Comparisons of Neandertal mtDNA with modern humans and modern chimpanzees

I don't mean to whip out logic on you, but what you've done is commit a fallacy called appeal to ignorance.You are basically saying that just because we haven't found a homonid close enough to modern man that such a homonid doesn't exist. Drawing a conclusion from an incomplete record is as ignorant as anyone can get.Edited-wrong info.[This message has been edited Lam, 05-03-2004]

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The Laminator

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More to the point, we do have the remains of such hominids; many of them. Redwolf even mentions some, but his discussion is flawed by various other errors. I'm sure we'll discuss this some more as the thread continues. Neadertal remains have been found more a bit more widely than this. As well as finds in Europe, there are finds in Syria, Israel, Uzbekistan, Morocco and Iraq. Some of these fossils are described at Homo neanderthalensis, at Stephen Heslip's pages at Michigan State University, for a course on Hominid Fossils.Cheers -- Sylas

Really now. My bad.I've always thought they were unique to Europe. Oh well.What about Africa? Has there been findings of them in Africa?

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The Laminator

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Not that I know of. The find at Jebel Irhoud, which is the basis for my listing Morroco in the previous post, would be Africa. It is just across from Gibraltar, but I think the identification with Neandertal may be contentious.The Neandertal range is given by Francis Steen as follows:
{Image is a link to source; uses current browser window}

The source for this map is the same that redwolf used in Message 9 for skull pictures. Seems to be comprehensive and high quality, with copious references to diverse views within the scientific community. Thanks for the reference.Cheers -- Sylas Edit change. The map was previously taken from Neanderthal Sites (by D.S. McDonald). It is now taken from a different source, used by redwolf, and is properly linked.[This message has been edited Sylas, 05-03-2004]

ROFLMAO!To anybody who has followed the argument, the claim and case you made was that neandertals were literally about halfway between humans and chimpanzees and neandertals were not our ancestors (see http://EvC Forum: Aquatic Ape theory? -->EvC Forum: Aquatic Ape theory?); nothing more and nothing less. It wasn't a figure of speech, you argued for its literal truth, and you were flat-out wrong.

More to the point, we do have the remains of such hominids; many of them. Redwolf even mentions some, but his discussion is flawed by various other errors. I'm sure we'll discuss this some more as the thread continues.

Nonetheless, it seems clear enough that that does not save the picture for purposes of evolution.When they used to draw homonid progressions leading up to modern man (which you say you don't like), the final two things before modern man were homo erectus, and neanderthal, it seeming obvious to scientists that the neanderthal was the closest (morphologically) hominid to us, and then erectus, and then the guys further down and back.Depending on whose picture of archaic homo sapiens you use, you are either still trying to claim that modern man descended from something essentially identical to the neanderthal, which has been coercively disproven by the combination of the dna studies and Shreeve's study, or you are trying to claim that something marginally different from us descended from homo erectus, which is a great deal more apelike than the neanderthal, which nobody should believe in light of the recent findings.Moreover, there aren't "many" of these. The one skull in terribly bad shape is said to be the most complete, and they appear to be rare. Too rare for modern man to be descended from them.

I read it better than you, apparently! The very next paragraph after the bit redwolf gives in red reads as follows (my emphasis in bold). Did you read that bit?Yes, I read your link, and the other ones you gave also. You can get all kinds of diverse opinions on this. I have no problem if it turns out that Shreeve disagrees with me, and indeed no problem if there is new evidence that leads me to change my mind. Interbreeding, and interfertility, are still open questions, and the data continues to be collected and examined and tested in various new ways. Shreeve is explicit about this in the end of the article you have quoted: Here are a couple more points you should note.

• Shreeve is a well regarded science writer, but not actually a scientist. He has written some interesting books on Neanderthals, which have been widely praised; but they are not definitive works by any means. They review work by others, and present his own speculations on the matter.
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• Shreeve's own speculations on the lack of interbreeding are that the two species may well have been interfertile, but that interbreeding did not occur because of different mate recognition signals. The argument for this is entirely circumstantial, but worthy of serious consideration. Shreeve himself recognizes this as speculation.
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• The bit you placed in red is not Shreeve's own view, but the way Shreeve describes the views of unnamed German scientists. Shreeve gives no citation and does not name the scientists, but most likely he is referring to Krings et al, whom we have discussed here at some length. The clue is that in the previous page of your link, Shreeve refers to DNA extracted from an arm bone; this is just what Krings et al did. In this case, Shreeve is wrong. The bit that he gives in red does not actually correspond to the views expressed by Krings et al. If you disagree, give a quote from the primary sources. The links are available in Message 1. But don't bother. The truth is that the scientists involved limited their conclusions to the notion that there was no genetic contribution to the gene pool; not that the differences were too great for breeding to be possible. In fact, they gave the comparison with chimpanzee subspecies, suggestive that they were interfertile, even though little to no breeding took place.
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• In your second link, Shreeve does not make a definitive case, but a speculation, by his own description. Quoting from your second link... (my emphasis):
  Although it is merely a speculation, the idea fits some of the facts and solves some of the problems. Certainly the Neanderthals' ancestors were geographically cut off from other populations enough to allow some new mate-recognition system to emerge. During glacial periods, contact through Asia was blocked by the polar glaciers and vast uninhabitable tundra. Mountain glaciers between the Black and Caspian Seas all but completed a barrier to the south. "The Neanderthals are a textbook case for how to get a separate species," archeologist John Shea told me. "Isolate them for 100,000 years, then melt the glaciers and let 'em loose."

