New evidence of Homo sapiens

Discussion in 'Human Science' started by timojin, Jun 7, 2017.

  1. Fraggle Rocker Staff Member

    Messages:
    24,645
    Okay, but where are the fossils? If they had been migrating through at least two continents, and possibly three, there should be plenty of evidence.
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. sculptor Valued Senior Member

    Messages:
    4,049
    First, see post 32
    then: here is a picture showing locations of findings of (most likely)Heidelbergensis bits and pieces

    Please Register or Log in to view the hidden image!


    and:

    Please Register or Log in to view the hidden image!



    from: https://www.britannica.com/media/full/1159270/76131

    and:
     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. sculptor Valued Senior Member

    Messages:
    4,049
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. sculptor Valued Senior Member

    Messages:
    4,049
    A wrinkle may be offered by many Chinese archaeologists.
    This is most likely a refinement of the multiregional theory which disputes the, more simplistic, out of africa model.
    And, that is, populations of erectus, etc that may have remained in place in refuges(during times of glaciation), then interbred with the waves of migrating cousins during the interglacials, and especially during the superinterglacials.

    see:
    http://www.nature.com/news/how-china-is-rewriting-the-book-on-human-origins-1.20231

    ...............................
    as/re superinterglacials
    Superinterglacial mis 39 most likely occurred during the time of the hypothesized super migrations of erectus.
     
  8. timojin Valued Senior Member

    Messages:
    2,663

    It was a great posting, sculptor
     
    sculptor likes this.
  9. sculptor Valued Senior Member

    Messages:
    4,049
    I've been leaning toward an approximation of that model for quite awhile now.
     
  10. Bells Staff Member

    Messages:
    21,730
    Wow..

    Really sculptor?

    From your link:

    Some Western researchers suggest that there is a hint of nationalism in Chinese palaeontologists' support for continuity. “The Chinese — they do not accept the idea that H. sapiens evolved in Africa,” says one researcher. “They want everything to come from China.”

    Chinese researchers reject such allegations. “This has nothing to do with nationalism,” says Wu. It's all about the evidence — the transitional fossils and archaeological artefacts, he says. “Everything points to continuous evolution in China from H. erectus to modern human.”

    But the continuity-with-hybridization model is countered by overwhelming genetic data that point to Africa as the wellspring of modern humans. Studies of Chinese populations show that 97.4% of their genetic make-up is from ancestral modern humans from Africa, with the rest coming from extinct forms such as Neanderthals and Denisovans5. “If there had been significant contributions from Chinese H. erectus, they would show up in the genetic data,” says Li Hui, a population geneticist at Fudan University in Shanghai. Wu counters that the genetic contribution from archaic hominins in China could have been missed because no DNA has yet been recovered from them.

    Many researchers say that there are ways to explain the existing Asian fossils without resorting to continuity with hybridization. The Zhirendong hominins, for instance, could represent an exodus of early modern humans from Africa between 120,000 and 80,000 years ago. Instead of remaining in the Levant in the Middle East, as was thought previously, these people could have expanded into east Asia, says Michael Petraglia, an archaeologist at the University of Oxford, UK.

    Other evidence backs up this hypothesis: excavations at a cave in Daoxian in China's Hunan province have yielded 47 fossil teeth so modern-looking that they could have come from the mouths of people today. But the fossils are at least 80,000 years old, and perhaps 120,000 years old, Liu and his colleagues reported last year6. “Those early migrants may have interbred with archaic populations along the way or in Asia, which could explain Zhirendong people's primitive traits,” says Petraglia.

    Another possibility is that some of the Chinese fossils, including the Dali skull, represent the mysterious Denisovans, a species identified from Siberian fossils that are more than 40,000 years old. Palaeontologists don't know what the Denisovans looked like, but studies of DNA recovered from their teeth and bones indicate that this ancient population contributed to the genomes of modern humans, especially Australian Aborigines, Papua New Guineans and Polynesians — suggesting that Denisovans might have roamed Asia.

    *Emphasis mine..
     
