Earl Grey

In a previous post, I speculated that that Denisovans might stem from from Homo erectus, at least in part, rather than being a sister group to Neanderthals as suggested in the paper by Reich and Patterson.  It now looks as if this may the case (the in-part bit) : David Reich has said that the Denisovan sample had admixture from Neanderthals and also from an unknown, ultra-archaic population, which might well be erectus.  

Although my conclusion was approximately correct, some of my data was shaky.  I was considering that Ann Gibbons said – “She was not a modern human, but a descendant of Homo erectus, an ancestral species that left Africa almost 2 million years ago. “  Which is mostly wrong, but it might have been the product of misunderstanding something that Reich actually said – maybe his group had already seen signs of that ultra-archaic fraction.  Which is not to slam Gibbons, who is a pretty good reporter.

Other relevant info was more solid.  There are a couple of examples, in Melanesians,  of  archaic alleles of genes in the innate immune system that are very divergent, old enough to have  originated in erectus. Next, we already knew that Denisovan mtDNA  had diverged a long, long time ago, way before the likely date of the split between neanderthals and homo sap.  Lastly, we already knew that modern humans did the deed with Neanderthals, Denisovans, and some archaic group in Africa – surely the ancestors of of the Denisovans got around too.  In other words, admixture with the previous owners was the default hypothesis, to be assumed until proved otherwise.

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This entry was posted in Archaic humans, Denisovans, homo erectus, Neanderthals. Bookmark the permalink.

21 Responses to Earl Grey

  1. That Guy says:

    BTW, speaking of Neanderthals and Denisovans – did you see this article:

    http://www.nature.com/scitable/blog/viruses101/ancient_neanderthal_virus_dna_found

    Some cancers are linked to retroviruses most likely inherited from Neanderthals and/or Denisovans!!!

    This bring up Greg’s theory that living Neanderthals (as in Neanderthal cell-lines) might exist in current humans as cancers…

  2. That Guy says:

    As regards the “ultra-archaic” ancestry, I suspect that it will be linked somehow to the the hominin fossils found in “Red Deer Cave” in Southern China…

  3. dearieme says:

    It’s my cave and I’ll shag who I want to.

    • Richard Sharpe says:

      I was going to suggest that you did not have enough syllables, but given that we have been admonished to be more sensitive about these issues, I won’t supply an alternative.

  4. dave chamberlin says:

    The plot thickens. Simple branching trees of our ancestors has been transformed into braided streams. It wasn’t long ago the experts tenaciously defended the simple out of Africa theory. Then the geneticists had to go get involved and muck it all up. First we were told that we are 1 to 4% Neanderthal. Now we have three more players, the Denisovans, some archaic group form Africa, and (possibly) an ultra archaic group from Asia. It is amazing the wealth of information that comes from a toe bone or a finger bone of an archaic hominid that just happened to die in a very cold cave. Conversely it is frustrating how thoroughly time destroys not just DNA but bones unless the individual died in extraordinary conditions. I wonder (and hope) that archeology will change to scientists in contamination suits vacuuming every cave and location where archaic hominid genes could have been preserved thanks to protection by the permafrost. They would have to be equipped with advanced computers that don’t exist yet but thanks to Craig Venter and others are fast becoming available which rapidly separate and isolate genes and even target their source.
    Excuse me scientists for speculating wildly. I foresee a near future where we have the data to map these braided streams with certainty. I foresee a future (not so near) when we understand how we hybridized to gain an intelligence advantage so great that the beneficiaries spread rapidly. But if we know that, then not only will we know more about our past but then we are a short step from the singularity of fixing stupid. Oh oh, there I go again, dreaming.

  5. john.massey47@gmail.com says:

    May I just please make my perennial plea to avoid terms like “love tryst” and “romantic assignation” when discussing sex with archaics? Ambush pack rape happens distressingly too often among anatomically modern humans. It was standard practice among at least some of the tribes-people in northern Australia, following the judicial application of a sharp rock to enable ease of access. There’s nothing too romantic about a sharp rock applied to someone’s reproductive equipment. It’s stretching credibility to think it didn’t happen 50,000 years ago – in fact it suggests itself to me as one of the likely scenarios that resulted in mixing events. Even one of my very favourite bloggers, John Hawks, recently used the term “hook-ups” – I guess it was a bit more elegant than “fertilisation events” or some such. “did the deed” is kind of neutral, but is still somewhat suggestive of a consensual act. We are adult scientists and engineers – we don’t need to get our knickers in a twist discussing the subject in objective and dispassionate was.

    I did enjoy the “it’s my cave” joke though. I’m not suggesting total loss of humour, just a bit more objectivity and realism about the manner in which these events might have occurred, once we get the funny jokes for the boys out of the way.

    • Richard Sharpe says:

      So, are you suggesting we must apply postmodern politically correct sensibilities to how reproduction was achieved back then?

    • gcochran9 says:

      Obviously it is time for me to put forth my picture of those ancient trysts.

      • Sandgroper says:

        Yes please.

        My guesses at most likely scenarios for AMH/archaic mixes that survived: (1) AMH female raped by one or more archaic males and then released or escapes back to AMH group. Head volume may not have been too different at birth, but different head shape could have caused birthing difficulties. (2) Juvenile archaic female abducted by AMH males, stays with group in exchange for food. (3) Orphaned juvenile archaic female attaches herself to AMH group ditto.

    • Anonymous says:

      I can imagine wife stealing being as important as among modern tribals or Homer’s Aegean, but the offspring resulting from ambush rape between hominins much more different than any two contemporary populations may not have fared very well in times infanticide was a common method of family planning.

      • Gordo says:

        Good point Anon, they were usually killed, especially if different.

        “Ambush pack rape happens distressingly too often among anatomically modern humans.” You talking Chicago, London or Jo’burg Mister Massey?

      • Sandgroper says:

        New Delhi.

      • Sandgroper says:

        Fine. Let’s have a range of whatever the realistic scenarios might have been. I’m just asking that scientists don’t replicate the feeble-minded salacious drivel that turns up in the media every time the subject comes up.
        Whether the kid got bumped off would depend on how ‘normal’ it looked, wouldn’t it? Not all groups made a clear connection about what caused conception.

      • Anonymous says:

        Wife stealing, incorporating females of slain groups, perhaps even the occasional semi-goodish relationships and wife exchanges, maybe in some hominins women left their native group like chimpanzeenas do… I don’t think anybody was as stupid or as unconcerned with paternity as to allow a really different baby much luck, especially if it happened to resemble those hated hominins across the river… On the other hand, maybe they had recessive traits, and maybe they looked (at least to each other) less different than I suppose. I mean, without molecular data, who could tell that Papuans are more related to Koreans than to Blacks, or Blacks more related to Finns than to Bushmen? A bit of topic: I wonder if some phenotypically salient genetic markers could have spread under high paternal uncertainty and infanticide.

    • 420blazeitfgt says:

      >It was standard practice among at least some of the tribes-people in northern Australia, following the judicial application of a sharp rock to enable ease of access.

      Just wondering where you got that from?

  6. TWS says:

    Most were probably some form of captive bride or rape. It might explain why women are physically stimulated by viewing any kind of sex. It is the genetic equivallent of laying back and enjoying it.

  7. j3morecharacters says:

    Sorry for a stupid question, but for me Earl Grey is an bergamot flavored tea. Not google nor the urban dictionary give an interpretation remotely matching with this note. Sir, what am I missing?

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