November 16, 2012

The spears of Homo rhodesiensis

When I saw this image:



... I immediately discarded the news item. I said to myself: if those Canadian researchers can't reproduce a proper way to haft a Paleolithic spear, how can they know anything on the matter? Also I only occasionally comment on pre-Sapiens species and the paper is pay-per-view... so I had all the excuses not to comment. 

But in the end the report may be relevant even if the hafting techniques illustrated in that image are so totally wrong that it makes me angry (you don't tie a knife's edge, the points seem to be actually shaped so the wood goes around the base...)

Jane Wilkins et al., Evidence for Early Hafted Hunting Technology. Science 2012. Pay per view ··> LINK [doi:10.1126/science.1227608]

Abstract

Hafting stone points to spears was an important advance in weaponry for early humans. Multiple lines of evidence indicate that ~500,000-year-old stone points from the archaeological site of Kathu Pan 1 (KP1), South Africa, functioned as spear tips. KP1 points exhibit fracture types diagnostic of impact. Modification near the base of some points is consistent with hafting. Experimental and metric data indicate that the points could function well as spear tips. Shape analysis demonstrates that the smaller retouched points are as symmetrical as larger retouched points, which fits expectations for spear tips. The distribution of edge damage is similar to that in an experimental sample of spear tips and is inconsistent with expectations for cutting or scraping tools. Thus, early humans were manufacturing hafted multicomponent tools ~200,000 years earlier than previously thought.

Raw examples of the points under discussion:




While these 500 millennia-old spears are not directly related to any hominin species, the general context almost necessarily implies that it must be Homo rhodesiensis, which is generally considered the immediate ancestor of Homo sapiens.

See for reference: Late human evolution maps (at my old blog Leherensuge), where I summarize the known paleoanthropology of the evolution of Homo spp. towards our kin and that of Neanderthals.

In synthesis: Homo rhodesiensis lived in Southern and Eastern Africa between c. 800,000 years ago (Saldanha Bay, South Africa) and the eve of our species c. 200,000 years ago (Omo, Ethiopia). Some of the late specimens (Lake Eyasi, Tanzania c. 240,000) are suspect of having transitional features towards us.

Direct sources: Noticias de Prehistoria[es], Eureka Alert.

27 comments:

  1. It is a very nice and quite compelling study, but we need much more evidence in Africa during this time frame.

    As to the early humans involved, as I have mentioned numerous times, to me, the similarities in evolution between Europe, the Levant, and Africa speak to fairly free gene flow - which should be expected in the ~800,000 to ~350,000 ya time frame: largely, there were no barriers. So, I would classify the majority of finds during this time as heidelbergensis.

    Given the known cultural complexity of (especially late) heidelbergensis in Europe, the finds discussed in this paper add to the known cranial similarities now cultural similarities - which is significant. Of course, we still need much more to disentangle what was happening during this time frame over three continents, and where and when it ended in the development of AMHs.

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    1. H. heidelbergensis is something else: only located in Europe and the likely ancestor of Neanderthals. H. rhodesiensis is generally considered a different type. Although, if you ask me, all them can be said to be Homo erectus (senso lato) - but never H. heidelbergensis: that would be subverting all the classification and attributing most unlikely way-too-close relationship of our line with that of Neanderthals. I know this line of thought is popular in some circles but it's not founded on strong science that I can identify anywhere: just Neanderthal fetishism and Eurocentric prejudices.

      While not 100% certain a most likely understanding of the evolution of the genus Homo, in the ergaster branch (what Neanderthals and us share) goes as follow:

      · c. 1 Ma. ago H. ergaster emigrates from Africa with Acheulean technology
      · Not long after that, we detect the first H. rhodesiensis in South Africa and the first H. antecessor (presumed ancestor of H. heidelbergensis and H. neanderthalensis) in Iberia.
      · Since c. 800 Ka ago we witness (in the fossil record) the distinct and parallel expansion of H. heidelbergensis in Europe and H. rhodesiensis in East and Southern Africa. In the intermediate area of West Asia and North Africa we see other specimens that my source describes as "H. erectus" but would better fit in the H. ergaster category (but not apparently in either the H. heidelbergensis nor the H. rhodesiensis ones).
      · Since c. 200 Ka ago we witness the distinct and parallel emergence of the most brainy species ever in the genus Homo: H. neanderthalensis and H. sapiens. As we know, the competition between the two species (and the residuals of previous branches) eventually resolved in our favor.

