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Author | Topic: New Type of Ancient Human Found—Descendants Live Today? | ||||||||||||||||||||
Jon Inactive Member |
For anyone who might be interested, here is the full (PDF) version of the one of the articles Bluejay cited in one of his previous posts:
Multiregional, Not Multiple Origins by Wolpoff, Hawks, & Caspari. I cannot get the second one; perhaps if he could let me know the title I could find it. Jon Love your enemies!
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Dr Jack Member Posts: 3514 From: Immigrant in the land of Deutsch Joined: Member Rating: 8.3 |
Right, so Wolpoff et al have developed a new, and different, theory that they're still insisting on calling the multi-regional hypothesis. How wonderfully helpful.
At least now we're still more or less on the same page. They don't do a lot of explaining in that paper of what it is they're actually claiming, or what the evidence for it is. But, from what I can gather - yeah, they're still wrong. The overwhelming story of the evolutionary history of Homo sapiens is that it evolved in Africa and then spread to the rest of the world replacing local populations of other Homo species along the way. To a good first approximation that's true; there's a little more to it than that, but that's the big picture. It's not a story of global evolution, but one of local evolution and spread. Wolpoff's bizarre claim that any reticulation renders OoA wrong is just the Bluejay Claim writ large.
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Dr Jack Member Posts: 3514 From: Immigrant in the land of Deutsch Joined: Member Rating: 8.3 |
You found the Wiki! If you prefer I can cite multiple textbooks on evolution, instead. But, frankly, Wiki is easier to link to and has almost precisely the same diagram.
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Jon Inactive Member |
Replies to Message 197
Right, so Wolpoff et al have developed a new, and different, theory that they're still insisting on calling the multi-regional hypothesis. How wonderfully helpful. The book I cited is far from new, and is largely based off of previous work.
They don't do a lot of explaining in that paper of what it is they're actually claiming, or what the evidence for it is. Maybe not; I haven't yet read it fully. It's possible to find papers on any topic that are less than explanatory. This is why I've listed sources that provide a more detailed look into the MH theory as presented by MH proponents. Replies to Message 198 If you prefer I can cite multiple textbooks on evolution, instead. But, frankly, Wiki is easier to link to and has almost precisely the same diagram. Too bad that citing stuff actually written by MH proponents as proof of their views does not appear as one of your options. I can understand your reluctance to find source material supporting your claims, of course: especially if none exists. And seeing as how you've been making the same claims about the MH model and my understanding of it since your first post in this thread (Message 8); and seeing as how you've refused to offer any evidence to support your claims about the MH model and my understanding; I can say I'm no longer interested in your shenanigans. When you come up with a new angle, let me know. Jon Love your enemies!
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Dr Jack Member Posts: 3514 From: Immigrant in the land of Deutsch Joined: Member Rating: 8.3 |
The Cambridge Encyclopaedia of Human Evolution, Steve Jones et al (ed), Cambridge University Press, 1992. p. 390 (and others)
The Human Past, Chris Scarre (ed), Thames and Hudson, 2005, p. 129 (and others)
Human Evolution: A Very Short Introduction, Bernard Wood, Oxford University Press, 2005, p. 104 Do I need to pointlessly hunt out yet more references, or are you going to drop this silliness now? Wikipedia's depiction of the multiregional hypothesis is correct, and exactly as it is widely described in reputable sources. Using a different version of it, and then complaining that we're misrepresenting it is bullshit. Would you like to accurately describe, and then discuss, what it is you're talking about now?
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DBlevins Member (Idle past 3803 days) Posts: 652 From: Puyallup, WA. Joined: |
I am pretty sure that what you are describing about the MRH is a little off, but I might just be misunderstanding you. If I understand you, you seem to be suggesting that the MRH is saying parallel evolution occured without any gene flow. But, anyways, I hope you will forgive me if I have misunderstood .
The MRH proposes that there was enough genetic flow between the populations that they all evolved together into H. sapiens, with local variation in populations. I guess my best analogy would be ring species that maintain enough gene flow that cladogenesis is kept from happening. Iirc it is essentially saying modern humans evolved through anagenesis. Here is the image I was taught, as regards the MRH hypothesis.
