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Comment by AlotOfReading | Hacker News Reader

All the evidence we have points to the vast, vast majority (>90%) of non-african human ancestry originating from hominin populations that were in Africa around 60-80k years ago, and were anatomically modern about 300k years ago. This article is about an ancestral clade of archaic hominins that contributed around 2% of modern non-african ancestry globally, that we've known about for years.

OOA (with minor admixture) is the consensus position for a lot of excellent reasons.

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there were multiple out of africa migrations and backmigration into Africa, 60-80k is just the most recent and the prominent founder population for modern humans outside of Africa.

> OOA (with minor admixture) is the consensus position for a lot of excellent reasons

It isn't really. Serious historians and geneticists take great issue with it.

It's only really the pop-anthropologists (the non-rigorous social science ones) who think OOA is a settled issue.

You're going to have to explain this one. The only thing I can figure is that you're making a distinction about "traditional" RAO vs modern hybridization models, but my comment already mentions those (albeit indirectly, given that I'm writing to an audience).

But if you're genuinely trying to say that the broad strokes out of africa model isn't consensus, I have no idea what you're talking about. Just to make sure I haven't missed some momentous event since the last time I was doing fieldwork, I even checked some unpublished books, review papers, and actual research. They all talk about OOA as completely settled or instead simply assume it.

Is this like a CAS thing? Truly baffled.

OOA is extremely problematic. Lots of hoops are needed to make it work - a double exodus from Africa and a population bottleneck, etc. None of these hoops are needed if we just let go and assume a Middle Eastern origin for homo sapiens.

Basically the only reason a Kuhnian paradigm shift isn't happening is because of American politics; OOA is needed to debunk some stupid 19th century American racial theories. (Theories that the rest of the world doesn't even know or care about.)

But where’s the evidence? I haven’t heard Reich or Paäbo go about this.

A middle eastern origin presents obvious problems explaining the genetic diversity data and the serial founder effects we observe globally. These naturally fall out of African origin, whereas a middle eastern origin needs a back to Africa that somehow avoids founder effects.

Which stupid racial theories do you think African origin is trying to debunk and why would the many European researchers working on human origins care?

It is also the consensus position for a lot of bad reasons though.

There is an assumption that belief in, or even reasonable agnosticism towards, any other theory can only be motivated by racism.

There are many people that believe OOA because they want to believe it, because they want to believe we are all more similar than we are different, etc.

Multiregional hypotheses are perfectly plausible. We have very limited information one way or another. Out of Africa may be more likely but it is far from certain.

There are many people that believe OOA because they want to believe it

But, also, There are many people that [do not] believe OOA because they [do not] want to believe it.

That's why we look at genetic evidence, to eliminate nonsense. That evidence strongly points to chimps, gorillas, humans etc all coming from the same place.

If it makes you feels better, think of it this way:

we don't believe OOA because the evidence says we're related to blacks. We believe it because the evidence says we're pretty much hairless apes. (And a lot of us aren't even hairless!)

There, feel better about it now?

theres actually almost zero clarity around the common ancestor between apes and humans, and a lot of speculation that the common ancestor lived 6-8 million years ago.

> That evidence strongly points to chimps, gorillas, humans etc all coming from the same place.

No. Non-African humans have genetic lineages that do not occur anywhere in Africa.

This doesn't mean OOA is necessarily false, but does makes it much less likely.

Also, lumping in primates is a red herring. The resolution of our gene clade knowledge doesn't go that far back. Dreaming about some hypothetical ape ancestor is a vibe, not a science.

Just to be clear about what the term multiregionalism means, it's an argument that there's anatomical continuity between archaic hominin populations around afroeurasia and modern human populations. That is, anatomical modernity didn't evolve once in Africa, but multiple times all over the world in populations that are still extant today. A multiregional hypothesis might say that modern Chinese people evolved from archaic populations in Asia.

This is completely and unequivocally rejected by the genetic evidence. The evidence is so absolutely overwhelming that even fucking Wolpoff came around and now says:

    It is broadly agreed that all recent/living human populations ultimately descend from Africans.

Now, if you mean something completely different to the commonly understood definition of multiregionalism, I'm willing to hear it.

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