      There's no much room for ambiguity: H. heidelbergensis only existed in Europe (there are some 7-8 specimens known, depending where you place H. antecessor and such) and H. rhodesiensis only existed in Southern and Eastern Africa (there are some 9-11 specimens known, depending where you put Lake Eyasi and Omo 2). There are also some half a dozen unclassified late Homo ergaster (or "erectus", depending who you read)from North Africa and West Asia which are contemporary of these), and then you have the Hathnora hominin in India, which is probably an evolved Homo heidelbergensis or even a Neanderthal with Acheulean techno-context (big hyper-dolicocephalic low vaulted head, very Neanderthal-like).

      Said all that, it would indeed be nice if beyond the anthropometry we'd have some African archaeogenetics. I'm confident that we will eventually be able to extract DNA from tropical or subtropical remains from those periods but I know it's a challenge. Also there's too much interest in Neanderthals and too little in the Rhodesienses. I hope this changes: Eurocentrism has almost always been a burden on Paleoanthropology, since at least Piltdown!

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  2. "to me, the similarities in evolution between Europe, the Levant, and Africa speak to fairly free gene flow"

    Yo me too. But you'll never get Maju to consider that to be the case.

    "but never H. heidelbergensis: that would be subverting all the classification and attributing most unlikely way-too-close relationship of our line with that of Neanderthals".

    Maju. The more information we get the more we see that Neanderthals were not so different from us, genetically, technologically and even culturally.

    "In the intermediate area of West Asia and North Africa we see other specimens that my source describes as 'H. erectus'"

    Almost certainly intermediate between European H. antecessor and African H. rhodesiensis. The only reason they are still called 'H. erectus' is because that would lead to an unacceptably huge, and unrealistic, proliferation of pre-modern human species.

    "There are also some half a dozen unclassified late Homo ergaster (or 'erectus', depending who you read)from North Africa and West Asia which are contemporary of these), and then you have the Hathnora hominin in India"

    Are you really prepared to assign each of these populations a separate species classification? Come on, Maju.

    "Since c. 200 Ka ago we witness the distinct and parallel emergence of the most brainy species ever in the genus Homo: H. neanderthalensis and H. sapiens"

    In this case the 'parallel emergence' is most reasonably explained as being the product of gene flow, not parallel evolution.

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  3. Oh dear. Here we go again. I know in advance that there is no way you're going to agree with the author but I just reached this link via your blog:

    https://blogs.wellesley.edu/vanarsdale/2012/11/17/fossils/my-talk-at-the-aaas/

    Quote:

    "The active production of genetic knowledge relating Neandertals and living and recent human populations, in particular, poses challenges to the commonly held view of Neandertals as a reproductively-isolated biological species, distinct from living humans and our immediate ancestors".

    And more:

    "In other words, if you use the Neandertal-human comparison as a threshold value, basically outlining the limits of morphological/temporal divergence, the results support only a small number of hominin lineages in the Pleistocene, smaller than most traditional views hold".

    And:

    "First, I point out that while time had only a small impact on the pattern of morphological variability, within constrained time comparisons, geographic displacement had a more significant impact".

    In other words, all these Homo 'species' are just geographic subspecies. The same as most other widespread species.

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  4. Have you guys ever heard of "convergent evolution"? There are not such "similarities" in the evolution of Neanderthals and Sapiens lines. Only in one element which is highly adaptive: brains. In body plan we are closer to H. erectus than to Neanderthals for example, while in head plan Neanderthals are much closer to our common ancestors than we are (we have a pretty unique head structure among Homo sp.)

    Also there are modern human distinct populations like Khoisans who have diverged from the rest for maybe 150,000 years and yet are almost identical to the rest of us. Instead look at Neanderthals with their fantasy dwarf body plan (short legs and short forearms, hyper-strong, hyper-compact and with a head shape that only connects with ours via H. erectus).

    The only similitude is brain size and that is a highly adaptive feature, being caused by either convergent evolution (on a very similar quasi-deterministic genetic foundations, after all all Homo branches show growing brains over time) or genetic introgression (which is minimal gene flow of only the highly adaptive genes through buffer populations and not "free gene flow").

    In some 200,000 years of Homo sapiens we don't see (before the age of long distance travel) much "free gene flow". Only at regional levels. For example, Europeans have minor African admixture but it can be totally attributed to North Africa (or Arabian) mediation. In parts of Africa we do see gene flow from Eurasia but it often means almost complete replacement (North Africa), while in most of Africa this backflow is effectively nonexistent.

