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Natural Science Forum / Biology / Paleontology / April 2004The Levant versus the Horn of Africa: Evidence for Bidirectional Corridors of Human Migrations
http://home.ripway.com/2004-1/62802/levant.pdf The Levant versus the Horn of Africa: Evidence for Bidirectional Corridors of Human Migrations J. R. Luis, D. J. Rowold, M. Regueiro, B. Caeiro, C. Cinnioglu, C. Roseman, P. A. Underhill, L. L. Cavalli-Sforza, and R. J. Herrera1 Paleoanthropological evidence indicates that both the Levantine corridor and the Horn of Africa served, repeatedly, as migratory corridors between Africa and Eurasia. We have begun investigating the roles of these passageways in bidirectional migrations of anatomically modern humans, by analyzing 45 informative biallelic markers as well as 10 microsatellite loci on the nonrecombining region of the Y chromosome (NRY) in 121 and 147 extant males from Oman and northern Egypt, respectively. The present study uncovers three important points concerning these demic movements: (1) The E3b1-M78 and E3b3-M123 lineages, as well as the R1*-M173 lineages, mark gene flow between Egypt and the Levant during the Upper Paleolithic and Mesolithic. (2) In contrast, the Horn of Africa appears to be of minor importance in the human migratory movements between Africa and Eurasia represented by these chromosomes, an observation based on the frequency distributions of E3b*-M35 (no known downstream mutations) and M173. (3) The areal diffusion patterns of G-M201, J-12f2, the derivative M173 haplogroups, and M2 suggest more recent genetic associations between the Middle East and Africa, involving the Levantine corridor and/or Arab slave routes. Affinities to African groups were also evaluated by determining the NRY haplogroup composition in 434 samples from seven sub-Saharan African populations. Oman and Egypt's NRY frequency distributions appear to be much more similar to those of the Middle East than to any sub-Saharan African population, suggesting a much larger Eurasian genetic component. Finally, the overall phylogeographic profile reveals several clinal patterns and genetic partitions that may indicate source, direction, and relative timing of different waves of dispersals and expansions involving these nine populations. >http://home.ripway.com/2004-1/62802/levant.pdf > [quoted text clipped - 9 lines] >corridor and the Horn of Africa served, repeatedly, as migratory >corridors between Africa and Eurasia. ... Thanks for posting this. I am still unable to correlate the world Y chromosome phylogenetic chart with the mtDNA as the Y chromosome tree appears to have an early step , M89, for which there is no known equivalent in the mtDNA. Quoting from the article: "Both the Horn of Africa and the Levantine corridor have been proposed as main passageways for migrations of anatomically modern humans out of Africa (Cavalli- Sforza et al. 1994; Lahr and Foley 1994). The distributions of [Y chromosome] haplogroups C and D suggest early dispersals (50-45 thousand years [ky] ago) of ancestors of these lineages from the Horn of Africa to southern Asia (Underhill et al. 2001b), most likely in conjunction with mtDNA haplogroup M (Quintana-Murci et al. 1999; Kivisild et al. 1999)." While the presence of 'M' mtDNA haplogroups in Africa may be due to back-migration as previously illustrated in Forster's slide 11, I have previously thought that RPS4Y ("haplogroup C") correlated with mtDNA M. So, so far so good. " Posterior demic movements, such as the one represented by the dissemination of the ancestral M89 chromosomes and the 10873T mtDNA lineage to Eurasia, most likely occurred via the Levantine corridor, ~45 ky ago (Underhill et al. 2001b; Quintana-Murci et al. 1999). Here, it is suggested that the M89 Y chromosomes correlate with mtDNA macro-haplogroup N and this is where I run into difficulty as I don't know of any European or Eurasian mtDNA haplogroups which should be closer to those of Africans than any found in Australia or the New World. Gisele > >http://home.ripway.com/2004-1/62802/levant.pdf > > [quoted text clipped - 39 lines] > closer to those of Africans than any found in Australia or the New > World. ...you put your Y-chromosome in, take a X-chromosome out and shake it all about - that's what a male is all about.... Why are you (or anyone) trying to correlate Y-chromosomes with mtDNA? Surely the Y-chromosomes will be able to chance without a corresponding change in mtDNA (and vice versa) - which ultimately leads to a conclusion "no correlation"? That any apparent "correlation" is just a chance happenstance.  SignatureSIR - Philosopher unauthorised ----------------------------------------------------------------- The one who is educated from the wrong books is not educated, he is misled. ----------------------------------------------------------------- [...] >Why are you (or anyone) trying to correlate Y-chromosomes with mtDNA? To increase the usefulness of both types of data. >Surely the Y-chromosomes will be able to change without a >corresponding change in mtDNA (and vice versa) - which ultimately >leads to a conclusion "no correlation"? That any apparent >"correlation" is just a chance happenstance. More than half of all non-Africans have the 10873T mtDNA mutation mentioned below. The Y chromosome sites are probably even slower-evolving. "Posterior demic movements, such as the one represented by the dissemination of the ancestral M89 chromosomes and the 10873T mtDNA lineage to Eurasia, most likely occurred via the Levantine corridor, ~45 ky ago (Underhill et al. 2001b; Quintana-Murci et al. 1999)." (Luis, 2004) "The third large