(Note the "gene flow" across "species") P.S. I personally have a hard time with the hypothesis, but I have a hard time with the 'strict' OOA as well. Clifford Jolly did some research on hybrid zones between baboon species that had diverged something like 2 million years (i don't recall the exact timeframe but it was quite large) but were still capable of fertile interbreeding. Taken together with the patterns of migration evidenced by the fossils we've found over Europe, Asia, and the Middle East, it seems to me that some amount of gene flow is likely to have taken place, even between species seperated by 100's of thousands of years.
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Dr Jack Member Posts: 3514 From: Immigrant in the land of Deutsch Joined: Member Rating: 8.3 |
Yes, that is what I understand as the (weak) multiregional hypothesis.
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Blue Jay Member (Idle past 2726 days) Posts: 2843 From: You couldn't pronounce it with your mouthparts Joined: |
Hi, Jon.
The links are working for me. Can any lurkers (if there are any) please test the links to see if the troubles are specific to Jon? Jon, can you just cut-and-paste the links from the "peek" mode? Here are the bibliographical references, if that helps:
Wolpoff MH, Hawks J & Caspari R (2000) Multiregional, not multiple origins. American Journal of Physical Anthropology 112(1):129-136.
Wolpoff MH, Spuhler JN, Smith FH, Radovcic J, Pope G, Frayer DW, Eckhardt R & Clark J (1988) Modern human origins. Science 241(4867):772-773. I have to admit that I've only read several peer-reviewed papers by Wolpoff. I've also read a couple other papers by some of the co-authors on those Wolpoff papers, but I can't remember what any of those papers said now. I have not read the book Race and Human Evolution, but I am familiar with the concept and understand his brief arguments about it from the letters I linked to. His way of dealing with it seems to be that, while one would normally expect center-and-edge effects from a mixing population, there are numerous reasons why these effects would not be apparent, which I would refer to as "ad hoc explanations." -Bluejay (a.k.a. Mantis, Thylacosmilus) Darwin loves you.
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fearandloathing Member (Idle past 4173 days) Posts: 990 From: Burlington, NC, USA Joined: |
Hi,
The first link works, I had to load it twice though before I got it, the second wanted me to sign in to view the page....ect
quote: "No sympathy for the devil; keep that in mind. Buy the ticket, take the ride...and if it occasionally gets a little heavier than what you had in mind, well...maybe chalk it off to forced conscious expansion: Tune in, freak out, get beaten." Hunter S. Thompson Ad astra per aspera Nihil curo de ista tua stulta superstitione.
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Blue Jay Member (Idle past 2726 days) Posts: 2843 From: You couldn't pronounce it with your mouthparts Joined: |
Hi, Jon.
I certainly have trouble letting go of a debate: this is the second time I've come back immediately after claiming to be summarizing. Oh well: you're not a bad debate partner, so I don't mind.
Jon writes: Bluejay writes: ...that their genes diffused virtually unmolested throughout all of the world through hybridization while the archaic Africans themselves stayed in Africa. There is nothing in MH about unmolested genes. Agreed. I wasn't presenting a tenet of a hypothesis: I was presenting the physical evidence in human genomes that demonstrates essentially a total African whitewashing of regional gene pools, which has to be incorporated into any hypothesis. -----
Jon writes: MH would predict that the first wave of gene outflow would show up on the peripheries as being highly 'molested'. However, a continued outflow would eventually lead to the central genetic information overtaking the regional genetic information; each outflow would leave behind less peripheral genetic information in its wake, especially if the outflow involved genes carrying beneficial adaptations. These aren't predictions: these are ad hoc apologetics to explain why we don't see the center-and-edge effects that a strict hybridization model would predict. -----
Jon writes: Bluejay writes: There is no conceivable reason why a model that proposes regional adaptations and extensive hybridization would result in such lopsided dominance by haplotypes from Africa. I've mentioned several times in this thread why we would see 'lopsided dominance'. I realize this. My trouble with your explanation is that you haven't yet offered an observed example of this mechanism actually accounting for such a pattern of lopsided dominance in a real-world population. On the other hand, I have provided at least one clear example of a historical migration event resulting in an identical pattern of lopsided dominance. I can certainly think of examples in which hybridization has been observed to feed population turnover, such as with Africanized (killer) honeybees. However, in this example, migration and replacement play a key role---a bigger role than hybridization, actually---in the turnover of the population. And, I predict that the same will be found in all other examples that you might bring to the table, because, rationally, migration is simply a better explanation for massive, unilateral genetic influx than is hybridization. -Bluejay (a.k.a. Mantis, Thylacosmilus) Darwin loves you.