  11. timojin Valued Senior Member

    Messages:
    2,663
    The textbook is not closed yet, there are more pages, in the future to read.
     
    sculptor likes this.
  12. sculptor Valued Senior Member

    Messages:
    4,049
    Yeh, really,
    or somewhat really
    or well it is one hypothesis
    (it would be a mistake on your part to assume that I believe all of the claims of any individual, or even most of the claims)

    ............
    Fyi:
    I posted that picture because of it's simplicity while showing the heidelbergensis sites requested by fraggle rocker.
    perhaps, this would be more to your liking?

    Please Register or Log in to view the hidden image!



    My primary interest here is/was in the potential northern interglacial migrations. eg if one could expect an overland migration of about 10 miles per generation(which is most likely on the high side) and assume a generation of about 25 years, then in 10,000 years (previously assumed average interglacial), we could expect about a 4000 mile migration in an "average" interglacial. The horn of africa to peking is closer to 5000 miles(imagine the distance of migrations during a 40,000 year super interglacial). We know from european archaeology that extant homo populations retreated to refuges during glacial maxima, then migrated out during warmer periods. This does not mean that all migrations needed the warmth, but it is most likely accurate for migrations into the northern colder climes.

    (rule of thumb) Retreat to refuges = inbreeding, and, most likely genetic mutation via selection for recessive genes. Migration out of refuges = interbreeding and sharing of dna with other migrants (and indigenous populations?)

    In the 60s and 70s(when I took the degrees in anthropology and archaeology) the chinese were claiming that the evidence of the shovel shaped incisors, common in modern chinese and in 500-600,000 year old fossils found in China was proof enough that they were at least partially descended from a continuous indigenous homo population.
    Nationalistic? perhaps
    Does that make it not true?

    Let's take a walk down archaeologies imagination lane.
    The remains of at least 6 homo individuals were found at Gran Dolina, Atapuerca, in Spain. They lived about 800,000 to 1 million years ago and are the oldest human remains found in Europe. Although many experts consider these remains to be part of an early and variable Homo heidelbergensis population, they may also be different enough to be given a new species name Homo antecessor.
    OK
    IF these are indeed Heidelbergensis fossils,(instead of the speculative and ill defined antecessor) then they would be the oldest so defined as heidelbergensis.
    Does that mean that we can categorically state that Heidelbergensis evolved in Spain? Or Europe? Or Eurasia?
    Just because these are the oldest fossils that we know of doesn't really mean anything other than that these are the oldest fossils that we know of. Extrapolating from that to claims of origins may feel comfortable, but goes beyond the bounds of science.

    One maxim holds true for archaeology:
    All of the evidence ain't in yet!

    Keep digging.
     
  13. Bells Staff Member

    Messages:
    21,730
    Heh!..

    I was fairly certain that you did not believe that our hominid ancestors spent a portion of their evolution swimming the oceans (some advocates of the aquatic ape theory even claim that our ancestors swam and existed in the sea for many generations, some even claim they grew gills) before coming back to land as Homo sapiens.. But the link saw my eyebrows raise and a chortle build up..

    I do understand what you were doing, but it was, well, funny and strange all in one.

    I think the issue the Chinese archaeologist who are trying to push for China being the main center of the evolution of H. sapiens is that the genetic data does not support it. And there does seem to be a deeply nationalistic ideology behind it. Could they be correct? Maybe, if they are able to find fossils that support it or explain why, as your own link explains, the DNA of the fossils they have found supports the out of Africa model and not the Chinese model.

    We know there was a interbreeding with other hominids and we also know through our DNA that there were mixtures with various other hominid species, some of which may have evolved from earlier hominid migrations out of Africa, just as we know there were other hominid species in Africa itself that never really went much further. But the DNA evidence supports the origin of H sapiens from Africa and it certainly supports interbreeding with local hominid populations across Europe, the ME and Asia. For example, portions of the Asian population, Polynesians, and Indigenous Australians have Denisova DNA, which points to interbreeding with the local hominid population at some point in time. Just as portions of the European population and that in some parts of Asia, have Neanderthal DNA, which again points to interbreeding at some point in time. But that does not mean that H sapiens evolved in China or parts of Asia, for example. There is not enough evidence to support that theory.