sub-cluster of M168 lineages is characterized by the M89/M213 mutations at the root of Groups VI-X. As discussed above, this sub-cluster is suggested to have evolved in East Africa, from where it dispersed to Eurasia through the Levantine corridor around 45000 years ago. This dispersal would have also involved several mtDNA haplogroups characterized by the 10873 C -->T mutation (Quintana-Murci et al. 1999)." (Underhill, 2001) ...but the M89/213 haplotypes have a restricted distribution as they appear to be mainly found around the Middle East, Europe & Central Asia whereas mtDNA sequences which had 10873T & related variants were carried as far as the Americas and Australia. In these locations, the M89/213 haplotypes have an additional mutation in common - M9 and, therefore, I am inclined to associate this mutation with these mtDNA haplogroups rather than its precursor. That could mean that the mtDNA sequences which were carried alongside the M89/213 Y haplotypes to Europe and surrounding area no longer exist or, I suppose, it could mean nothing. Gisele > [...] > >Why are you (or anyone) trying to correlate Y-chromosomes with mtDNA? > > To increase the usefulness of both types of data. Snip > ...but the M89/213 haplotypes have a restricted distribution as they > appear to be mainly found around the Middle East, Europe & Central [quoted text clipped - 8 lines] > > Gisele Actually, Gisele, I think that perhaps the value of parallel Y-chromosome and mtDNA analysis goes quite a bit beyond the more esoteric details that you point out. The dynamics of the two processes would seem to be very similar, i.e. mtDNA runs almost exclusively down the matrilineal lines and the "Y's" run down the patrilineal lines. Both are obviously DNA strands, logically affected by many of the same processes, mutational forces, etc. While there are some cases where one or the other might be "wiggled" by outside influences, for example an ancient invading army is perhaps more likely to spread "Y's" than mtDNA. Victorious returning armies of the past are probably more likely to bring back mtDNA in the form of women and girls taken into slavery than "Y's". Still, Y and mtDNA should bring us more or less the same "messages" when it comes to major population migrations, LCAs, etc. Any time I have two independent but "related" processes that give the same answers, I have a reasonable confidence in the results. Think of the fact that major volcanic eruptions can be dated with tree rings, atomic dating, stratiography, and even in recent times legends and historical records. When all of those start to agree, you can have confidence not just in the actual date, but also in the processes used. On the flip side, if there are major, otherwise unexplicable differences between the mtDNA and Y-chromosome answers, it might just be an indication of the "variability" of the results. In ancient times, Id suggest that there were very few "armies of occupation" and more nomadic incursions. Armies of occupation could lead to serious asymetries between Y and mtDNA results, nomadic incursions would bring along the whole family! 8-) Regards bk > [...] > >Why are you (or anyone) trying to correlate Y-chromosomes with mtDNA? > > To increase the usefulness of both types of data. Well I suppose that is a good answer to a rhetorical question... a rhetorical answer? :-) > >Surely the Y-chromosomes will be able to change without a > >corresponding change in mtDNA (and vice versa) - which ultimately [quoted text clipped - 11 lines] > ky ago (Underhill et al. 2001b; Quintana-Murci et al. > 1999)." (Luis, 2004) I still don't like that time frame they give. > "The third large sub-cluster of M168 lineages > is characterized by the M89/M213 mutations [quoted text clipped - 17 lines] > Europe and surrounding area no longer exist or, I suppose, it could > mean nothing. But "correlation" is a statistical function that leads to universal conclusions on a probability factor. However, the Y-chromosome and mtDNA live separate lives and the twain never meet, even though they get rather close to each other! In order to "correlate" Y-chromosomnes to mtDNA, you would have to argue a function of one acting on the other as in a fatal attraction. AFAIK no such function exists. Also it would mean it would always occur. You say it doesn't. Therefor another reason must exist. IIRC the Y-chromosome Adam is only some 80K years old, when the mtDNA Eve is some 120 -> 170K years old (depending on claimant). One thing is certain, there can not have been "immaculate conceptions" for some 40 -> 90 K years. Think of all the bibles one would have to generate... It would be fair to say that there must have been a few milk men, gas meter readers etc to serve the function of the missing Adam in that time. They too must have met an untimely end -probably as a result of Adam coming home unexpectedly. I don't see a problem with an extinction of a lineage. It has happened before as the DNA Adam and Eve's show us and I'm sure there are more of them. SignatureSIR - Philosopher unauthorised ----------------------------------------------------------------- The one who is educated from the wrong books is not educated, he is misled. ----------------------------------------------------------------- Snippage. . . . . > But "correlation" is a statistical function that leads to universal > conclusions on a probability factor. However, the Y-chromosome and [quoted text clipped - 4 lines] > would mean it would always occur. You say it doesn't. Therefor another > reason must exist. Afraid that you may have missed a point. I dont think that either I or the good Ms. Horvat were suggesting that