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Does this study nullifies the african origin hypthesis?

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  • Does this study nullifies the african origin hypthesis?

    Can someone please explain the impact of this study on the genographic project?

    http://www.sciencedaily.com/releases...0209184558.htm

  • #2
    Originally posted by haider
    Can someone please explain the impact of this study on the genographic project?

    http://www.sciencedaily.com/releases...0209184558.htm
    Three original African migrations dated very old.
    One Asian back migration to Europe afterward.
    Migration from S. Europe to N. Europe even later.
    Replacement theory discredited.

    No idea about the genographic project.

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    • #3
      Originally posted by haider
      Can someone please explain the impact of this study on the genographic project?

      http://www.sciencedaily.com/releases...0209184558.htm
      I like the word "trellis," still it might be premature to debunk the family tree as was done with Aristotle's ladder. Simply speaking, species can interbreed with species, and no one knows what happened to the ancient humans. We just assume hunter-gathers began modern ancient tribal vicious conflicts.

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      • #4
        Originally posted by GregKiroKH
        I like the word "trellis," still it might be premature to debunk the family tree as was done with Aristotle's ladder. Simply speaking, species can interbreed with species, and no one knows what happened to the ancient humans. We just assume hunter-gathers began modern ancient tribal vicious conflicts.
        That's really interesting. I always thought that one specie cannot interbreed with another. That's what make them a different specie.

        My understanding was from the behavior of the primates. Human can't interbreed with Camps, Champs can't with Apes, and so on.

        Although I agree that the tree relationship would still hold. Despite of all the interbreeing we may still be descendant of one couple in Africa.

        Haider

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        • #5
          The impact has no real affect does it? there were people around 700,000 years ago in England if the latest finds of Black Flint tools holds up. These humans would have been other human types? why not earlier?

          What if our twig of humanity spread from Eurasia to east, west, and south eliminating all others. Over time our isolated groups do the evolution thing.

          Not everyone came out of Africa in 3 waves. There had to have been people continuously on the move in and out of Africa in search of safety and food.

          Couldn't our ancestor left Africa 200,000 years ago.? no one is saying they were the only people or the only races of that time.

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          • #6
            Originally posted by haider
            That's really interesting. I always thought that one specie cannot interbreed with another. That's what make them a different specie.

            My understanding was from the behavior of the primates. Human can't interbreed with Camps, Champs can't with Apes, and so on.

            Although I agree that the tree relationship would still hold. Despite of all the interbreeing we may still be descendant of one couple in Africa.

            Haider
            Yep, a species is a group of organisms that can interbreed in nature to produce a fertile offspring.

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            • #7
              All of this may be proven true, but it doesn't change the fact that all y-DNA & mtDNA are of recent African origin. If the populations did interbreed, the y-DNA & mtDNA of the archaics was eliminated through genetic drift.

              I don't have any source to cite, but it seems I have heard that Alan Templeton has for years been strongly opposed to the Out of Africa theory. Before jumping to conclusions, I think it is important to let actual scientists who advocate Out of Africa offer peer reviews to this work.

              Timothy Peterman

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              • #8
                Originally posted by T E Peterman
                All of this may be proven true, but it doesn't change the fact that all y-DNA & mtDNA are of recent African origin. If the populations did interbreed, the y-DNA & mtDNA of the archaics was eliminated through genetic drift.

                I don't have any source to cite, but it seems I have heard that Alan Templeton has for years been strongly opposed to the Out of Africa theory. Before jumping to conclusions, I think it is important to let actual scientists who advocate Out of Africa offer peer reviews to this work.

                Timothy Peterman

                Yes. Of course. But if it is true it does change the fact and demontrates that not all Y and mt DNA are of recent African origin.

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                • #9
                  No. The point is that all mtDNA that has ever been tested indicates a common matrilineal ancestor 150,000 to 200,000 years ago -thus NONE of the tested matrilines can be considered to be derived from H. neanderthalensis or H. erectus. Same goes for y-DNA, except the common ancestor of all y-lines lived a lot later (perhaps 80,000 to 100,000 years ago).

                  The genelines of mtDNA & y-DNA travel independent of one another. It would seem odd that genetic drift would, in both cases, favor African lineages in both cases. It could happen, but Out of Africa proponents have long argued that this supports their theory.

                  John Relethford supports a "mainly Out of Africa" theory, in which the overwhelming majority of our gene lines are derived from Africa, with a few being derived from Eurasian archaics. This would explain why, at random, both the t-line & mt-line would be African. It strikes me as odd that the really important characteristics of humankind would be thoroughly sapienized in all mixed populations, while the really superficial stuff like skin color, nose shape, etc. would retain archaic characteristics.