    Some Chinese archaeologists in the article you posted admit that the remains they found could very well be that of the Denisova, as so little is known of them that they are, relatively, unknown to us at this point in time and those remains they are claiming shows that H sapiens evolved in Asia, could very well be that of the Denisova or another yet unknown hominid, because we know that there were various and as yet unknown species of hominids (even parts of our DNA supports this theory)..

    We cannot state anything categorically as yet with Heidelbergensis, because we simply do not know enough about the non Neanderthal hominids that existed in Asia, the ME region, even Africa and Europe, to make any definitive statements. We know some things about Neanderthals, but what we know is minute compared to what we do not know. We do not know about all the other hominid species that existed and unless we have more sheer dumb luck (such as the Naredi discovery in South Africa recently), we won't really know for certain. And I agree with you, we need to keep on digging and never stop digging.

    I do agree with the out of Africa hypothesis, because everything we know so far points to that more than to anything else. I don't agree with timojin's take that we cannot have evolved from people who were black because of his racial hang-up's and I think denying what is known about human evolution because of a racial hang-up is obscene.
     
  14. sculptor Valued Senior Member

    Messages:
    4,049
    The only one I've read pushing that nonsense is that nutjob Jeffrey Kluger.
     
  15. Yazata Valued Senior Member

    Messages:
    4,471
    Accidential double post deleted.
     
    Last edited: Jun 19, 2017 at 5:02 PM
  16. Yazata Valued Senior Member

    Messages:
    4,471
    I tend to think of the physical anthropology of human origins as highly speculative. It's based on (literally) fragmentary evidence, often a few tiny fragments from individual skeletons. Identifying the fragments as hominin isn't always easy. It's typically harder to definitively assign them to particular taxa. There's always controversy about those assignments in the professional literature.

    I agree that the evidence does suggest that the 'out of Africa hypothesis' (note the word 'hypothesis') is most likely correct. But I wouldn't assign it 100% certainty. And there's still question about what came out of Africa and when. It's not morally evil to speculate about the likelihood of alternative possibilities.

    Our currently fragmentary evidence certainly does suggest that the hominin line diverged from the apes in east Africa. Our early ancestors came down from the trees and adopted a bipedal lifestyle in that part of the world. That's where the earliest pre-Homo hominin remains have been found, the Australopithecines and so on.

    It appears that a variety of later pre-modern hominins, Homo erectus and others, left Africa long before anatomically modern humans did. So there appear to have been multiple out-of-Africa episodes. Traces of these earlier varieties of Homo are found all around the world. Some of them might conceivably have originated elsewhere. There may have been back-migrations into Africa. My sense is that human evolutionary history was complicated and may not conform very well to overly simple models.

    I'm skeptical about the idea that earlier hominins stopped evolving for some reason as soon as they left Africa. One would think that reproductive isolation and movement into new ecological habitats would have sped up their evolution (the same way that Darwin hypothesized that his finches evolved new species by colonizing different islands in the Galapagos). Today some people are apparently willing to entertain the idea that these earlier migrants from Africa did keep evolving, but the idea seems to be that everything that evolved outside Africa was abortive and later went extinct. (Neanderthals, Denisovans and Flores island 'hobbits' as just three examples.)

    I just find the idea that all productive human evolution must take place in east Africa, in one evolutionarily favored place, to be unlikely. So while I would agree that the weight of the evidence does seem to favor an 'out-of-Africa' hypothesis for anatomically modern humans, I don't think that it's yet proven 'beyond a reasonable doubt'.

