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    Did Non-Anthropogenic Climate Change Cause Neanderthal Extinction?
    By Helen Barratt | December 10th 2010 06:02 AM | 22 comments | Print | E-mail | Track Comments
    Recent research proposes that 40,000 years ago a series of massive, volcanic eruptions caused drastically cooler, dryer climate change, which was then responsible for driving Neanderthals to extinction. This cleared the way for modern humans to replace them and to later flourish in western Europe and eastern Asia as they do now, until the predicted Anthropogenic Climate Warming (ACW) possibly adversely affects them too one day.

    The Neanderthal is named after the Neandertal valley, which is located about 12 km east of Düsseldorf, Germany and where a fossil was discovered n 1856 which was known as the "Neanderthal skull" or "Neanderthal cranium" in anthropological literature, and the individual reconstructed on the basis of the skull was called the "Neanderthal man".

    Photo of a recontructed face of a Neanderthal child from the Anthropological Institute, University of Zürich
    Researchers Liubov Vitaliena Golovanova and Vladimir Borisovich Doronichev of the ANO Laboratory of Prehistory in St. Petersburg, have offered the hypothesis "(T)hat the Neanderthal demise occurred abruptly(on a geological time-scale) … after the most powerful volcanic activity in western Eurasia during the period of Neanderthal evolutionary history,” the researchers write. “[T]his catastrophe not only drastically destroyed the ecological niches of Neanderthal populations but also caused their mass physical depopulation.”

    There are many Neanderthal extinction hypotheses about how Neanderthals disappeared around 30,000 years ago, and there have also been many heated debates over the years about the Neanderthals' place in the human family tree. At varying, different times they were classified as a separate species Homo neanderthalensis and also as a subspecies of Homo sapiens, called Homo sapiens neanderthalensis.

    “These extinction hypotheses include the inability to cope with climate change, competitive exclusion or even genocide by anatomically modern humans, and hybridization, effectively being absorbed into the Cro-Magnon population.”

    Researchers have also debated whether Neanderthals were an entirely separate species, and recent evidence suggests that they probably weren’t. Some people even question whether Neanderthals are really extinct, as they still live on in our genes, I certainly feel that I’ve met a few Neanderthals in my life, and of course I mean that as a compliment. Recently researchers have produced the first whole genome sequence of the 3 billion letters in the Neanderthal genome, and the initial analysis suggests that up to 2 percent of the DNA in the genome of present-day humans outside of Africa originated in Neanderthals or in Neanderthals' ancestors. See http://www.genome.gov/27539119

    There is evidence that as well as being strong, hairy and predatory, Neanderthals were far from stupid, and were creative, innovative thinkers. Like Homo sapiens, childbirth was also difficult for Neanderthals because they had a brain at birth of a similar size to that of modern-day babies. However, after birth, their brain grew more quickly than it does for Homo sapiens and became larger too and the individual lifespan ran just as slowly as it does for modern human beings. It is estimated that gene flow from Neanderthals to humans first occurred between 80,000 and 50,000 years ago (ScienceDaily May, 2010) .

    The Climate Change hypothesis about Neanderthal extinction proposes that a series of major volcanic eruptions 40,000 years BC, affected the region between Italy and the Caucasus Mountains, and may have drastically reduced the Neanderthals’ food supply and challenged their innovative but primarily predatory hunting skills, as they were possibly carnivorous apex or alpha predators, residing at the top of the food chain though there is recent evidence that suggests that they were omnivorous, either way fewer plants meant less food.

    Golovanova and Doronichev studied the sedimentary layers at Mezmaiskaya Cave in the Caucasus Mountains of southern Russia, which is a site rich in Neanderthal bones and artifacts. These studies suggest a severe reduction of plant pollen at a time corresponding with the volcanic eruptions. This damage to plant life would have caused a drastic corresponding decline in the plant-eating mammals that were hunted by the Neanderthals. It is also an indication of a sudden shift to a much cooler and dryer climate change.