the Y-chromosome and mtDNA were intertwined in some intracellular manner, mearly in the external "physical world" sense. Except in very special cases, where mtDNA goes, so goes the Y-chromosome. If you were to trace a map of human migrations, using the respective genetic lines, they should for the most part overlay, i.e. the "same" answer from two different and distinct sources. Dont know if it was accidental or intentional, but recommend a review of what was being discussed. Regards bk > Snippage. . . . . > [quoted text clipped - 12 lines] > "physical world" sense. Except in very special cases, where mtDNA > goes, so goes the Y-chromosome. The fact that Y-chromosome and mtDNA exists in the same cell (but different parts), wasn't really the issue at all. What I suggested was that a mathematically predictable correlation between a particular mtDNA and Y-chromosome doesn't seem to be logical - IF that was being suggested. That such would result in, is an argument to say, "Because mtDNA XXXX is found here, Y-chromosome YYYY will be found in the male population, the probability factor that this will be so is 95.4%." For that statistical argument to apply, a "fatal attraction" would have to exist between females of a particular mtDNA, and males of a particular Y-chromosome. That each had an attribute of unique desire to the other, to the exclusion of others (perhaps a hairy arse would do the trick?) I note your argument against the molecular clock, and I agree to a large degree with you. Likewise, in this case, I would not accept a statistical predictor for the existence of any particular DNA in a gender because of the existence of another in the opposite gender. On the other hand, I also don't say that a co-existence does NOT occur, I also say that it NEED NOT occur. Further more I do not say that the occurrence Gisele has identified does not exist - only that a "correlation" (a statistical function) cannot be claimed, even if such may appear to exist. > If you were to trace a map of human > migrations, using the respective genetic lines, they should for the most > part overlay, i.e. the "same" answer from two different and distinct > sources. I take Gisele's word for the existence as she stated it. This comes from observations and a lot of tedious painstaking work sampling and testing, not a formula, a statistical probability calculation. > Dont know if it was accidental or intentional, but recommend a review of > what was being discussed. Ahh.... no, I think the word graphics may have been a bit fuzzy around the edges, causing loss of focus? SignatureSIR - Philosopher unauthorised ----------------------------------------------------------------- The one who is educated from the wrong books is not educated, he is misled. ----------------------------------------------------------------- > > Snippage. . . . . > > [quoted text clipped - 20 lines] > mtDNA XXXX is found here, Y-chromosome YYYY will be found in the male > population, the probability factor that this will be so is 95.4%." Ah, now I understand what you are saying! I think anyway. You are of course correct that a "change" in the mtDNA has absolutely nothing to do with a "change" in the Y-chromosome. In fact that independence is what I would be counting on in my little idea. Just hypothetically now, lets assume that a given train of mtDNA changes leads one to believe that there was a trail of "Caucasian" mtDNA moving east to west across central Asia. For example lets just hypothesize that this was the Scythian migration westward. This would be defined by a series of "commonalities" where for example Finns turned up with mtDNA that could logically have only originated in the area of central Asia. If tracking the Y-chromosome "commonalities" (which are totally and completely different from the mtDNA indicators), shows the same line of advance, then and only then does the conclusion that the Finns ancestors migrated from central Asia make sense. If the Y-chromosome commonalities only led to the Australian aborigines, well. . . . . you have NOTHING either way just two strange "just so" findings. > For that statistical argument to apply, a "fatal attraction" would > have to exist between females of a particular mtDNA, and males of a > particular Y-chromosome. That each had an attribute of unique desire > to the other, to the exclusion of others (perhaps a hairy arse would > do the trick?) Which is just about what happens in human society I believe. HG males take mates from within the "tribe" or at least from within neighboring tribes or vice versa depending on the social mores and practices. > I note your argument against the molecular clock, and I agree to a > large degree with you. Likewise, in this case, I would not accept a > statistical predictor for the existence of any particular DNA in a > gender because of the existence of another in the opposite gender. OK, you lost me here. Hopefully its explainable by a mutual misunderstanding. 