNA to the people now living in places like China and Australia." But at the end gets a bit more balanced >"He Yu, a paleogeneticist at Peking University in Beijing who was not involved in either study, said that the mystery wouldn’t be solved until scientists find DNA in some of the ancient Asian fossils. “We still need early modern human genomes from Asia to really talk about Asia stories,” Dr. Yu said." This puzzle is still missing key elements.

jl6 2y ago
It doesn’t seem like an outlandish claim that many waves of humans tried and failed to colonize the world, until one succeeded. I would find it harder to believe that the first to leave Africa got it right first time.
- h0l0cube 2y ago
  I think the claim is that earlier founders did colonize the world before the final group left and also colonized the world. Land bridges disappeared as the last ice age came to a close, making later attempts more difficult
- defrost 2y ago
  One question raised by a researcher in the article: Dr. Skoglund also said it would be strange for non-African ancestors to have arisen about 47,000 years ago while modern humans in Asia and Australia dated back 100,000 years. The sites in question could have been incorrectly dated, he said, or people could have reached Asia and Australia that long ago, only to die out. Doesn't mesh well with genetic studies from Australia that show a long history of relatively stable regionalism within Australia (with some still unresolved mixing from Denisovan ancestors. see: (2016) https://www.abc.net.au/news/science/2016-09-22/world-first-study-reveals-rich-history-of-aboriginal-australians/7858376 https://www.abc.net.au/news/science/2016-09-22/world-first-s... (2017) https://www.nature.com/articles/nature21416 https://www.nature.com/articles/nature21416 etc.
  - jltsiren 2y ago
    The actual results in papers like these (both the paper in question and the ones you refer to) are typically of the form: "We sequenced these genomes. Then we took the noisy data, made a lot of assumptions, and applied statistical magic to estimate that the populations split approximately X generations ago. We interpret that as Y years ago." Everything beyond that is interpretation, not the result. Such results are inherently noisy and subject to assumptions. The further back in history you go, the less accurate and reliable the results will be. Ancient DNA comes with its own issues and assumptions, but it helps with the accuracy of the results. Instead of trying to infer something that happened thousands of generations ago, you may now be only hundreds or even tens of generations from the split. The clearest way forward would be sequencing Aboriginal Australian DNA from tens of thousands of years ago. Then you could get a more accurate estimate for the split between that population and other sequenced ancient populations.
    - naijaboiler 2y ago
      my own theory. Depending on cyclical geography limitations, humans have been forever moving out of Africa sporadically, going way back to Neanderthals and possibly even before. It wasn't just one wave, it was multiple waves from time to time. The people that ended up in Australia were some of the earliest anatomically modern humans that successfully made the trip out and for some reason or the other were not really able to colonize Europe/Asia and kept venturing south until they ended up in Australia Other later waves probably made it to the middle east and went back. Some made it a bit into Europe and some of asia. But it wasn't until relatively recent times, that we got waves that finally got a foothold in Europe/Asia and eventually outlasted other homo species that had dominated those areas for a 100,000 years. I am not an anthropologist. I can't prove anything I wrote. I am just using my own common sense and the evidence that has so far been published.
      - withinboredom 2y ago
        I wonder if this migrate-and-survive is a "great filter" that organisms must do in order to grow. The same thing will likely happen to space colonists, many will go, but only a few will survive.
- enkid 2y ago
  I don't think a group of people living somewhere for thousands of years would be "getting it wrong." You're embedding an assumption that evolution has been working toward an end goal of getting humans to spread globally, which isn't how evolution works.
  - jandrese 2y ago
    It doesn't seem all that improbable that humans or close ancestors had colonized other parts of the world for thousands of years only to die off due to climate change/disease/other factors about 40,000 years ago when they had to start all over again. Or maybe the ancestors colonized it and the extinction event was Homo Sapiens out of Africa, although in this case you would expect more DNA mixing. It seems more likely that the ancestors died out for whatever reason and the humans moved into their habitats to refill that ecological niche.
    - enkid 2y ago
      I don't see how you could say that's more likely without evidence, lack significant gaps in archaelogical finds between eras of human presence in a region.
- shellfishgene 2y ago
  I doubt it's correct to assume groups of humans in Africa one day decided to 'colonize' another place and walked thousands of kilometers to settle down elsewhere. It's probably more like a slow expansion (and reduction) of the settled area, no?
  - airstrike 2y ago
    Both processes could coexist, right? I could see myself waking up one day and saying "what's the farthest we can get to? maybe there are amazing things at the end of the journey"
    - bee_rider 2y ago
      I’m not 100% clear on what the two processes are. In particular, early humans already were pretty mobile. So they’d be going from place to place, hunting as they go. Maybe following some migratory animals. If you got wanderlust, I guess you’d only make it a couple days before you ran out of food, so maybe some dozens of miles, and then you are back to doing typical human stuff, right?