    This latest evidence of anatomically modern (or modernish) humans in Morocco is interesting, since it places them outside east Africa about 300,000 years ago, 150,000 years earlier than our previous earliest examples of early Homo sapiens, and much closer to the hypothetical divergence between our line and the Neanderthals, some 500,000 years ago (an estimate based on genetic evidence). I'm not convinced that anyone can say for sure where that divergence took place. If these early Home sapiens are found in Morocco, one wonders whether they will be discovered in nearby Spain as well. I wouldn't be hugely surprised to see them turning up in the Middle East or South Asia.

    Even if Homo sapiens did originate in Africa (I'm not 100% convinced but it does seem most likely) I'm more skeptical that they left Africa all at one time in a single wave. I'm more inclined to suspect that they probably trickled out using a variety of routes (Sinai, Yemen and likely Spain) over a very extended period in small bands.

    And I'm reasonably sure the DNA from these new Moroccan examples hasn't been sequenced. I'm doubtful whether their DNA has even been recovered. If it has, it's probably so fragmented and so profoundly contaminated with more recent non-human DNA that sequencing it would be exceedingly difficult. (Laypeople greatly overestimate how easy it is to sequence ancient DNA.)

    I don't think that anyone knows what their physical appearance was, apart from some aspects of their skeletal anatomy such as face shape. I'd guess that if we saw them they wouldn't correspond to any of our contemporary stereotypical 'races'. I'm still inclined to speculate that if we think of our contemporary races as an evolutionary radiation from a more homogeneous ancestral type, that the origin will probably be something in the middle of the radiation, a brown skinned individual with black probably straight hair, darker skinned than contemporary white northern Europeans, lighter than contemporary negroes, and without the typical northeast Asian fatty skin layers and eye-folds (obviously cold weather adaptations). We still find people with similar appearance all over the world. Something like this:

    https://s-media-cache-ak0.pinimg.com/originals/8c/ce/ee/8cceee090f3062817813fe1ab21e9c1b.jpg

    A politically motivated individual might insist that this idea is motivated by a desire not to have negroes in other aces ancestry, and hence is "racist" (today's all-purpose term of abuse, like "asshole"). Of course a similarly motivated opponent could argue back that a desire to identify negroes as the trunk of the human tree as opposed to being a later evolutionary-radiation development like everyone else, is an attempt to depict them as being the earliest, most primitive and least evolved among the human varieties, and hence "racist" in its own way. It's probably bullshit either way.
     
    Last edited: Jun 19, 2017 at 6:29 PM
    sculptor likes this.
  17. Bells Staff Member

    Messages:
    21,730
    There is no evidence that they stopped evolving. There is every evidence that there was a form of evolutionary period and that there were various species of hominids that existed, possibly overlapping.. Which would mean that they did continue to evolve but simply failed to survive for long. It could or may very well be an issue where competing for resources against H sapiens saw them die out or perhaps natural events or lower sperm or ovum counts or issues with live births or a variety of other reasons so them become extinct. But we know they were there because groups of people in different regions carrying their DNA. We just do not know which species of hominids they happened to be.

    I also do not think that migration out of Africa was a single event. The dates of fossils outside of Africa, show and indicate that this may very well be the case.
     
  18. timojin Valued Senior Member

    Messages:
    2,663
    [QUOTE="Bells, post: 3462443, member: 4807

    I do agree with the out of Africa hypothesis, because everything we know so far points to that more than to anything else. I don't agree with timojin's take that we cannot have evolved from people who were black because of his racial hang-up's and I think denying what is known about human evolution because of a racial hang-up is obscene.[/QUOTE]

    It is not racial hang up. It the Hypothesis that the melatonin genoma with time will mutate, the lips will increase in size , the nose becomes elongated, the hair from being kinky becomes elongated.
     
  19. Bells Staff Member

    Messages:
    21,730
    What makes you think it did and was not the other way around?

    You need to stop looking at how people look now, and making such comparisons to the first H sapiens.
     
  20. sculptor Valued Senior Member

    Messages:
    4,049
    Speaking of which, have you looked at the brow ridges of the Moroccan "sapiens-sapiens" skull?
    Would you argue that that represents an early modern human? or a transitional stage?
     
