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  1. #1
    Monster of the deep Kevin Bonham's Avatar
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    Neanderthals, speciation etc.

    This thread-drifted from "announcement: post quoting", believe it or not. These are the last two posts.

    Quote Originally Posted by Barry Cox
    Quote Originally Posted by chesslover
    I think what happened was climate change in Africa. All of humans came from a common ancestor in the Rif Valley in Africa
    I don't believe climate change is the whole story. Perhaps some freak mutation changing the neural topology also had an effect. The climate in Africa was already different to that in Europe but the neandertals were quickly displaced even in climates (like Nth Europe) which favoured their anatomy. AMH with higher tech clothes and weapons easily competed and won outside their ideal climate.

    Quote Originally Posted by Matthew Sweeney
    There is work on going to determine if AMH and neanderthal were interbreading. If so, then same species, if not, not.
    Interbreeding is not the criterion for speciation but the ability to interbred. Perhaps in the future they may be considered a separate species but at present they are generally not.

    Do you know if a name for this new species (should it eventuate) been proposed?

    I suspect the main reasons for there inclusion in H sapien at present is their anatomical similarities and the recency of their coexistence with AMH.
    Quote Originally Posted by Matthew Sweeney
    Species. A laypersons rule of thumb is if the cross produces fertile offspring , then they are the same species. Unfortunately it is more complicated than that. A high school definition is that the individuals must also have the opportunity under normal natural enviromental conditions to interbreed as well. Without out that opportunity, genetic drift will quickly lead to "infertility" based criteria being satifified.

    It also get messy with individual that are theoretically in the same gene pool but have geographically correlated morphalogical differences over a range of environments. These individuals may/may not interbreed because they don't dig their tail-feathers. This helps speciation to occur.
    Once speciation has begun it is not likely to reverse once the "fertile offspring" test begins to fail. eg. AxB=fertile, BxC=fertile, AxC?fertile.

    How this effects AMH x neanderthal, I don't know, other than to say that mitachondrial DNA studies are underway. The lumping together of all the recent Man Version 1.1, 1.2, 1.3 has traditionally been done because the anatomy of fossiles was the only most important objective point of comparison. Anthropologists, using recovered artifacts and induction, also contribute usefully to the debate. However, molecular genetics is really hot right now. Stay tuned.

  2. #2
    Monster of the deep Kevin Bonham's Avatar
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    As I understand it, the picture with DNA testing is that Neanderthals have been shown to be well outside the genetic range of modern humans, with likely reproductive seperations of hundreds of thousands of years. This is said to be consistent with fossil evidence which places Neanderthals in Europe for at least 200 ky before us louts (AMH) showed up. However there is then the question of how meaningful anatomical differences are.

    Also the interpretation of this evidence still seems to be up in the air - it's not really sufficient to prove species-level distinction on commonly used standards of "species" based on the present incomplete DNA evidence, and in any case it doesn't prove Neanderthals couldn't interbreed. (It's very rare for "different" vertebrate animal species to interbreed with fertile offspring, but in some species concepts it can still happen sometimes. Much more of a problem with plants, where in some cases the whole species concept is in serious disrepute.) Some fossils have been interpreted as Neanderthal - AMH hybrids. There is an enormous lot of detail about all this on http://www.neanderthal-modern.com/ but not being an expert on this stuff I have no idea whether it is a fair summary or not.

    Something I do have some idea what I'm talking about in - taxonomy. There are currently numerous competing species concepts with no one concept having clear superiority. Matt mentions the key problem of groups where A breeds with B and B breeds with C but A doesn't breed with C. This can happen for a range of reasons - genetic inability, physical inability, aversion etc. I don't have any trouble treating these superspecies, species aggregates, whatever as single "species" because even if A can't interbreed directly with C, genetic material can still be transferred between A and C over generations quite easily, provided this is geographically possible. However, using this concept, if B suddenly becomes extinct, then A and C may soon become genetically seperated for good, and speciate. Perhaps either A or C will speciate anyway even if B survives, but there is no reason why it has to happen unless one of the forms becomes reproductively isolated (and again, this can happen in a range of ways).