8-) > On the other hand, I also don't say that a co-existence does NOT > occur, I also say that it NEED NOT occur. Further more I do not say > that the occurrence Gisele has identified does not exist - only that a > "correlation" (a statistical function) cannot be claimed, even if such > may appear to exist. Drawing a line of inference through one point of even very good data is a very risky thing to do I think. It would take more than a little bit of diligent study to verify or deny that the "migration map" as traced with mtDNA either agrees or disagrees with the similar map traced with y-chromosome. If by some circumstance they more or less match, then I would suggest that we have proven a very powerful tool to map out ancient migrations. If they disgree in a fundamental sense, I would suggest that we would have debunked a particularly insidious little piece of pseudo-science. > > If you were to trace a map of human > > migrations, using the respective genetic lines, they should for the most [quoted text clipped - 4 lines] > from observations and a lot of tedious painstaking work sampling and > testing, not a formula, a statistical probability calculation. I also trust Gisele's work. While I certainly do not understand all of the details of her findings, Ive got a certain confidence that if she says she found something it is there. I may quibble a bit with the conclusions, but certainly not from the standpoint of worrying about her findings. > > Dont know if it was accidental or intentional, but recommend a review of > > what was being discussed. > > Ahh.... no, I think the word graphics may have been a bit fuzzy around > the edges, causing loss of focus? Fuzzy is a problem. Regards bk [..] > > The fact that Y-chromosome and mtDNA exists in the same cell (but > > different parts), wasn't really the issue at all. What I suggested was [quoted text clipped - 16 lines] > of "commonalities" where for example Finns turned up with mtDNA that > could logically have only originated in the area of central Asia. Well you are much closer than you think - if "Central Asia" was in fact central Asia and not West Asia (which doesn't exist). I have placed them (and the Saami neighbours) originating from around the head waters of the Irtysh to the Yenisey river on the steppes north of the Altai mountains at around 9000 BCE, according to investigation I did a while ago. > If tracking the Y-chromosome "commonalities" (which are totally and > completely different from the mtDNA indicators), shows the same line > of advance, then and only then does the conclusion that the Finns ancestors > migrated from central Asia make sense. If the Y-chromosome commonalities > only led to the Australian aborigines, well. . . . . you have NOTHING either > way just two strange "just so" findings. I don't see it as simple as that. First of all a people movement over a very long time doesn't occur by people marching in a long line, rest and get up and move again. I would suggest a leapfrogging of people to find new spaces to live in as population that also grows. New families/tribes want fresh hunting grounds and move beyond the existing people and settle, get old and comfortable where they are. Another younger generation leapfrogs them and so on. In each move there is a certain "drag" of people mixing, disagreeing and getting their nose out of joint and go off in a different direction. There is a certain amount of absorption of new people into a group that way. The Y-chromosome is rather prone to drift anyway. So you can start with a predominant Y-chromosome of a particular type and gradually change to being predominant of a completely different type that was not within the group to start with. So, if one can track this change, match the movement to a genetic distance (if possible) that fits reasonably with a probable chronology you should have a reasonable certain movement path despite a complete change. For further proof of the theory, archaeological find of cultural items can help to support the theory - as will language. > > For that statistical argument to apply, a "fatal attraction" would > > have to exist between females of a particular mtDNA, and males of a [quoted text clipped - 5 lines] > take mates from within the "tribe" or at least from within neighboring > tribes or vice versa depending on the social mores and practices. True that is so by necessity - only human nature is such that there is a leakage from tribes for various reasons, not limited to selecting partners. But the proposal I put forward was that someone, as a passer by from another tribe would not be attracted to to the tribe they are passing, and vice versa. Eg. Neanderthal and Homo Sapien - they co-existed to about the end of the ice age but did not interbreed. I don 't see a similar situation within Homo Sapien Sapien - whilst it probably appears to exist, it is one of opportunity (or lack thereof) that causes that appearance. I have read that in the future, due to our modern mobility and the high population movements currently, all people will eventually be a nice "coffee" (with milk) colour. That the opportunities are now greatly extended and geographical remoteness, sea or contours are no longer formidable barriers. [not important] > > On the other hand, I also don't say that a co-existence does NOT > > occur, I also say that it NEED NOT occur. Further more I do not say [quoted text clipped - 11 lines] > suggest that we would have debunked a particularly insidious little piece > of pseudo-science. I have not seen one overlaid on another. I don't know it the Y-chromosome data is available yet to make a good map. > > > If you were to trace a map of human > > > migrations, using the respective genetic lines, they should for the most [quoted text clipped - 12 lines] > from the > standpoint of worrying about her findings. Ahh... yes, this field moves ahead far too fast for me to keep up to date. I'm afraid I'm being left behind - at least till I find a need/will/time to do a burst of serious reading.... Do as I do when you don't understand, just nod and say "mmmmm" and look bright eyed, it gives an impression of having understood. Saying only "mmmmm" ensures the mouth stays shut, so as not to betray you :-) > > > Dont know if it was accidental or intentional, but recommend a review of > > > what was being discussed. [quoted