    The second of the two volcanic eruptions coincided with the end of Neanderthal presence at Mezmaiskaya. Many Neanderthal bones, stone tools, and skeletal remains of their prey animals were found in the sedimentary layers beneath the second volcanic ash deposit, but none above it. Modern humans are thought to have also existed in this area and would have been very adversely affected too but if they died out they were replaced later by those Homo sapiens who survived more or less unscathed in Eastern Asia and Southern Africa. These would have then migrated into the vacuum left by the nearly extinct Neanderthals in Eurasia, once the climate conditions had improved.

    The researchers stress that more research data from other areas in Eurasia is needed to support the volcanic climate change hypothesis, however they believe that the Mezmaiskaya cave has delivered some important supporting evidence for the idea of Neanderthal extinction caused by non-anthropogenic climate change.

    Comments

    Amateur Astronomer
    A diet of all meat is not balanced unless the meat is raw. Cooked meet needs a side dish of vegetables and fruit to remain healthy. I wonder if the discovery of cooking with fire had anything to do with the extension. Volcanic eruptions are some of the candidates for help in discovery of cooked meat.
    Bonny Bonobo alias Brat
    Jerry, I think that the main problem for Neanderthal Man was the lack of any kind of meat, fresh or cooked, the secondary problem was probably the lack of nuts and berries all caused by the massive volcanic eruptions, ash cloud and plant unfriendly climate change.
    My article about researchers identifying a potential blue green algae cause & L-Serine treatment for Lou Gehrig's ALS, MND, Parkinsons & Alzheimers is at http://www.science20.com/forums/medicine
    Craig Dillon
    It is a jump to say climate change CAUSED the extinction from it was a FACTOR. If climate change caused it, then how was Neanderthal able to survive previous climate changes? As the area became cooler and dryer, why was the Neanderthal population not able to migrate to warmer wetter areas? It seems to me that the climate change may have added stress, but there were probably other factors that had to be included to force the extinction. Maybe Homo Sapiens occupied areas did not allow Neanderthals to move in. Or, maybe an epidemic added to its problems. Could be many things. I just think its a jump to conclude causality.
    Gerhard Adam
    ... as they were almost exclusively carnivorous apex or alpha predators, residing at the top of the food chain.
    I must've missed this, but what is the basis for asserting that they were carnivores versus omnivores?
    Mundus vult decipi
    Bonny Bonobo alias Brat
    Gerhard I took that from Wikipedia at http://en.wikipedia.org/wiki/Neanderthal_behavior but it appears it may be incorrect, this week there has been a report of a new study showing that
    ‘Neanderthals had a sweet tooth and enjoyed cereals and other carbs, suggests a new study that analyzed food remains that were stuck on and between their teeth’… ‘The study, published in the latest Proceedings of the National Academy of Sciences, adds to the growing body of evidence that Neanderthals weren't just spear-wielding carnivores’.
    My article about researchers identifying a potential blue green algae cause & L-Serine treatment for Lou Gehrig's ALS, MND, Parkinsons & Alzheimers is at http://www.science20.com/forums/medicine
    Gerhard Adam
    I can appreciate that, but I guess my point is that it would seem that a "carnivore" is a very specific definition, which doesn't have any basis as an assertion regarding Neanderthals.  In fact, I would argue that that is a sufficient differentiation to consider them a separate species if it were true.