    So introgression? Maybe, realistic (but independent evolution into "similar" models is also very plausible). "Free gene flow"? Essentially impossible: most unrealistic.

    As for what Van Aardsdale says, it seems all based on "molecular-clock-o-logy", which is extremely misleading. I have good reasons to think that the dates offered by MC fanatics passing by scholars on the Neanderthal-Sapiens divergence are absurdly, ridiculously, nonsensically short. IF, as it's extremely probable, the Denisovan mtDNA is a line from the Asian H. erectus, then the Sapiens-Neanderthal divergence is from c. 1 Ma ago, totally in line with the Atapuerca model.

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  5. Maju,

    Just a couple of points. Firstly, heidelbergensis is the only group for which a transition from small erectus-type brain size to that of modern humans has been fully and continuously documented over time. We know, from fewer data points, that the same transition occurred during the same general time frame in Africa. Unless you believe in some unprecedented parallel-evolution magic and discount all the craniometric PCA analyses, you must come to the conclusion of substantial gene flow if not acknowledging these were essentially the same people.

    Secondly, the lead author herself refers to the people responsible for this (presumably novel) hafting technology as likely heidelbergensis.

    Finally, heidelbergensis is not just some brief period too short to deserve a classification. It ranges over ~650,000 years - much longer than Neanderthal or AMHs, where between about 800,000 ya and 600,000 ya you have the transition from European erectus (ergaster, antecessor), and from ~300,000 to 150,000 ya the transition to fully-fledged Neanderthals (but later in SE Europe, and leaving a full ~300,000-450,000 core years with grey areas to either side). Now, recently, some heidelbergensis-deniers have turned the tables and simply claimed that Neanderthal-like features are seen as early as 600,000 to 800,000 ya. Duh! That's certainly a very political spin on facts. Just make everything post 800,000 ya Neanderthal-like, and ignore that not only the life-span of heidelbergensis is 2-4 times longer than that of Neanderthals, but also the existence of their brethren in SE Europe, SW Asia, and Africa - which cannot be said for Neanderthals in most of those regions except for mere blinks of time.

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    1. I disagree with your evaluation of brain growth, which is also documented, for example, in the H. erectus of East Asia (the various H. ergaster/erectus specimens of North Africa and West Asia were never described as distinct species but surely show also the same general tendency).

      The big jump in brain size (always somewhat relative) only happened with the transition to Homo sapiens and H. neanderthalensis (and Hathnora), i.e. c. 200 Ka ago. Late erectus/ergaster, as well as rhodesiensis and heidelbergensis have somewhat larger brain sizes than earlier erectus on average but the jump in a million and a half years is from c. 900 cm² (max., c. 850 cm² avg) 1.6 Ma ago to c. 1000 cm² (max) since maybe as early as 1 Ma ago (and a similar average as before).

      There's not a single specimen of all those archaic humans (i.e. excepting us, Neanderthals and Hathnora) that reaches the 1000 cm² of brain capacity: not 1.8 Ma ago and not 200 Ma ago. But they also have in general rather large brains, almost invariably above 800 cm².

      So there is a first marked jump in brain size with the advent of the Homo genus. Then a gradual but tenuous increase in size and then two parallel (but also different in may aspects) marked jumps in Africa and Europe (H. sapiens and H. neanderthalensis). What in that period caused that increase? I can't say but surely increased environmental pressure helped quite a bit by means of quelling of all those with less than optimal qualities in the intra-species (or intra-genus) competition.

      But the reasons are not as important as the facts: we do not see any sort of interaction between the line leading to Neanderthals (H. ergaster > antecessor > heidelbergensis > neanderthalensis) and the line leading to us (H. ergaster > rhodesiensis > sapiens), neither in the archaeological nor in any other empirical field of evidence.

      All the rest is mere speculation.

      "... the lead author herself refers to the people responsible for this (presumably novel) hafting technology as likely heidelbergensis"...

      In the paper they talk of H. rhodesiensis. Now, if one assumes that rhodesiensis and heidelbergensis are the same thing (what makes no sense) then you end up saying that kind of things, like Saldanha man being a "heidelbergensis" before any other and so on (conceptual madness).