      - withinboredom 2y ago
        it can also be stupid politics/religion: "your village is the reason for our famine, your entire village is banned from here. you will walk until you see the mountains and until you no longer see them behind you" ... next thing you know, you're in europe or asia.
        miniwark 2y ago
        They where all nomadics, so the concept of a village did not exist yet. It was more like family related moving groups, or maybe "clans". That said, at an individual level there was probably a concept of people exchange when meeting another group, or banning of an individual.
        2y ago
- tetris11 2y ago
  I think they just walked to other places as and when the climate changed. Some adapted and stayed, others moved the greener pastures. This slow and climate-driven process can hardly be described as colonization.
- mapt 2y ago
  It doesn't seem like an outlandish possibility. That's distinct from making a claim, an assertion with supporting evidence. To make a claim, we would want evidence, and the evidence here would be a genetic isolation (lack of chronological overlap, synonymous with lack of interbreeding) of ancient Asian humans from ancient African humans. This requires sequencing a lot of ancient Asian DNA, which seems not to have happened yet. We barely have a cohesive evidence supported grasp of Neanderthal interactions in Europe, but are gradually updating to support more and more absorption by interbreeding.
- kspacewalk2 2y ago
  And their failure doesn't mean they're completely absent from our genome.
miniwark 2y ago
The view of the chinese researcher is in line with the Multiregional origin hypothesis of modern humans, where asian humans may partially come from asia. So his reply is not surprising. https://en.wikipedia.org/wiki/Multiregional_origin_of_modern_humans https://en.wikipedia.org/wiki/Multiregional_origin_of_modern... Instead, the article follow the Out of Africa origin, and therefore did not explain the old chineses and autralian remains. The article try to explain this by saying than it's because this lines where extincts or than the dates are wrong, but this explanations are not very convincing.
- InDubioProRubio 2y ago
  [flagged]
  - trallnag 2y ago
    What place do Europeans take in these museums? Elves?
  - deleted 2y ago
    [deleted]
  - Loughla 2y ago
    Bingo. Nearly every time you see a special carve out for the ancient ancestors of any particular country that is wildly contrary to established theories, it's less science and more politics. This just happens to be China this time, instead of European countries.
- bee_rider 2y ago
  What’s the most significant difference between the theories? The Wikipedia article says: > “The primary competing scientific hypothesis is currently recent African origin of modern humans, which proposes that modern humans arose as a new species in Africa around 100-200,000 years ago, moving out of Africa around 50-60,000 years ago to replace existing human species such as Homo erectus and the Neanderthals without interbreeding.[5][6][7][8] This differs from the multiregional hypothesis in that the multiregional model predicts interbreeding with preexisting local human populations in any such migration.” But it is a somewhat weird quote in the Wikipedia article. They’ve got the whole thing in quotes with multiple citations (so it isn’t clear which citation the quote comes from), it isn’t attributed to anybody in particular, and it doesn’t seem to be a very accurate description of what I though the consensus was, at least. (It is widely believed that humans interbred with other hominids, right?)
PittleyDunkin 2y ago
Am I missing something? Surely Europe is the same continent as Asia. Why wouldn't people just walk over? It seems reasonable to assume that if evidence exists on one side of the continent that it'd imply existence on the other side, too. If anything you'd need a theory why they failed to spread to formulate interesting discussion!
- hackinthebochs 2y ago
  The Steppes are a natural barrier between East and West until the point where technology caught up to make it passable.
  - PittleyDunkin 2y ago
    Well we have human ancestors on both sides of that barrier, so clearly it's not insurmountable in absolute terms, either from taking the souther route or migrating with herds or some other thing I haven't thought about (I'm not sure waterways would get you the whole way, but it'd get you from the urals to either side). The question is why this would pose a barrier to some populations and not others. EDIT: also, I forgot that a lot of the steppe is forested. Surely that would make it significantly less of a barrier.
    - hackinthebochs 2y ago
      No terrain is insurmountable considering chance and a hundred thousand years. The question is how likely will any given group be able to pass through and flourish on the other side? We have many examples of isolated human populations on islands or across inhospitable barriers that it shouldn't be surprising to find isolated populations on either side of the Eurasian continent. Off the top of my head, Australian aboriginals, the Andamanese and New Guinea islanders are examples of isolated populations with essentially no gene flow between larger populations over 10s of thousands of years. Even the fact that we talk about how many populations ultimately left Africa in prehistory implies there must have been some barrier to overcome. > also, I forgot that a lot of the steppe is forested. Surely that would make it significantly less of a barrier. Also consider the ice age and how that affected the degree to which Eurasia was hospitable.