    Mundus vult decipi
    Bonny Bonobo alias Brat
    Gerhard, according to this study  isotope evidence overwhelmingly points to the Neanderthals behaving as top-level carnivores :-
    “Archeological analysis of faunal remains and of lithic and bone tools has suggested that hunting of medium to large mammals was a major element of Neanderthal subsistence. Plant foods are almost invisible in the archeological record, and it is impossible to estimate accurately their dietary importance. However, stable isotope (δ13C and δ15N) analysis of mammal bone collagen provides a direct measure of diet and has been applied to two Neanderthals and various faunal species from Vindija Cave, Croatia. The isotope evidence overwhelmingly points to the Neanderthals behaving as top-level carnivores, obtaining almost all of their dietary protein from animal sources… Earlier Neanderthals in France and Belgium have yielded similar results, and a pattern of European Neanderthal adaptation as carnivores is emerging. These data reinforce current taphonomic assessments of associated faunal elements and make it unlikely that the Neanderthals were acquiring animal protein principally through scavenging. Instead, these findings portray them as effective predators.”
    My article about researchers identifying a potential blue green algae cause & L-Serine treatment for Lou Gehrig's ALS, MND, Parkinsons & Alzheimers is at http://www.science20.com/forums/medicine
    Gerhard Adam
    Even so, the wording is quite specific referring to dietary protein as coming from animals, while acknowledging that it is impossible to assess the importance of plants in the diet.

    My point is that few animals are truly carnivores and to characterize Neanderthals in that fashion is a quite specific statement.  My guess is that they were omnivorous and capitalized on animal protein when it was plentiful, so that's not surprising, but it doesn't make them carnivores.

    By the way, I do realize that the specific classification is a bit blurry, but I'm trying to be precise when we consider something to be carnivorous versus being omnivorous.   I'm not a big fan of such flexibility in terminology and especially when we're attempting to describe another species or subspecies, I think it's important to consider what these things mean.

    Mundus vult decipi
    Bonny Bonobo alias Brat
    Yes Gerhard I agree and the recent evidence this week shows that at least some Neanderthals were definitely omnivorous, so I have updated the blog accordingly, thanks for your comments.
    My article about researchers identifying a potential blue green algae cause & L-Serine treatment for Lou Gehrig's ALS, MND, Parkinsons & Alzheimers is at http://www.science20.com/forums/medicine
    Steve Davis
    "My point is that few animals are truly carnivores..." Very true Gerhard. My dog often grazes on grass, seeking out the varieties she prefers. These attempts to classify organisms are made by those whose knowledge of animal behaviour does not even extend to pet ownership.
    Bonny Bonobo alias Brat
    Anyway, regardless of whether the Neanderthal was a carnivore or an omnivore, the evidence from this research implies that repeated massive volcanic eruptions in the region adversely affected plant life and everything that depended upon it for its survival, including herbivores, predatory carnivores and even the more versatile omnivores.
    My article about researchers identifying a potential blue green algae cause & L-Serine treatment for Lou Gehrig's ALS, MND, Parkinsons & Alzheimers is at http://www.science20.com/forums/medicine
    Gerhard Adam
    Helen, in all likelihood the Neanderthals were probably just victims of bad luck.  Humans themselves were at an incredibly low population threshold from which they managed to recover and ultimately succeed.  A similar set of circumstances against a comparably small set of Neanderthals that weren't quite so lucky, and extinction becomes highly probable.
    Mundus vult decipi
    Bonny Bonobo alias Brat
    Yes Gerhard, there are so many unknown variables that could have caused the Neanderthals to become extinct but one thing is for sure, luck was not on their side. Even the plant remnants found between their teeth may have resulted from gnawing on plants to assuage their hunger or  from plant medicines taken in a desperate attempt to fight an illness they were suffering from or even from ritualistic placing of plants in dead Neanderthals' mouths, as we know from archeological evidence that they did perform funeral rituals.
    My article about researchers identifying a potential blue green algae cause & L-Serine treatment for Lou Gehrig's ALS, MND, Parkinsons & Alzheimers is at http://www.science20.com/forums/medicine
    The ONLY thing missing in that pic of the Neanderthal kid was the skateboard and the iPod.

    WHO do they think they're kidding!! Neanderthals were bony, fleshy, hairy brutes, and there would have been NO mistaking them or their kids for a homo sapiens!

    Has political correctness now taken over even palaeoanthropology? Is it a THOUGHT CRIME now to call a Neanderthal a primitive and superseded form of human? They RAPED enough of our women to get 4% of their genes into our bloodline, isn't that enough? Now we have to pretend they were gum-chewing, ritalin-popping youngsters afflicted with Playstation thumb found on 4-chan /b/ board?