      "Now, recently, some heidelbergensis-deniers have turned the tables and simply claimed that Neanderthal-like features are seen as early as 600,000 to 800,000 ya".

      Excuse me, sir, but that has been the mainstream model all the time: H. heidelbergensis is proto-Neanderthal (and not proto-Sapiens). Is not "heidelbergensis-denial", as you call it, but confirmation of their well known evolutionary position as proto-neanderthals.

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  6. In some 200,000 years of Homo sapiens we don't see (before the age of long distance travel) much "free gene flow".

    That's because of climate. Between about 650,000 and 270,000 ya, there were only a couple of short cold and dry intervals (~440,000 and ~360,000 ya) - for much of the time the climate was decent, sometimes even subtropical in North-Central Europe, and with a functioning bridge to Africa. During the cold phase ~130,000 to 180,000 ya, Neanderthals had already fully cold-adapted and gene flow was clearly much restricted.

    And as recent results have shown, there was apparently significant gene flow between Eastern Siberians/ Beringians and Europeans between 10,000 - 25,000 ya despite marginal climatic conditions. And of course huge gene flow between Central and South Asians and Europeans - all within a miniscule amount of time.

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    1. "That's because of climate".

      Nah! That's because you need a excuse. If you could at least post some sources...

      AFAIK the Sahara was there all the time (since some 5 Ma ago) except for some pluvial interludes, and you can't forget the Mediterranean Sea (also an important barrier).

      But notably we can see the fossil record of the specimens in the "buffer zone" (and some even in Europe itself) still outside the H. heidelbergensis force-fed conjecture (and also apart from H. rhodesiensis). So both species did not have apparent contact that we can use as foundation for a single-species theory. Hence the single-species model is built on thin air.

      "... significant gene flow between Eastern Siberians/ Beringians and Europeans between 10,000 - 25,000"...

      Do you mean Dienekes' experiments? I won't say that they are totally wrong because obviously the Finnish-like genetics come from over there (but not necessarily in the time-frame you say: just another MC pseudoscientific speculation) but I think that his results are inflated by his ideological "need" to deny African admixture in Europeans. It's not peer-reviewed academic science in any case, so very far from being "evidence".

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  7. "Have you guys ever heard of 'convergent evolution'?"

    Of course we have. And, just to make sure you know yourself what it is:

    http://en.wikipedia.org/wiki/Convergent_evolution

    Quote:

    "Convergent evolution describes the acquisition of the same biological trait in unrelated lineages. The wing is a classic example of convergent evolution in action. Flying insects, birds, and bats have all evolved the capacity of flight independently. They have 'converged' on this useful trait".

    Note: 'unrelated lineages'. It's very unlikely we're dealing here with convergent evolution. Have you ever heard of 'gene flow'?

    "Only in one element which is highly adaptive: brains".

    And the enlarged brain in Homo species across space and time is far more likely to have been the product of gene flow rather than being an example of convergent evolution.

    "Also there are modern human distinct populations like Khoisans who have diverged from the rest for maybe 150,000 years and yet are almost identical to the rest of us".

    As a result of gene flow. We know such has happened because the Khoisan contain such haplogroups as Y-DNA E and mt-DNA L3.

    "after all all Homo branches show growing brains over time"

    As a result of gene flow.

    "In some 200,000 years of Homo sapiens we don't see (before the age of long distance travel) much 'free gene flow'. Only at regional levels".

    Exactly. That's why we see regional variation. Certain genes failed to reach populations at the margins, such as Neanderthals. I would have thought that was simple to see.

    "The big jump in brain size (always somewhat relative) only happened with the transition to Homo sapiens and H. neanderthalensis (and Hathnora), i.e. c. 200 Ka ago. Late erectus/ergaster, as well as rhodesiensis and heidelbergensis have somewhat larger brain sizes than earlier erectus on average but the jump in a million and a half years is from c. 900 cm² (max., c. 850 cm² avg) 1.6 Ma ago to c. 1000 cm² (max) since maybe as early as 1 Ma ago"

    Easily explained, as I have just shown. The gene flow that led to the last period of increased brain size did not reach East and SE Asian H. erectus.

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  8. "Now, if one assumes that rhodesiensis and heidelbergensis are the same thing (what makes no sense)"

    Makes complete sense if rhodesiensis is seen as the African regional variation of heidelbergensis, surely.

    "but independent evolution into 'similar' models is also very plausible"

    Not without massaging the evidence to fit a preconceived belief.