verisimi 2y ago

Such fictional assumptions... > Some 45,000 years ago, a tiny group of people — fewer than 1,000, all told — wandered the icy northern fringes of Europe. Is it not possible that: Some 45,000 years ago, a tiny group of people — fewer than 1,000, all told — wandered from sunny Australia into China, eventually reaching Africa and Europe? It is impossible to tell the direction of travel.

reedf1 2y ago
It is not really up for debate. Haplogroups provide direct lineage and evidence for migration.
pvg 2y ago
Is it not possible that: You'd be able to look for and find some evidence of their ancestors in Australia and you don't. But there's plenty of it in Africa.
- Mountain_Skies 2y ago
  That assumes all evidence is equally easy to find and has been equally searched for.
  - pvg 2y ago
    Sort of but we're not talking about apes and monkeys here, it's placental mammals in general. So the evidence is overwhelming https://en.wikipedia.org/wiki/Mammals_of_Australia#Evolutionary_history https://en.wikipedia.org/wiki/Mammals_of_Australia#Evolution... If we got this wrong, most of paleontology is unreliable.
- pfannkuchen 2y ago
  Africa is a static large site of habitation where the disappearance of 99% of evidence would still leave easily findable evidence. In GP’s scenario the habitation would be transient. Not really comparable.
madaxe_again 2y ago

vixen99 2y ago

Thank you!

dang 2y ago
We detached this comment from https://news.ycombinator.com/item?id=42430565 https://news.ycombinator.com/item?id=42430565 - your comment is just fine, there's nothing wrong with posting 'thank you'! But I wanted to pin the other link to the top, where real estate is expensive.

InfiniteLoup 2y ago

Would any evidence that contradicts the 'Out-of-Africa' dogma even get considered by Western scientists?

AndrewDucker 2y ago
Sure! If you've encountered some then please share!
- InfiniteLoup 2y ago
  [flagged]
  - AndrewDucker 2y ago
    Nope! I'm just interested in what a fellow HNer has found, if they're interested in sharing. That's why I have discussions on HN, so I can learn from others with more knowledge than me!
  - zarzavat 2y ago
    Even if your theory is correct that the entire academic establishment in the US is conspiring to mislead people, how do you explain research outside the US?
  - Hikikomori 2y ago
    Just going to leave us hanging and not share your forbidden knowledge?
  - ripped_britches 2y ago
    Out of Africa way predates DEI. Are you saying this is a 1980s conspiracy?
    - zo1 2y ago
      [flagged]

zoombippy 2y ago

This doesn't account for shrinkage in the pool

erichocean 2y ago

It's amazing how out of date this conception is with the actual research. I guess it's to be expected that pop-sci is 10-15 years behind…

robwwilliams 2y ago

One error in this article by Zimmer that surprises me. He claims all modern humans have some admixture with Neaderthals but to the best of my knowledge this is not true of KhoiSan, Central African hunter gatherers, and several West African populations. Does Zimmer know something that I do not? Or David Reich?

mmmrtl 2y ago
Hasn't backmigration/Eurasian admixture post-introgression made that true? iirc reference bias artefactually made African genomes look like they had no Neanderthal segments. https://www.cell.com/cell/fulltext/S0092-8674(20)30059-3 https://www.cell.com/cell/fulltext/S0092-8674(20)30059-3 https://www.pnas.org/doi/full/10.1073/pnas.1313787111 https://www.pnas.org/doi/full/10.1073/pnas.1313787111
- robwwilliams 2y ago
  Lovely paper but their analysis did not include either KhoiSan or Central African hunter-gather Pygmy populations. They used the 1000 Genomes project.
  - robwwilliams 2y ago
    I read a bit more. There definitely was introgression of West Eurasian populations into East Africa and Sudan than percolated into West Africans to the tune of about 15 million base-pairs of sequence tagged as Neanderthal. Not sure we have values for how much Yoruban ancestry is now embedded in Mbuti genomes, but it is small. So the flow of Neanderthal genomes into Central African hunter-gathers will sub-decimal dust. But having said all that, maybe the key point Zimmer is making IS a good generalization.
    - mmmrtl 2y ago
      I think it is a fair generalization at this point. Mbuti also have a ~6% West Eurasian admixture signal using an ancient (4.5kya) Ethiopian individual as reference, though Pickrell 2014 did not see it. Decimal dust, perhaps? https://www.science.org/doi/10.1126/science.aad2879 https://www.science.org/doi/10.1126/science.aad2879 The ghost admixture story(s) will turn out to be much more localized, I imagine.

The-Old-Hacker 2y ago

https://archive.ph/WLcdD https://archive.ph/WLcdD