    Hell, maybe they were... or we are them... or what?!

    Ha ha, very funny!

    A few years ago, I read an interesting, albeit controversial, hypothesis about how the agricultural revolution released significant amounts of CH4, leading to warmer climates. In that case it was actually beneficial to humans because it offset an otherwise naturally cooling trend. This wasn't the article I read originally but it's on the same topic http://www.nature.com/news/2011/110325/full/news.2011.184.html
    Bonny Bonobo alias Brat
    Thanks for the link Enrico, interesting article.
    My article about researchers identifying a potential blue green algae cause & L-Serine treatment for Lou Gehrig's ALS, MND, Parkinsons & Alzheimers is at http://www.science20.com/forums/medicine
    Bonny Bonobo alias Brat
    This week I read that a new study is claiming that Neanderthals died out earlier than originally thought. I also read this week that another study is claiming that they died out much more recently than we previously thought. Both studies are relying on new dating techniques, let's hope they fine tune these dating techniques one day soon.  See http://news.discovery.com/human/neanderthals-may-have-died-out-earlier-than-thought-110509.html#mkcpgn=twnws1 and
    http://news.discovery.com/archaeology/neanderthal-last-stand-tools-ural-mountains-110512.html
    but there are of course many more conflicting Neanderthal extinction studies, these two are probably not even very good examples of how much conflicting evidence there is surrounding this topic. Another study claims that Neanderthals would beat humans in a marathon, this study looks doomed to be proven wrong to me, what do you think?

    Neanderthal vs human skeleton
    Comparison of Neanderthal and Modern Human skeletons.
    (Credit: K. Mowbray, Reconstruction: G. Sawyer and B. Maley, Copyright: Ian Tattersall)
    My article about researchers identifying a potential blue green algae cause & L-Serine treatment for Lou Gehrig's ALS, MND, Parkinsons & Alzheimers is at http://www.science20.com/forums/medicine
    Gerhard Adam
    Another study claims that Neanderthals would beat humans in a marathon...

    "In a short sprint, the Neanderthal might have had a chance, but most fit humans would always win longer races,..."
    http://news.discovery.com/human/humans-would-beat-neanderthals-in-marathon.html
    You got it backwards.  So, do you still think the study is likely wrong?

    I don't see where there are any claims that Neanderthals died out more recently than previous estimates.  In fact, I haven't seen anything that suggest that.  The point of the new dating techniques is that carbon dating is operating at its limits at this range, so by ensuring cleaner samples and reducing/eliminating modern contaminants, the aging become more precise.
    Previously, research teams have provided younger dates which we now know are not robust, possibly because the fossil has become contaminated with more modern particles.
    http://news.discovery.com/human/neanderthals-may-have-died-out-earlier-than-thought-110509.html#mkcpgn=twnws1
    I know more recent claims have been made (in Gibraltar) and may need to be validated with these newer dating techniques.
    http://www.nature.com/nature/journal/v443/n7113/full/nature05195.html

