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  1. 26 Jun '10 04:57 / 1 edit
    from Debates, Thread 131542, "the ancient human diaspora", OP.

    from Thread 131389, "General Stanley McChrystal's take on Obama", p. 7.

    actually, the Uzbek refugees seen on TV recently seem quite oriental, re their eyes. some of them could be mistaken for Chinese.

    Patton was pre-web and had a different worldview. still, he may have been somewhat correct. the Russians, Hungarians, etc. were remainders of the eastern wave of the Hun tsunami.

    saw the tail end of an interesting show on public tv last night. "Journey of Man". outdated (2003) but still ahead of what i've read. the narrator was also the lead scientist (i think). the common point of ancestry for asians, europeans, and native americans is in the middle of central asia; one of the waves from africa split up there. the split was 40,000 years ago, represented by one mutational marker from a single ancestor (the marker shows up in all the above populations). out of 2000 blood samples taken by the author's program in central america, one showed a direct descendant of the 40,000-y-o ancestor. the author traveled to meet him (and scared the bejesus out of the descendent because he thought the "doctor" coming to see him was going to tell him he had cancer). also remembered from the show that the reason europeans are so different from everyone else in the world (red/blond/brunette hair, different faces etc.) was that they travelled there prior to the last ice age and were cut off from the rest of the world.

    here is the wiki for the book, which doesn't mention the movie made from the book. and for the author. looks like he gained some weight. and the wiki for the author points to a youtube copy of the movie. no wiki for the movie.

    http://en.wikipedia.org/wiki/Journey_of_Man

    http://en.wikipedia.org/wiki/Spencer_Wells

    http://www.youtube.com/watch?v=OV6A8oGtPc4&feature=PlayList&p=26D4689DBF14F73D&index=0
  2. 26 Jun '10 04:57
    i'm wondering about that "cut off from the world" bit. i'm thinking that implies either a collection of mutations that just happened to occur in Europe and nowhere else, or that the rest of the world were contacting each other (in the family way) a lot more than is generally believed.
  3. 26 Jun '10 04:58
    in debates i'm asking for debate topics re the OP. here i don't care.
  4. 26 Jun '10 14:41
    Originally posted by zeeblebot
    out of 2000 blood samples taken by the author's program in central america, one showed a direct descendant of the 40,000-y-o ancestor.
    I don't understand that bit. Is this a direct decedent from a bone we have found that has DNA?
    Or is it as implied by your post, a direct descendant from someone whose DNA mutated in a certain way that is visible in certain races - who are all his 'direct descendants'. If it is the latter then what was special about this one man?
  5. 26 Jun '10 18:12
    Originally posted by twhitehead
    I don't understand that bit. Is this a direct decedent from a bone we have found that has DNA?
    Or is it as implied by your post, a direct descendant from someone whose DNA mutated in a certain way that is visible in certain races - who are all his 'direct descendants'. If it is the latter then what was special about this one man?
    the second.

    i don't get why the guy is special. i guess this particular mutation marker shows up in all the listed populations, so they can track the populations. but this is the only guy in the neighborhood of the split who had the marker out of the 2000 samples taken (a multi-nation sample, i think).
  6. 26 Jun '10 18:13 / 1 edit
    maybe he was the only descendant who stayed in the local neighborhood (the only one found in the samples).
  7. 26 Jun '10 20:35
    Originally posted by zeeblebot
    the second.

    i don't get why the guy is special. i guess this particular mutation marker shows up in all the listed populations, so they can track the populations. but this is the only guy in the neighborhood of the split who had the marker out of the 2000 samples taken (a multi-nation sample, i think).
    That makes no sense at all.
    If he is the only person in the sample with the mutation, then who found out about the marker in the first place? Is it from some other study?
    How was the 'neighborhood' of the split known if very few descendants hung around?
  8. 26 Jun '10 23:12
    they didn't discover the marker in this guy. they discovered it earlier in all the list populations and tracked it back somehow to this guy.

    i had the same kind of questions re how did they know the split was in central asia. wiki is not providing the answers.

    also, if they're just looking at the one marker and it doesn't show up in everyone in the populations, how do they know that's the only wave? the millions-of-old skeletons in china could still be ancestors of people in china. the wave that the 40,000-y-o ancestor came from might just be an overlay adding to those people, not a replacement for them.

    an interesting link re Neanderthal genes in modern humans:

    http://sciblogs.co.nz/the-atavism/2010/06/08/if-some-of-us-have-neanderthal-genes-are-neanderthals-us/
  9. 28 Jun '10 11:39
    I have started watching it, and the narrator is not making sense. He seems to be saying that the San people are our ancestors, when in reality this is not the case at all. In reality, we are both descended from the same ancestors. Our common ancestor was no more San than he was European or Chinese.
  10. Subscriber AThousandYoung
    Do ya think?
    28 Jun '10 16:06 / 3 edits
    Originally posted by twhitehead
    I have started watching it, and the narrator is not making sense. He seems to be saying that the San people are our ancestors, when in reality this is not the case at all. In reality, we are both descended from the same ancestors. Our common ancestor was no more San than he was European or Chinese.
    Our common ancestor was Sandawe. Since they didn't change their environment they didn't need to change their biology or culture. However it has evolved over the years due to simple random drift if nothing else.

    http://en.wikipedia.org/wiki/Sandawe_people
  11. 28 Jun '10 18:57
    Originally posted by AThousandYoung
    Our common ancestor was Sandawe. Since they didn't change their environment they didn't need to change their biology or culture. However it has evolved over the years due to simple random drift if nothing else.

    http://en.wikipedia.org/wiki/Sandawe_people
    And that is the kind of thinking that I am objecting to, and which seems to be a common mistake throughout the Journey of Man film.
    The mutations being studied happen at a fairly regular rate throughout all populations.
    If we are all descended from a common ancestor then we are all one people, to claim that our common ancestor was Sandawe, European, Chinese, etc is just nonsense. Sure the Sandawe might be the closest physically, culturally or even genetically to our common ancestor, but that does not make our common ancestor Sandawe.
    Worse, the genetic evidence does not indicate that the Sandawe the closest genetically to our common ancestor.
    They are our most distant cousins. The rest of us share more recent common ancestors.

    I also found the Journey of Man movie making some other shoddy science mistakes. He went to India and found a marker also found in aborigines and concluded from this one mutation that the man was descended from the ancestors of the aborigines as they made their way to Australia. That is bad science. There could be numerous other explanations. What would be required to prove his case would be some aboriginy markers as well as some other markers that did not occur in the aborigines.