  21. timojin Valued Senior Member

    Messages:
    2,663
    I don't have any problem if it would be around as you say.
    Let me put you this way : you line up four persons ( black, yellow, native american and white ) from different region, and than you are asked to identify the individual from which region they come from. Remember all are human.
    You are labeling me as a racist , ok , I assume you are an N zelandian white woman , would you get involved with a non white male ? I as a racist, my children are nonwhite. I have been maried 3 times , one white and two time with nonwhite. At my present sentiment, if other misfortune would come , I would not take a white woman as a partner . Yes, I am a caucasian racist.
     
  22. origin Trump is the best argument against a democracy. Valued Senior Member

    Messages:
    9,448
    No, you are just a racist. As Trump would say - sad!
     
  23. Bells Staff Member

    Messages:
    21,730
    Sculptor

    The 300,000+ year old one that was published in Nature this month?

    I have looked at it and I feel someone dubious about Hublin clumping it as a H. sapiens.. He even admits that it may point to a more primitive form of H. sapiens. They were unable to pull any DNA from the many bone fragments they found to see if any of the remains from that site fall on the H. sapiens lineage.

    Looking at it, it does not seem that different to the Florisbad skull that was found in South African that was dated to around 200,000 years ago.

    Is it a possible archaic H. sapiens or a transitional species of modern human ancestors? Maybe. It is sort of hard to say for certain without any DNA.

    Could it be another species? Maybe..

    Palaeontologist Jeffrey Schwartz, at the University of Pittsburgh, Pennsylvania, says the new finds are important — but he is not convinced that they should be considered H. sapiens. Too many different-looking fossils have been lumped together under the species, he thinks, complicating efforts to interpret new fossils and to come up with scenarios on how, when and where our species emerged.

    Homo sapiens, despite being so well known, was a species without a past until now,” says María Martínon-Torres, a palaeoanthropologist at University College London, noting the scarcity of fossils linked to human origins in Africa. But the lack of features that, she says, define our species — such as a prominent chin and forehead — convince her that the Jebel Irhoud remains should not be considered H. sapiens.

    I kind of agree with them.

    To wit, it is kind of hard to say for certain. But I do think there are too many question marks about these remains to simply declare them to be H. sapiens when they could in fact be something else entirely.

    What is interesting though is just how it shows the spread of archaic human species even throughout the African continent..



    ____________________________________________
    Journals cited:

    J.-J. Hublin et al. "New fossils from Jebel Irhoud, Morocco and the pan-African origin of Homo sapiens". Nature. Published online June 7, 2017. doi:10.1038/nature22336.

    Callaway, Ewen. "Oldest Homo Sapiens Fossil Claim Rewrites Our Species' History." Nature News. Nature Publishing Group, 7 June 2017. Web. 20 June 2017. http://go.nature.com/2r3Ewsi.

    _____________________________________________
    _____________________________________________

    Timojin

    Those features do not exist solely in particular regions.

    For example, Australian Aboriginals and Polynesians will often have blonde hair. Aboriginal Australians will more often than not, have straight hair, sometimes blonde or red. Some Polynesians or Melanesians can have blonde hair and bright piercing blue eyes. Not because of any European ancestry... And to make it even more interesting for you:

    Remember that East and West Eurasians are light skinned for different reasons. And in regards to skin color, an interesting point is that Melanesians, in particular Solomon Islanders, are amongst the most genetically similar to Africans when it comes to variation on these loci. TYRP1 is quite the exception.

    The TYRP1 is the blonde hair gene.. That does not exist in Europeans. It is naturally occurring in Melanesians. Just as blonde and red hair is naturally occurring in Australian Aboriginals. Their ancestors are believed to have migrated out of Africa in an exodus at least 75,000 years ago.. Long before Europeans even arrived in Europe and experienced a lightening of the skin..

    Asian features, also exists in other areas and other continents.

    Black or brown skin is the exact same thing.

    Those features did not exist in particular regions only, and instead, were present in these various populations for thousands of years, and pretty much were always features of those regions..
     

Share This Page