    "As for what Van Aardsdale says, it seems all based on 'molecular-clock-o-logy', which is extremely misleading".

    It is not based at all on molecular clockology. Your claim is based simply on the fact that you need a excuse to ignore what Van Aardsdale says.

    "I have good reasons to think that the dates offered by MC fanatics passing by scholars on the Neanderthal-Sapiens divergence are absurdly, ridiculously, nonsensically short".

    And that would make absolutely no difference to the conclusions Van Aardsdale comes to.

    "Unless you believe in some unprecedented parallel-evolution magic and discount all the craniometric PCA analyses"

    Maju absolutely believes in that. It is a product of the exclusivity and elitism that underpins his whole belief system. It explains his clinging to a 'Garden of Eden syndrome' (a single pair at the origin of all species, and even for populations within each species) and his 'Exodus syndrome' (the eventual mass migration of the descendants of that pair from their Garden of Eden).

    That's not how it happens in reality. Individual advantageous genes spread through members of a population who are in genetic contact with each other. The combination of genes that separate 'modern humans' from their ancestors did not all originate in a single small population confined to a single small region. The combination is a product of a complex pattern of genetic change in a widespread population. A situation that led to a friend coining the expression 'the wave theory of evolution'. And a situation that is becoming more widespread through the scientific community as more evidence accumulates.

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  9. Maju,

    I don't believe in much genetic contribution of Neanderthals to modern humans. Some, for sure, and likely several different ones in addition to Densisovans and others in East Asia. But that is not the point, here. During that time, there were strong climatic reasons for isolation.

    On the flip side, you have erectus coming out of Africa, and then 800,000 to 1,000,000 years later antecessor & ergaster not looking all that much different from each other - but very different from Asian erectus. Either there was a lot of gene flow, or another migration, or both. Then again the same during heidelbergensis. At one point, looking at this evidence, it becomes clear that when climatic conditions were OK (most of the time), there was significant gene flow between Africa, W Asia, and Europe - and it would be foolish to think this was a one-way street, only (rather, direction probably depended on which side was the greenest for something as little as a few hundred years before - enough to multiply the population by 1,000 and more).

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    1. I look and look again at the skulls (erectus, ergaster, heidelbergensis, rhodesiensis...) and they are all similar... and that's why earlier only one catch-all category was used: H. erectus. The differences are not more significant than those among modern humans.

      You are not providing any evidence that "climatic conditions were OK ... most of the time" or that "there was significant gene flow between Africa, W Asia, and Europe". All that is your speculation. In what regards to me: the Sahara is quite older than the genus Homo and has always or almost always been a significant barrier to gene flow, as was the Mediterranean Sea.

      Regardless of all that, you are providing no evidence whatsoever of all your claims on craniometry or whatever (remember anyhow that PCAs are bidimensional, while craniometric measures are multidimensional, so much depends on weights attributed to each, and therefore just indicative).

      "... it would be foolish to think this was a one-way street"...

      I don't say it is the case but we are perfectly familiar with "one way streets", for example Homo sapiens out-of-Africa (some backflow but limited and almost only to the "buffer zone" of North Africa, no known Neanderthal flow in any case), Eurasian Homo sapiens into North Africa, or Australasia (no relevant backflow detected except probably in Philippines), or America... twice (no relevant backflow before the late 20th century), etc.

      If H. ergaster was culturally more advanced than H. erectus (as the use of Acheulean technology may indicate, suggesting also slightly superior cognitive abilities), it is only logical that it was involved in one of those "one way streets". Also the successive OoA bottlenecks generally favored those remaining in Africa because they retained the greatest diversity by far, which is usually the greatest adaptive advantage of all, specially in the long run. Of course nothing is written on stone but chances are like I say.

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  10. "I look and look again at the skulls (erectus, ergaster, heidelbergensis, rhodesiensis...) and they are all similar... and that's why earlier only one catch-all category was used: H. erectus".

    Yes. All similar, especially heidelbergensis and rhodesiensis. These last two species are different from H. erectus, as Eurologist said:

    "antecessor & ergaster not looking all that much different from each other - but very different from Asian erectus".

    You cannot use Homo erectus for those later 'human' species.