    What Matt mentions about speciation by aversion is a current hot potato. Parapatric speciation (where two species' geographic ranges run up to each other but don't overlap) and sympatric speciation (where a species develops within the range of a species it splits off from) used to be no-nos but are now well and truly on the agenda. Probably not much of an issue in the neanderthal-AMH case where if there are different species involved, then it seems to be through a long period of geographic isolation.

    It's important to remember that "species" is a label we put on things that exist in nature. But individuals don't always slot neatly into that, eg if a population of species A evolves and becomes species B, there isn't a neat line in the sand that you can draw and say that objectively the switch has just occurred - rather "species" refers to clusters that are easy to recognise after that sort of process has finished.

  3. #3
    Reader in Slood Dynamics Rincewind's Avatar
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    This is all realy off-topic of my original point which is that neadertal and AMH are currently not distinguished at the species boundary. Both are currently classed as H sapien.

    As Kevin points out there is dispute in this are. Some paleoanthropologists thinking there may have been interbreeding between the two, others thinking not. This is mainly based on a fossil evidence where some specimens have displayed features of both andbeen interpreted by some as the result of cross-breeding.

    It seems that neandertals were converging in certian traits with AMH which may have been the result of cross breeding ro may have been just the result of natural selection independant of the AMH.

    Either way, I stand by my original point. There is no established species for neandertals and any cranial capacity is no means to the judge intellectual capacity. Otherwise the Blue Whale would have had us all in its thrall millenia ago.
    So einfach wie möglich, aber nicht einfacher - Albert Einstein

  4. #4
    CC International Master
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    this of course assumes that evoltuion is the way we developed.

    I am still undecided on that. but there are many creationists who would dispute this whole topic, and state that the Bible tells how we as a species came about
    Always do your Best

  5. #5
    Reader in Slood Dynamics Rincewind's Avatar
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    Quote Originally Posted by chesslover
    this of course assumes that evoltuion is the way we developed.

    I am still undecided on that. but there are many creationists who would dispute this whole topic, and state that the Bible tells how we as a species came about
    Creationism is an intellectually bankrupt position.
    So einfach wie möglich, aber nicht einfacher - Albert Einstein

  6. #6
    Account Permanently Banned PHAT's Avatar
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    Quote Originally Posted by Barry Cox
    It seems that neandertals were converging in certian traits with AMH which may have been the result of cross breeding ro may have been just the result of natural selection independant of the AMH.
    Convergent evolution does not, as far as we understand, occur with different gene pools competing for dominance in the same niche. Either one gene pool will be out competed, or the two pools will mix.

    Quote Originally Posted by Barry Cox
    Either way, I stand by my original point. There is no established species for neandertals ...
    I am not disputing that. I am agreeing with you that the area is still being researched. The Out-Of-Africa theoryhas the current upperhand against the All-Together theory. However, that may change.

    Quote Originally Posted by Barry Cox
    ...any cranial capacity is no means to the judge intellectual capacity. Otherwise the Blue Whale would have had us all in its thrall millenia ago.
    Snot the capacity that that matters. It is the "superfluous" grey matter, over and above that required to construct sufficiently suffisticated figments to control the generationation of successful locomotion. ie to facilitate the: fight, flight, feed an f.uck subroutines. The greatest contributing factor to raising the total brain mass is a rise in the physical size of the animal. It is the extra stuff - like our prefrontals - that result in "intelegence".

    The extra brain mass of the Neanderthal may been required control the larger msucule bulk of their bodies. This being so, Neanderthal may well have been about as "smart" as us. In fact, I have a shy idea (Mine!) that individual Neanderthals could have been even smarter than AMH individuals. Their is evidence suggesting that Neanderthals had poor communication/language [and spelling]. If that is so, then individually they must have been pretty smart to be able to have had art and culture. Why? because memic transference of knowledge would have been reduced. Much of our so called "intelegence" is realy "exteligence" - the intelegence of the group as a functioning unit.