    In general, the point seems to be focused on whether modern humans and Neanderthals could've overlapped and competed in the same environment.  With the dating suggesting that Neanderthals may have become extinct 10,000 years earlier than previously thought, it suggests that humans and Neanderthals had less likelihood of contact (NOTE: This is specific to Europe).
    David Reich, a geneticist at Harvard Medical School in Boston, Massachusetts, says that Higham's conclusion fits with his own team's discovery that all contemporary humans, except those who trace their ancestry to Africa, owe about 1–4% of their DNA to interbreeding between humans and Neanderthals2. Reich's team did not find any proof that Neanderthals ever mated with the ancestors of modern Europeans specifically.
    http://www.nature.com/news/2011/110509/full/news.2011.276.html
    Mundus vult decipi
    Bonny Bonobo alias Brat
    OK, I was being lazy, I'll find the study tonight when I get back.
    My article about researchers identifying a potential blue green algae cause & L-Serine treatment for Lou Gehrig's ALS, MND, Parkinsons & Alzheimers is at http://www.science20.com/forums/medicine
    Bonny Bonobo alias Brat
    Gerhard,  here it is. This study claims that a Neanderthal-style toolkit found in Russia's Ural Mountains dates to 33,000 years ago and may mark the last refuge of Neanderthals before they went extinct. 
    Another possibility is that anatomically modern humans crafted the hefty tools using what's known as Mousterian technology associated with Neanderthals, but anthropologists believe that's unlikely."We consider it overwhelmingly probable that the Mousterian technology we describe was performed by Neanderthals, and thus that they indeed survived longer, that is until 33,000 years ago, than most other scientists believe.
     Project leader Ludovic Slimak said the study suggests "that Neanderthals did not disappear due to climate shifts or cultural inferiority. It is clear that, showing such adaptability, the Mousterian cultures can no longer be considered as archaic." 
    Interesting isn't it, so why did the Neanderthals become extinct (apart from the 1 to 4% Neanderthal genes that live on in non-African descent humans claimed in this article)?
    My article about researchers identifying a potential blue green algae cause & L-Serine treatment for Lou Gehrig's ALS, MND, Parkinsons & Alzheimers is at http://www.science20.com/forums/medicine
    Gerhard Adam
    Helen, the paragraph before the one you quote explains the difference in dates.
    A Neanderthal-style toolkit found in the frigid far north of Russia's Ural Mountains dates to 33,000 years ago and may mark the last refuge of Neanderthals before they went extinct, according to a new Science study.
    Dating artifacts (like a toolkit) is a different enterprise than dating bones from an infant (which is what produced the increased age values). 
    Interesting isn't it, so why did the Neanderthals become extinct (apart from the 1 to 4% Neanderthal genes that live on in non-African descent humans claimed in this article).
    I don't think there's enough evidence to support any particular point of view.  It could be any number of factors that drive a group to extinction and it may never be known.  What often marks this discussion is whether or not there was some coexistence and ultimate conflict with modern humans that gave rise to the extinction.  These changed ages suggest that this is not a plausible scenario (in Europe), since there would have been little or no opportunity for a sufficient overlap in their existence.  Quite frankly it could be as simple as different diseases being introduced by modern humans migrating into Neanderthal areas that rendered them vulnerable (of course this would be irrelevant if they didn't coexist).  Coupled with a slightly lower reproductive rate (or something similar) and Neanderthal extinction would have been all but inevitable.

    If Neanderthals were extinct or on the verge of extinction when modern humans entered Europe, then there could be any number of reasons as to why Neanderthals weren't successful, but the only conclusion that could be reached is that it had nothing to do with modern human migrations.

    I think something that is often overlooked is the fact that even modern humans were seriously threatened for some period with a population that was quite small before a "come-back" enabled them to proliferate.  Any other comparable species that weren't so lucky might never have recovered a sufficient population size to maintain viability.
    The small effective size of mtDNA led to the hypothesis that the human lineage had undergone a recent bottleneck in population size [about 8,800 individuals]. It was suggested that at the time of mtDNA coalescence, the entire human species was limited to one thousand to several thousand individuals (Cann, Stoneking, and Wilson 1987<$REFLINK> ; Vigilant et al. 1991<$REFLINK> ). To account for the mtDNA data, such a bottleneck would have to have been of sufficient duration to allow the fixation by drift of a single ancestral mtDNA variant. Presumably, this bottleneck was followed by expansion to the current population size.
    http://mbe.oxfordjournals.org/content/17/1/2.full

    http://averyremoteperiodindeed.blogspot.com/2010/01/very-low-human-population-size-in-lower.html
    If Neanderthals were larger than humans or required a greater number of calories, then this might've been sufficient to make a difference regarding the opportunities for success even within the same environment.  In any case, the only relevance of the new dating results is in establishing whether modern humans and Neanderthals ever coexisted in a given environment.

    Mundus vult decipi