                  Timothy Peterman

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                  • #10
                    Originally posted by T E Peterman
                    No. The point is that all mtDNA that has ever been tested indicates a common matrilineal ancestor 150,000 to 200,000 years ago -thus NONE of the tested matrilines can be considered to be derived from H. neanderthalensis or H. erectus. Same goes for y-DNA, except the common ancestor of all y-lines lived a lot later (perhaps 80,000 to 100,000 years ago).

                    The genelines of mtDNA & y-DNA travel independent of one another. It would seem odd that genetic drift would, in both cases, favor African lineages in both cases. It could happen, but Out of Africa proponents have long argued that this supports their theory.

                    John Relethford supports a "mainly Out of Africa" theory, in which the overwhelming majority of our gene lines are derived from Africa, with a few being derived from Eurasian archaics. This would explain why, at random, both the t-line & mt-line would be African. It strikes me as odd that the really important characteristics of humankind would be thoroughly sapienized in all mixed populations, while the really superficial stuff like skin color, nose shape, etc. would retain archaic characteristics.

                    Timothy Peterman

                    Please read Templeton's latest paper for a clearer understanding of what is now being proposed.

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                    • #11
                      My understanding is that the 700,000 BP & 1.9 million BP migrations were detected using nuclear DNA. I see nothing in the article that proposes this level of variation in either mtDNA or y-DNA. I don't even see any mention of mtDNA or y-DNA -at least following the link offered above.

                      There are other cases were alleles can have different forms (eg, blood types) & can exist within a population for a long time. If two alleles appeared 700,000 years ago, they could have both been present in mt-Eve's population.

                      I have yet to see anyone on this forum write about the inversion of Chromosome 17. Inverted & non-inverted forms do NOT recombine. The inversion has been dated to 2 to 3 million years ago AND the inversion is only found among a minority of northern Europeans...

                      Timothy Peterman

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                      • #12
                        Complete Study

                        I can try and get the complete study to you if you would like.

                        Comment


                        • #13
                          Derinos

                          I am trying to summarise a narrative of my own understanding of the excellent posts on this subject; my conclusions may need trimming, of course! To ruminate,

                          Did Homo Sapiens Sapiens (HSS) come Out of Africa?
                          Yes.

                          How many times?
                          More than once.

                          Were we all of exactly the same tribe or family?
                          No. The Hg and subclades distribution suggests multiple tribes came out in an unclear (as yet) sequence, going off first East, then North, then west. all over many decamillennia. But all were HSS, differentiated from earlier species like Neanderthalensis, Heidelbergensis, Erectus variants, and the wide variety of "archaics" indicated by the fossil record.

                          Did any "archaics" move out of Africa?
                          Many times, over probably more than 2 million years and a few may well have been out of there awaiting us.

                          Is there detectable genetic relationship of HSS to "archaics" in examining today's DNA samples?
                          Not so far by MtDNA and YDNA sequences. Even Neanderthalensis, also classified as Homo Sapiens, has so far failed to show any MtDNA continuity.
                          But some nuclear features in moderns (like the Chr.17 reversal associated with longevity in Icelanders) are very archaic, although they could have been acquired at any time in the evolutionary period and carried until now due to isolation preventing loss by genetic drift.

                          How many geographic routes could Hominids take to leave Africa?
                          Dryland routes at today-minus-250Meter sea levels during the height of glaciations could have numbered three; two in the Middle East and one at Gibraltar.

                          Migrant water travel requires intelligence . HSS certainly did use it to reach Australia ca 50,000 YBP and who knows where else.. Neanderthalensis could certainly have done some rafting. An archaic hominid like Heidelbergensis ( of say, 500,000 YBP) who makes hand axes of the Boxgrove type, could have used felled logs, even log rafts, to get across water. Motivation and reasoning to do so, and how far, is an unknown factor with no archaeological confirmation; but one must be impressed by the surprisingly adequate housebuilding of recent Japanese archaic works in that timescale of over half a million years.

                          Could there have been, evolution of hominids elsewhere than in Africa ?
                          Why not, given enough time and the right climate? Java man is still a possibility.

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                          • #14
                            Derinos,

                            Thank you for providing the details. We are in agreement on this issue. I just want to make sure that people don't think this "archaics out of Africa many times" debunks the mtDNA & y-DNA analysis of recent African origins.

                            Timothy Peterman

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                            • #15
                              as far as my understanding goes...

                              our dna shows it's earliest variation in Africa.

                              aaaaaaaaaaaaaaaaaaa

                              Did monkeys come out of Africa? maybe a study is needed on the out of Africa Monkey?

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