text clipped - 3 lines] > > Fuzzy is a problem. ...but not to computer nerds, who find it extremely useful in "fuzzy logic"! SignatureSIR - Philosopher unauthorised ----------------------------------------------------------------- The one who is educated from the wrong books is not educated, he is misled. ----------------------------------------------------------------- > > > Snippage. . . . . > > > [quoted text clipped - 106 lines] > Regards > bk By the time of farming there is some evidence that a cutlure based on a warrior religion, using horse drawn chariots, and a language expanded out of the middle east. What seems to have happened is the young bucks took over from the neighbors who lacked horse drawn chariots and may not have had a warrior relgion. The women and kids stayed home with papa. The Y chromsome moved and the culture, religion, and language while undergoing transformation moved. Women also seemed to have moved around a lot some way. I'm guessing they may have gotten stolen or traded based on a mildly novel appearance or maybe natural selection was at work on the entire unit. Snippage. . . . . .. > > Fuzzy is a problem. > > [quoted text clipped - 12 lines] > have gotten stolen or traded based on a mildly novel appearance or maybe > natural selection was at work on the entire unit. The "problem" is that there are a BUNCH of different indicators that might mark ancient human migrations. Some are pretty much hard and fast. For example, find a bunch of skeletons in Poland, all mixed up with the emblems of Napoleon's Grand Armee, and that would be a pretty good sign that there were lots of Frenchmen in Poland in the early 1800s. Matches well with written history and oral histories, etc. Probably a meaningful correlation. Now, if you found that same mass burial of Old Guard troopers, but got a C-14 dating of 5000BC from each and every scrap of organic material, would you question the oral and written records and the metalurgical prowness and powers of prognostication of those ancient Poles (making all of those brass buttons and forcasting the rise of "l' Emperor" by 6000 years? OR would you perhaps question the validity of your C-14 methodology? 8-) Some would simply have all "rock solid" archaeological evidence and cultural records dumped on the floor in favor of their "pet" , but essentially unprovable analysis techniques! But to each his own. . . . just not sure that science is allowed to "pick and choose" from the available data sources. Regards bk The Y-chromosome and MtDNA contraction. "Bob Keeter" <rkeeter@earthlink.net> wrote If you were to trace a map of human > migrations, using the respective genetic lines, they should for the most > part overlay ... but, I guess, they don't. Maybe there is a problem with the model. What about if the migratory direction was reversed and a homo sapient Adam met a non-quite homo sapient Eve like Wolpoff seems to suggest? Regards. Robert > The Y-chromosome and MtDNA contraction. > [quoted text clipped - 9 lines] > > Robert Now THERE is where it gets interesting! Lets just suppose that the two mappings DO disagree! Just about all of the theories of human evolution hinge around "humans" originating in one or more locations and then diffusing out across the world. It actually makes no real difference if its one nucleus (in Africa, Asia or whereever), or several (in African AND Asia for example), the concept is that the "deltas" in either the mtDNA or Y-chromosome would radiate out from these points of origin. Considered seperately, you could probaly produce some sort of "nearest neighbors" map of this little diasphora using either as a reference. The trick with parallel but independent data sources is that you increase the crediblilty (statistically) by a huge degree if those two sources agree (call it "processing gain" for lack of a better term). I have no doubt that most of the research in this area is done by credible scientists trying to work with the data they have and extract the most information possible. That goal in itself, as worthy as it is, just might be the "problem with the model"! Not just in Paleoanthropology but in other scientific and technical disciplines, this drive sometimes pushes researchers to see "under the noise", extracting "conclusions" when the signal-to-noise ratio (SNR) just does not support it! Let me give you an example from the world of signal processing. Lets take a transmitted radio signal where the SNR is less than that required to extract the encoded information (<3-6db depending!). No matter what you do to that signal (assuming no preconceived notions on the content and that the offending noise is white noise), you can not extract the intelligence! You may extract SOMETHING from that hissing and poping that you hear, but it is highly unlikely to be the information encoded. Now, lets say you presume that there is another "channel", on a different frequency, transmitting the same exact intelligence but again at a SNR far too low to extract the intelligence. (in this case, lets imagine that the first signal is mtDNA and the second signal, the Y-chromosome, just to reiterate the "Tie in"! 8-) ) Lets again think in the RF domain with bad SNR. If I have one tuner set to the first signal and a second receiver tuned to the second I will get two outputs, neither of which is intelligible by itself. With some pretty slick signal processing though, I can add the two signals. However, a very interesting and useful characteristic of "white noise" is that it is truely statistically random. In other words if I mathematically add two white noise streams I will tend to get a noise reduction function. The encoded information on the other hand is decidedly non-random adding that portion of the two signalsl tends to increase the modulated component of the signal's power by 3db! So, noise starts cancelling itself and the signal starts increasing in raw power. Now, if I add in enough separate and independent channels, suddenly the SNR is not quite so disadvantageous! 