  7. #7
    Monster of the deep Kevin Bonham's Avatar
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    Quote Originally Posted by chesslover
    this of course assumes that evoltuion is the way we developed.
    The scientific evidence for this is extremely strong.

    I am still undecided on that. but there are many creationists who would dispute this whole topic, and state that the Bible tells how we as a species came about
    They should see http://www.talkorigins.org/origins/faqs-qa.html for comprehensive and detailed discussion of all major creationist objections to evolution.

    Young Earth Creationism is only tenable if one assumes that every time something contradicts anything in the Bible it must be false, even if it is something they would otherwise happily accept as true. If one is willing to accept the Bible as open to disproof then Young Earth Creationism is indefensible.

  8. #8
    Reader in Slood Dynamics Rincewind's Avatar
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    Quote Originally Posted by Kevin Bonham
    Young Earth Creationism is only tenable if one assumes that every time something contradicts anything in the Bible it must be false, even if it is something they would otherwise happily accept as true. If one is willing to accept the Bible as open to disproof then Young Earth Creationism is indefensible.
    One also has to pretty much assume a world-wide conspiracy amongst pretty much all the sciences.
    So einfach wie möglich, aber nicht einfacher - Albert Einstein

  9. #9
    Monster of the deep Kevin Bonham's Avatar
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    Quote Originally Posted by Barry Cox
    One also has to pretty much assume a world-wide conspiracy amongst pretty much all the sciences.
    How did they find out about that? :shock:

  10. #10
    Reader in Slood Dynamics Rincewind's Avatar
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    Quote Originally Posted by Matthew Sweeney
    Convergent evolution does not, as far as we understand, occur with different gene pools competing for dominance in the same niche. Either one gene pool will be out competed, or the two pools will mix.
    For what ever reason there is fossil evidence that neandertals were mutating towards a more modern anatomy. Some people have interpreted this as evidence of interbreeding. Others have thought that perhaps there was no interbreeding but that the neandertals were evolving features more similar to modern humans. I don't think there is no compelling evidence either way.

    Quote Originally Posted by Matthew Sweeney
    I am not disputing that. I am agreeing with you that the area is still being researched. The Out-Of-Africa theoryhas the current upperhand against the All-Together theory. However, that may change.
    Just about everything is still being researched. Currently they are pertty universally considered the same species but anatomically distinct as a separate race.

    Quote Originally Posted by Matthew Sweeney
    Snot the capacity that that matters. It is the "superfluous" grey matter, over and above that required to construct sufficiently suffisticated figments to control the generationation of successful locomotion. ie to facilitate the: fight, flight, feed an f.uck subroutines. The greatest contributing factor to raising the total brain mass is a rise in the physical size of the animal. It is the extra stuff - like our prefrontals - that result in "intelegence".
    Yes, of course. I was being facetious. However, as you point out the neandertals were heaver than AMH so (at least some of) the extra capacity would have been used up there.

    Quote Originally Posted by Matthew Sweeney
    The extra brain mass of the Neanderthal may been required control the larger msucule bulk of their bodies. This being so, Neanderthal may well have been about as "smart" as us. In fact, I have a shy idea (Mine!) that individual Neanderthals could have been even smarter than AMH individuals. Their is evidence suggesting that Neanderthals had poor communication/language [and spelling]. If that is so, then individually they must have been pretty smart to be able to have had art and culture. Why? because memic transference of knowledge would have been reduced. Much of our so called "intelegence" is realy "exteligence" - the intelegence of the group as a functioning unit.
    Not if you include ability to communicate as a measure of intelligence.