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  11. Maju,

    If you compare the analysis of M. W. Blome et al. (Journal of Human Evolution Volume 62, Issue 5, May 2012, Pages 563–592; http://dx.doi.org/10.1016/j.jhevol.2012.01.011) to ice core data on temperature and humidity (i.e. lack of dust; http://upload.wikimedia.org/wikipedia/commons/thumb/b/b8/Vostok_Petit_data.svg/800px-Vostok_Petit_data.svg.png ), you can see that there is a very good correlation in the 150,000 to 30,000 ya time frame in North Africa and the Levant. East Africa is similar but also a bit different in that it has additional wet times. This is a pretty long and varied time, so I think it is a good first order approximation to extend these results to earlier ice core data. For example, in the past 400,000 years you can see that temperatures were often as mild as in the above subset, and often more humid (less dust). "Green Sahara" (and, by extension, "green Levant and Arabia") clearly is a very common occurrence during mild times, and sometimes during the transition periods to and away from warm times. The ~50,000 year period around ~400,000 ya is particularly noteworthy in that it was even subtropical and humid in central-northern Europe - although just before then (<450,000 ya), it was brutally cold.

    As to heidelbergensis, while I do not agree with everything, a good recent review paper is that by Chris Stringer (Evolutionary Anthropology 21:101–107 (2012)). I should note that much work over the past three or four decades unfortunately muddied the waters, while consensus seems to now - with much better data and methods - again go back to what most European mainland researchers thought all along (but not the Anglo-American school).

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    1. Vale, thanks for the references. Sadly I cannot comment unless I read them first, hence, I'd ask you to send me copies to my email (lialdamiz[at]gmail[dot]com). Thanks in advance.

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  12. Papers sent.

    I have adhered to the viewpoint that European, African, and perhaps late East Asian sites/finds can be reasonably grouped into heidelbergensis - who first can be identified most clearly around ~600,000 ya and stuck around to 300,000 - 200,000 ya (from west to east), likely even longer in Asia. While they are evidently related to African erectus (ergaster), I think you would have been easily able to call them apart - 2-D images of skulls can be deceiving:
    http://upload.wikimedia.org/wikipedia/commons/thumb/c/cb/Homo_erectus_new.JPG/480px-Homo_erectus_new.JPG
    http://e-ducation.net/images4/homo.rhodesiensis.jpg
    ;)

    At any rate, the question is where they came from, and was there significant bi-directional gene flow between Europe, West Asia, and Africa. Of course, the most simplistic argument is that their origin is, as always, Africa. However, when looking at the record, one of my problems is that Africa always retains a variety of contemporaneous but much more ancient subspecies, while for some reason Europe/ the Levant always gets the "latest and greatest new model" - starting from the Georgian erectus, to antecessor, heidelbergensis, and then Levantine early AMHs. To me this indicates that these crossroads may have been, at least at times, instrumental in carrying genetic innovations bidirectionally, and the NE of Africa (with some connections to SA) harbored the "latest and greatest" for a reason: the connection to another world of challenges.

    Perhaps at one point it can be demonstrated that the heidelbergensis innovations in features, brain volume, and culture first occurred in Africa and then radiated to Europe. Current datings and brain volume determinations don't indicated this to me, at all - rather, there seems to be co-evolution, from the few data points we have. However, I have no problem with the notion that such exchange terminated from West Europe before ~350,000 ya, and from West Asia ~180,000 ya. Such a scenario can be supported by climate data, and is still consistent with genetic analyses of separation of modern humans from Neanderthals and Denisovans.

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    1. As I told you already, I have received both papers. Thanks again.

      The one on climate (Blome 2012) is most interesting but totally irrelevant for the matter at hand: in all the paper they only discuss the climate of Africa from 150,000 years ago onwards, so I am still scratching my head on how did you imagine this study could help in the debate at hand.

      The other study (or more like narcissist exposition, Stringer 2012) says much about Stringer and his (way-too-influential) school but lacks substance. Essentially Stringer seems to have rechristened Homo ergaster (and descendants) into Homo heidelbergensis and the most common Homo heidelbergensis like Miguelón (SH) or Steinheim into Proto-Neanderthal without a clear nomenclature. He's even challenging the dates for Miguelón, which is considered from stratigraphy to belong to the 500-600 Ka bracket and not to the 350 Ka point calculated with the U/Th isotope tech, which is not able to measure anything older apparently.

      The more I cross my path with Stringer the more I dislike him, sincerely. He's so horribly arrogant and one-sided!

      But influential, very influential... too influential for someone with such a narrow egocentric vision.