8-) (If you are interested in a more detailed and technically rigorous discussion, google up some of the theory behind "spread spectrum".) In this example, mtDNA and y-chromosome both have the potential to carry the "bread crumbs" that might be useful for tracing uncharted human migrations. With either, standing alone, I have to wonder mightily about the SNR. Others probably worry more about the viability of their pet theories (and maybe even theses) extracted from the hissing and popping of that one single, noisy mtDNA channel. 8-) Regards bk "Bob Keeter" <rkeeter@earthlink.net> wrote in message news:<lqn0c.26501$ >Just about all of the theories of human evolution hinge around "humans" originating in one or more locations and then diffusing out across the world. In other words, the current approach limits its horizon to the Homo Sapiens Sapiens gene pool. >The concept is that the "deltas" in either the MtDNA or Y-chromosome would radiate out from these points of origin. But what about if the current gene pool were to contain pre-Homo Sapiens Sapiens strains (strains of populations that were not the first to reach the Homo Sapiens Sapiens threshold)? In that case, obviously, the "deltas" would not match. >>Not just in Paleoanthropology but in other scientific and technical disciplines, this drive sometimes pushes researchers to see "under the noise", extracting "conclusions" when the signal-to-noise ratio (SNR) just does not support it! "Drives" and, in anthropology, I would add, big ideological agendas. Regards Robert Call > "Bob Keeter" <rkeeter@earthlink.net> wrote in message news:<lqn0c.26501$ > [quoted text clipped - 4 lines] > In other words, the current approach limits its horizon to the Homo > Sapiens Sapiens gene pool. Not really, but that was a convenient example. Im thinking that in a "macro" sense it might apply outside of a single species, but this is a paleoanthropology newsgroup so Im leaving out dogs, horses and giraffes! ;-) Seriously, most of the "diffusion" diagrams Ive seen have been focused on the last 100k or so of human history. > >The concept is that the "deltas" in either the MtDNA or Y-chromosome > would radiate out from these points of origin. [quoted text clipped - 3 lines] > first to reach the Homo Sapiens Sapiens threshold)? In that case, > obviously, the "deltas" would not match. Perhaps. I think that you could always find examples of "incongruities". What I was getting at was more along the lines of LCA on the mtDNA turns up at X mya whereas the same logic applied to a strand of Y-chromosome shows an LCA at X+50% mya. Thinking macroscopic certainly not microscopic. Anyway, Ive got a funny feeling that the finest resolution in the molecular clock for any species might be in the hundreds of generations or so, so there would need to be a REALLY big delta before that delta itself could be considered significant. > >>Not just in Paleoanthropology but in other scientific and technical > disciplines, this drive sometimes pushes researchers to see "under the [quoted text clipped - 6 lines] > > Robert Call Ideological agendas, egos, and soft statistics go a long way with SOME people. 8-) Regards bk "Bob Keeter" > > Anyway, Ive got a funny feeling that the > finest resolution in the molecular clock for any species might be in the > hundreds of generations or so, so there would need to be a REALLY > big delta before that delta itself could be considered significant. "hundreds of generations": 5000/6000 years? Is that for each mutation to occur? That would be consistent with the fossil record.There has been very little change in the physical appearance of the European population, for example. in the last five thousand years. Also there were no migrations in historical time in the South-North direction. (Let us not forget that the Romans wrote in their maps, in correspondence of the Sahara, "hic sunt leonem" - no human activity here) But there were plenty of North-South and East-West migrations. Regards. r.c. > > >>Not just in Paleoanthropology but in other scientific and technical > > disciplines, this drive sometimes pushes researchers to see "under the [quoted text clipped - 12 lines] > Regards > bk > "Bob Keeter" <rkeeter@earthlink.net> wrote in message news:<lqn0c.26501$ > [quoted text clipped - 4 lines] > In other words, the current approach limits its horizon to the Homo > Sapiens Sapiens gene pool. Just a small quibble - both the mtDNA EVE and Y-chromosome Adam, predates Homo Sapien Sapien by a long way. To about Homo Sapien Archaic (early Cro-Magnon). [..] SignatureSIR - Philosopher unauthorised ----------------------------------------------------------------- The one who is educated from the wrong books is not educated, he is misled. ----------------------------------------------------------------- > > "Bob Keeter" <rkeeter@earthlink.net> wrote in message news:<lqn0c.26501$ > > [quoted text clipped - 8 lines] > predates Homo Sapien Sapien by a long way. To about Homo Sapien > Archaic (early Cro-Magnon). The statement's intent was to set up terms of reference so apples with apples could be compared. In regard to the time frame of HSS, it is often reported that modern humans first arose in Africa about 100,000/120,000 years ago. I assume that for "modern humans" is intended HSS. Adam has been