    Something stopped the neandertals from taking the next step. Perhaps the AMH development of higher tech clothing and weapons (missile weapons, perhaps) were the killer app which the neandertals couldn't keep up with. I don't think we know for sure but whatever it was, it was big and probably related to the intelligence and/or ability to communicate of the AMH.
    So einfach wie möglich, aber nicht einfacher - Albert Einstein

  11. #11
    CC International Master Cat's Avatar
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    Neanderthals

    I'm not aware that anyone has been able to obtain Neanderthal DNA. My understanding is that Neanderthals co-existed with Cro-Magnon up until 30,000 years ago. The main anatomical differences were in the larynx, where Cro-Magnon had the more elongated larynx as seen in modern humans. This permitted the development of complex language systems, but more importantly the ability to transmit information from one generation to the next - the accumulation of knowledge. It would have also been of immense benefit in hunting.

    Cro-Magnon also developed more ritualistic behaviour, such as burial and probably quasi-religious beliefs, skin decoration, etc.

  12. #12
    Monster of the deep Kevin Bonham's Avatar
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    Re: Neanderthals

    Quote Originally Posted by David_Richards
    I'm not aware that anyone has been able to obtain Neanderthal DNA.
    If you look at the website I quoted in my first post to this thread, you will become aware.

  13. #13
    CC Grandmaster Garvinator's Avatar
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    Quote Originally Posted by Barry Cox
    Something stopped the neandertals from taking the next step. Perhaps the AMH development of higher tech clothing and weapons (missile weapons, perhaps) were the killer app which the neandertals couldn't keep up with. I don't think we know for sure but whatever it was, it was big and probably related to the intelligence and/or ability to communicate of the AMH.
    hello guys, i didnt realise early on what was being discussed here, but now that I do, I would like to join in this as best I can.

    first of all, why do I have a interest in the origins of species. Well in part it has confirmed why i am a devote atheist as others have said here.

    Now on the topic to which the above quote is directed by barry cox.

    Research has shown that the early human races gained an advantage over other species by being able to walk on two legs. This lead to the ability to use hands and arms for hunting, gathering etc. Also over generations, the early humans gained the ability to make clothes, languages etc. the neandertals race lacked this ability.

    As barry has said in the above quote, something stopped the neandertals from taking the next step. I will attempt to explain what that step could have been and what is the most likely reason.

    As we have said, the latter species, cro magnum et al, gain the ability to make clothes and more developed hunting weapons. this then gave the latter species the ability to hunt more effectively and efficently. Over time this allowed the latter species the ability to grow and become larger as a species, which then helped to lead the neandertals to their extinction.

    Now the most major point has almost been proven- the ice ages. Genetic testing of fossils has shown that, as best as i know, the neandertals race became extinct around the time of an ice age. This combined with the other factors already detailed, lead to the neandertals extinction as a species.

  14. #14
    Account Permanently Banned PHAT's Avatar
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    Quote Originally Posted by ggrayggray
    ... gain the ability to make clothes and more developed hunting weapons. this then gave the latter species the ability to hunt more effectively and efficently...
    At least as important as fire, add string to that list. String has been as under rated as Austrailan Juniorchess players. String: for binding sone to wood, making snares, fishing nets, carrying food and babies (sometimes the same thing), controlling cothing furs and shoes ... A simple tecchnology with huge application.

  15. #15
    Reader in Slood Dynamics Rincewind's Avatar
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    Quote Originally Posted by ggrayggray
    As we have said, the latter species, cro magnum et al, gain the ability to make clothes and more developed hunting weapons. this then gave the latter species the ability to hunt more effectively and efficently. Over time this allowed the latter species the ability to grow and become larger as a species, which then helped to lead the neandertals to their extinction.
    I think you mean "races", not "species", according to current taxonomy they're all H sapien.

    Quote Originally Posted by ggrayggray
    Now the most major point has almost been proven- the ice ages. Genetic testing of fossils has shown that, as best as i know, the neandertals race became extinct around the time of an ice age. This combined with the other factors already detailed, lead to the neandertals extinction as a species.
    The oneset of an Ice Age leading to greater competition for resources could have easily accelerated the extinction of the neandertals. However, why they could not compete for resources as efficiently as the AMH is the question that interests me.
    So einfach wie möglich, aber nicht einfacher - Albert Einstein

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