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  If mate recognition lay behind a species-level difference between Neanderthals and moderns, the Levantine paradox can finally be put to rest. Their cohabitation with moderns no longer needs explanation. Neanderthals and moderns managed to coexist through long millennia, doing the same humanlike things but without interbreeding, simply because the issue never really came up.
  That is, Shreeve disagrees with your extreme position. He considers that the reason for lack of interbreeding was not lack of fertility, but lack of desire.
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  In fact, your second link is a rather beautiful and thought provoking speculation. I enjoyed it, and it is intriguing to wonder what human history would have been like if our Neandertal cousins had survived.

In the meantime, my extract quoted above remains unambiguously true; it is a straight description of the actual data which we need to consider. The actual empirical data indicates that the genetic difference between Neandertals and Humans was less than the difference between interfertile subspecies of the common chimpanzee, and much less than the difference between common chimpanzee and bonobos, which are also interfertile.Indeed Shreeve mentions this himself, in your first linked article!Shreeve's speculation (not analysis) is an attempt to reconcile the evidence I have cited on comparisons with chimpanzee diversity (which indicated that Neadertals probably were interfertile with Homo sapiens) and the genetic evidence of Krings et al (which suggests that Neadertals did not contribute to the modern gene pool). And even then, Shreeve acknowledges that there is room for future evidence to contribute further understanding. I agree with him on all these three points; and I think his proposed solution, of lack of mate recognition, is very plausible.I think you need to read that article again, and more carefully.Cheers -- Sylas PS. You would be better to remove "?term=" from your link to the first Shreeve article. I have removed it from the URL in the quoted extract from your post. Link construction code here fails to parse the "=" as part of the link. You can also work around the problem by making the links explicitly, rather than leaving a bare URL in your post.

however there have been finds all across the northern and eastern shores of the Med. That would lead me to belive that it is certainly possible if not even likely that we will oneday find examples of Neanderthal habitation along the southern shore of the Med as well.

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Aslan is not a Tame Lion

Another possibility is that the interbred offspring were infertile - mules. This would allow a child or any individual specimen to have mixed DNA, but still no neander DNA in human genome.Personally I have wondered if the temporal overlap between sapiens and neander is the root of the troll and ogre myths. This would shed some light on group interactions. I suppose one could do a search on the location origins of the myths and see if they match the population data to get some inference of validity, but it would be extremely difficult to make more than a hypothetical case.

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we are limited in our ability to understand
by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}

>Did you read that bit?No. I stopped reading at the point of the German scientists claiming that interbreeding would not be possible. I was trying to look at several such articles and was in too much of a hurry.Nonetheless, the one or two skeletons which anybody is making any such claims for could be anything and do not come close to answering the mail for the problem which Shreeve notes, i.e. that you had the two groups living close to eachother for very long periods of time, and that if interbreeding was possible, there should be crossbreed skeletons all over the place; they should be very easy to find.It's also interesting that the one skeleton anybody is claiming as a crossbreed skeleton is that of a child; that may be as long as such crossbreeds ever lived.

Are members allowed to post on the 'proposed new topic' area?

Members can post new topics in Proposed New Topics, but they can't add posts to a thread. Moderators will approve new topics into the appropriate forum, after which all members may join in.For more details, see Message 1 and following, and Message 53. And discussion or comments is being actively solicited, and is very welcome. Please give it in those threads, not in followup to this thread.AdminSylas

I have extended the photo gallery from my previous message: A Cro magnon skull specimen has been added at the front, while Homo habilis and Homo rudolfensis have been added at the end.I have also shown the "calibration" lines that I used to size the pictures in order to take out variation that could be from individual specimens and to show relative proportions.This is in answer to the claim by redwolf\ted that there is a major discontinuity in the family tree (Note that his "archaic" Homo sapiens is now considered Homo heidelbergensis and is shown as such here).Enjoy.ps - ted: the New Proposed Topics is the place to start new topics, see http://EvC Forum: HOW TO START A NEW TOPIC (as of 4/13/04)[This message has been edited RAZD, 05-03-2004]

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we are limited in our ability to understand
by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}

Sorry, I wasn't paying attention. (Maybe I shouldn't have had a Buffy episode on in another window.) Yu N, Jensen-Seaman MI, Chemnick L, Kidd JR, Deinard AS, Ryder O, Kidd KK, Li WH. Low nucleotide diversity in chimpanzees and bonobos.
Genetics. 2003 Aug;164(4):1511-8.There's also data from the chimp genome effort on western and central chimps -- it's the actual source I was using, but it hasn't been published yet. It will be available Real Soon Now.

Sheesh -- get your priorities right. You should always have a Buffy episode on in another window. I have another question, which you or others may be able to help me with. In previous posts, I have assumed that the chimpanzee subspecies are interfertile. However, I can't confirm this; and on checking I could be wrong.It seems that the close similarity indicates to most researchers that hybrids are extremely likely, and if I recall correctly, conservation groups advocate that chimpanzees in captivity should be maintained in their distinct subspecies in order to prevent cross breeding and loss of diversity.Is anyone aware of whether or not there are any confirmed instances of fertile hybrid offspring from any of the chimpanzee subspecies? Are there any populations of distinct subspecies which are in contact with each other, so that interactions across subspecies lines would be possible?Cheers -- Sylas