located, in the high end, at 270,000 ya and, in the low end, at 51,000 ya; Eve at 240,000 ya and 40,000 ya respectively. The low ends of both, Adam and Eve, fall within the modern humans period. The high ends of both fall within the fuzzy period of the last Homo Erectus. This huge, immense gap of time opens up the possibility of gene crisscrossing between different types of HS, archaic HS, and late HE. In these cases, the two Deltas would not match, and that was the point I was trying to make. Regards. r.c. > > > "Bob Keeter" <rkeeter@earthlink.net> wrote in message news:<lqn0c.26501$ > > > [quoted text clipped - 15 lines] > humans first arose in Africa about 100,000/120,000 years ago. I assume > that for "modern humans" is intended HSS. No that is where the misconception lies. HSS is considered to come into existence at about 40 -> 35 ky ago. There is talk about this having been a "second wave" from Africa. Whatever it is, it refers to a time when the "technological" evolution really started to gather momentum. For millions of years the height of Homo evolution was restricted to fire, sticks and stones very crudely worked. Neanderthals and Homo Sapien Archaic existed together. Recent theory is that neither could handle the climatic change, but the newcomers could. The Neanderthals became extinct, Homo Sapien survived, possibly due to a new influx of people. > Adam has been located, in > the high end, at 270,000 ya and, in the low end, at 51,000 ya; Eve at > 240,000 ya and 40,000 ya respectively. You suggest much wider times than I have seen. Oldest Eve is around 170 K, oldest Adam is 80 K, as near as I have seen - nor have I seen such a huge variance to the youngest either. > The low ends of both, Adam and > Eve, fall within the modern humans period. The high ends of both fall > within the fuzzy period of the last Homo Erectus. This huge, immense > gap of time opens up the possibility of gene crisscrossing between > different types of HS, archaic HS, and late HE. No, there is no evidence of it. IF it did occur, Neanderthals is the logical "proof" - none exists and it has been tested. There is no cross-over. Further more Homo Erectus lived from approximately 2 million to around 400,000 years ago. Well outside the scope. > In these cases, the > two Deltas would not match, and that was the point I was trying to > make. SignatureSIR - Philosopher unauthorised ----------------------------------------------------------------- The one who is educated from the wrong books is not educated, he is misled. ----------------------------------------------------------------- >>No that is where the misconception lies. HSS is considered to come into existence at about 40 -> 35 KY ago. So then, since HSS is the scientific name for modern humans, the statement "modern humans first arose in Africa about 100,000/120,000 years ago", which appears so often in the public & scientific press, is incorrect and creates misconceptions. >There is talk about this having been a "second wave" from Africa. I guess the Out of Africa doctrine has to increase the number of its dogmas to square its theology. >>Recent theory is that neither could handle the climatic change, but the newcomers could. So somebody coming from the Tropics could handle the ice age? Interesting! They must have found some substitute for vitamin D or had an on-the-spot mutation. >You suggest much wider times than I have seen. Oldest Eve is around 170 K, oldest Adam is 80 K, as near as I have seen Actually, my book says that, in the original Wilson study, the upper limit for Eva was set at 290 KY. In the 1991 study was set at 249 KY, and, in the 90s, somebody called Templeton came up with an upper limit of 1 million years. In the first Y study, Adam was a pygmy living 200 KY. The ZFY study found an optimal date for Adam of 270 KY, and so on. >>This huge, immense gap of time opens up the possibility of gene crisscrossing between different types of HS, archaic HS, and late HE. >No, there is no evidence of it
I don't think such a statement can be made yet since the recovery, analysis and comparison of hominids' DNA is just started and has a long way to go. But let us see the implications of your statement. Stating that there was no genic exchange, and that Homo erectus, all over the world, had evolved into something else, you are implying that there were unrelated evolutionary centers independently heading toward the "sapiens" condition. This was also the core of the polygenist theory. Regards. r.c. > >>No that is where the misconception lies. HSS is considered to come > into existence at about 40 -> 35 KY ago. [quoted text clipped - 3 lines] > years ago", which appears so often in the public & scientific press, > is incorrect and creates misconceptions. Yeah well, I wish there were less goal posts using same or similar terms - however that isn't the case. The "modern humans" and "anatomically modern humans" differ. One is Homo Sapien and the other is Homo Sapien Sapien, except from when they refer to the same - Homo Sapien (without the second "sapien") as being like we are. Not my idea.... > >There is talk about this having been a "second wave" from Africa. > > I guess the Out of Africa doctrine has to increase the number of its > dogmas to square its theology. Eh? You know "theology" is about religion, science is NOT religion. Please don't confuse the two unrelated issues. > >>Recent theory is that neither could handle the climatic change, but > the newcomers could. > > So somebody coming from the Tropics could handle the ice age? > Interesting! They must have found some substitute for vitamin D or had > an on-the-spot mutation. You are no longer