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Jon Inactive Member |
Jon writes: MH would predict that the first wave of gene outflow would show up on the peripheries as being highly 'molested'. However, a continued outflow would eventually lead to the central genetic information overtaking the regional genetic information; each outflow would leave behind less peripheral genetic information in its wake, especially if the outflow involved genes carrying beneficial adaptations. These aren't predictions: these are ad hoc apologetics to explain why we don't see the center-and-edge effects that a strict hybridization model would predict. But we do see center-and-edge effects, we see what those effects are after a couple million years in the works. If you want to address the possible validity of the center and edge hypothesis in explaining past situations, you have to do what I've suggested several times now: look at actual evidence from the past.
Oh well: you're not a bad debate partner, so I don't mind. LOL. Glad to see you think that now JonLove your enemies!
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Blue Jay Member (Idle past 2726 days) Posts: 2843 From: You couldn't pronounce it with your mouthparts Joined: |
Hi, Jon.
Jon writes: But we do see center-and-edge effects, we see what those effects are after a couple million years in the works. Or, in other words, we don't really see center-and-edge effects, because they have been eroded and obscured over a couple million years. I find it curious that the pattern left behind "after a couple million years in the works" looks for all the world like a pattern of near-complete replacement. -----
Jon writes: If you want to address the possible validity of the center and edge hypothesis in explaining past situations, you have to do what I've suggested several times now: look at actual evidence from the past. And, as I've already stated, this comes off as an evasion tactic. I am provided reasons why a given prediction isn't upheld by evidence from modern populations, I am referred to evidence from the past to make my conclusion, I am informed that the evidence from the past may be too sparse to form a solid conclusion, and I am still being told that the evidence does not show an alternative pattern, when, to me, it looks for all the world like it does show that alternative pattern. It all feels like little more than proponents of multiregionalism denying me every possible recourse by which I might falsify it. So, I want to change the focus of the discussion and ask you what evidence would falsify the multiregional hypothesis.-Bluejay (a.k.a. Mantis, Thylacosmilus) Darwin loves you.
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Jon Inactive Member |
Jon writes: But we do see center-and-edge effects, we see what those effects are after a couple million years in the works. Or, in other words, we don't really see center-and-edge effects, because they have been eroded and obscured over a couple million years. No; we do see the effects. We see what we would expect given a couple million of years worth of center-and-edge processes. Now if we want to address how the situation looked earlier on, we have to go digging.
I am informed that the evidence from the past may be too sparse to form a solid conclusion, and I am still being told that the evidence does not show an alternative pattern, when, to me, it looks for all the world like it does show that alternative pattern. The evidence from the past isn't actually all that sparse. Multiregionalism, when it was still the prevailing model, was founded largely on the basis of physical remains. The physical evidence still unequivocally supports MH. The genetic evidence is, as I've already admitted, somewhat ambiguous, but nevertheless in line with a working MH model.
So, I want to change the focus of the discussion and ask you what evidence would falsify the multiregional hypothesis. Thank you for the question. I did lay out one scenario a while ago when Taq asked the same question. Here is my response to Taq:
quote: I can certainly look into developing some others; I don't have easy access to most of my sources anymore, so I'll have to think up some more on my own. JonLove your enemies!
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DBlevins Member (Idle past 3803 days) Posts: 652 From: Puyallup, WA. Joined: |
New study finds that our human ancesters interbred in Africa, roughly 20-60 kya, with another hominin, which had diverged from humans roughly 700 kya:
PNAS RedoOrbit science report
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