being serious, and only sarcastic. NO person "from the tropics" back then ever saw any ice! That is plain ridiculous. > >You suggest much wider times than I have seen. Oldest Eve is around > 170 K, oldest Adam is 80 K, as near as I have seen [quoted text clipped - 6 lines] > In the first Y study, Adam was a pygmy living 200 KY. The ZFY study > found an optimal date for Adam of 270 KY, and so on. Well.... you will mix in theology into the real world.... You can't claim anyone was a "pygmy" - because that is arguing it is known WHO was the first Adam. It simply isn't known nor is it important in any way to know either. Reality is, as with the mtDNA Eve, there isn't ONE but many "Adams". It is a theoretical "first" only based in certain common DNA. > >>This huge, immense gap of time opens up the possibility of gene > crisscrossing between different types of HS, archaic HS, and late HE. [quoted text clipped - 4 lines] > analysis and comparison of hominids' DNA is just started and has a > long way to go. Not only can it be made, it HAS been made. Of course, you CAN argue a relatedness based in certain "common genes", but then you CAN argue relatedness with a bloody cauliflower as humans share 17% of genes with a caulie - and those people who argue such "relatedness" use the 17% for their BRAINS. > But let us see the implications of your statement. Stating that there > was no genic exchange, and that Homo erectus, all over the world, had > evolved into something else, I have said nothing of the kind at all. Homo Erectus went extinct like the Neanderthal did. > you are implying that there were > unrelated evolutionary centers independently heading toward the > "sapiens" condition. This was also the core of the polygenist theory. What ARE you talking about? Look even according to you there is an "Adam and Eve" the theoretical first Mum and Dad of the humans. How the hell can you then argue "poly-" anything for origin? It is the same as you arguing being able to be physically in two different places simultaneously - it can't happen. SignatureSIR - Philosopher unauthorised ----------------------------------------------------------------- The one who is educated from the wrong books is not educated, he is misled. ----------------------------------------------------------------- [snip] Seppo, it is a bit inconsiderate of you not to point out to Robert that he might find AAX very suitable. Jois ----------------------------- A point in every direction is the same as no point at all. "The Point" > > >>No that is where the misconception lies. HSS is considered to come > > into existence at about 40 -> 35 KY ago. [quoted text clipped - 69 lines] > I have said nothing of the kind at all. Homo Erectus went extinct like > the Neanderthal did. They're dead. So is everybody that lived at that time. Selection and chance have deleted most of the genes of these people Homo Sapians or otherwise. In 100,000 years most of the people that are ancestors of the people alive at that future time will not have left a single gene in the gene pool. Unless you actually know who every independly inherited trait or what have you came from, trying to say that any of these people weren't ancestors is crap. Please note that the modern population doesn't match up well with either HSN or HS in a lot of ways. Evolution hasn't stopped. LCA on everything not a fatal mutation is always becoming more recent. > > you are implying that there were > > unrelated evolutionary centers independently heading toward the [quoted text clipped - 5 lines] > same as you arguing being able to be physically in two different > places simultaneously - it can't happen. Sure but what you don't get is that every thing that can have a different LCA will have a different LCA. They will have come from Africa but you don't know when until you do a hades of a lot of testing because you can't know until you do that testing if some snippet from some older LCA not on your little list is still around. Lost lines have been found in old bodies and more will be. >With either, standing alone, I have to wonder mightily about the SNR. Others probably worry more about the viability of their pet theories (and maybe even theses) extracted from the hissing and popping of that one single, noisy mtDNA channel. It is acceptable today to build theories (or thesis) on very tenuous evidence, or no evidence at all, because in the fossil record the Out of Africa passionate proponents got away with murder. With few, contradictory pieces of bone (Klasies) and partial pieces of a single, dubious cranium (Border Cave), a grandiose theory of transcontinental migrations has been build by which the Levant and Greece (Petralona) has been reclassified as part of Africa and the Cro-Magnon people considered wandering Africans spending the winter vacations in Southern France. In addition, this theory has the Eastern Africans, that couldn't reach Madagascar (even in historical times), speeding up, by bus and boat I guess, to Australia where to frighten the kangaroos reassumed the Homo Erectus attributes of large browridges and low foreheads. Regards. r.c. > >With either, standing alone, I have to wonder mightily about the SNR. > Others probably worry more about the viability of their pet theories [quoted text clipped - 18 lines] > > r.c. I looked at photos on line of the Oldest HS shulls known and one form down under that was historic. The recent one looked like he was kin to the boys from Java with Massive brow ridges and what looked like a large brained but a very similar skull while the guys from Africa didn't match at all. |
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