      Whatever the case, the paper is not too systematic but more like a preliminary introduction for uni freshmen. Only four specimens are compared visually, of which the H. erectus is a very old peripheral Asian specimen (Sangiran) and (2) the H. sapiens is an Europid (when an African skull would surely be best for comparison). It gives the impression of comparing apples and oranges, like happens with your reconstructions (BTW, white native Southern Africans?, WTF!)

      In any case it's not any sort of complete analysis that could persuade anyone.

      Also his molecular-cloc-o-logic "support" is completely misleading - even accepting the MC hypothesis, it should be (1) upper range is the minimal range (because Pan-Homo split is >8 Ma and not 5-8 Ma as he claims) and (2) the realistic estimate would be double (Dienekes has written extensively about that recently, following some relevant papers - you know, don't you?). That would leave an MC est. Neanderthal-Sapiens split of >800 Ka., which is consistent with the Atapuerca model (mine too) and not Stringer's (yours).

      Finally Stringer produces not a single archaeological evidence in terms of techno-cultural sites and/or currents that could support his late date hypothesis for a third OoA (or first and only "back-to-Africa"?) migration. There's nothing of that kind in fact between the Acheulean OoA, where I place the split between the pre-Neanderthal and pre-Sapiens branches, and the MSA OoA of our fully formed Homo sapiens species.

      There's nothing at all: Stringer knows it and therefore he remains silent.

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    2. "one of my problems is that Africa always retains a variety of contemporaneous but much more ancient subspecies, while for some reason Europe/ the Levant always gets the "latest and greatest new model" - starting from the Georgian erectus, to antecessor"...

      I fail to see how H. georgicus, which is even debated if is erectus at all or a mere H. habilis, can be the "latest and greatest new model". He seems a peripheral erratic to me, probably not even directly the ancestor of Asian H. erectus.

      H. antecessor is not too striking in my opinion. If you'd ask me I'd say: just another ergaster (or "erectus" s.l.). It is anyhow contemporary with the first known H. rhodesiensis (Saldanha man) and with many other undefined H. ergaster which are probably similar in most aspects to both.

      Actually I'm all for recycling Stringer's idea but to talk of H. ergaster instead of the confusing "heidelbergensis". We can talk of H. ergaster pre-neanderthalensis in much of Europe, H. ergaster pre-sapiens in parts of Africa and H. ergaster without label in all other cases. It's a very legitimate approach and one that really seems supported by the factual evidence. Also, using H. ergaster instead of H. erectus we get rid of the confusing East Asian branch and the earliest less developed African remains as well, simplifying the discussion frame to H. ergaster and its varieties.

      But I won't accept "heidelbergensis" because it normally refers only to a handful of European pre-Neanderthal remains, whatever that narcissistic Stringer says. There is absolutely no evidence than anything that cannot be classified as H. ergaster with Acheulean technology ever migrated between Africa and West Eurasia or vice versa between the earlier H. erectus/habilis and the later H. sapiens flows.

      Delete
  13. The one on climate (Blome 2012) is most interesting but totally irrelevant for the matter at hand: in all the paper they only discuss the climate of Africa from 150,000 years ago onwards, so I am still scratching my head on how did you imagine this study could help in the debate at hand.

    My point was that there is reasonable correlation with ice core data - in particular, even with the less well-suited Antarctic data, that albeit have the advantage of going further back. My second point was that overall, "greening" conditions were prevalent and ubiquitous. Not every time and all the time the entire Sahara or even huge portions of it, but sufficient to make a wide corridor along the Nile and westward interior and along the cost, and for significant population increases in N & NE Africa, the Levant, and Arabia.

    As to Stringer, this is a review article - not original research. It is IMO still close to being a majority viewpoint, these days - even though he is overly cautious and diplomatic in some segments.

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    1. Notice that the period covered by the climate study includes both latest Pluvials:

      1. The Abbassia Pluvial, which Bloma makes last the whole MIS 5 stadial but that is more commonly said to be somewhat shorter and much more fragmented. For example, when I reviewed Rose's paper on the Nubian culture in Dhofar, I found that the MIS 5 can be divided as follows:

      MIS 5a - 84-74 (wet)
      MIS 5b - 92-84 (?)
      MIS 5c - 105-92 (wet)
      MIS 5d - 115-105 (?)
      MIS 5e - 130-115 (very wet and warm: Eemian interglacial)

      For whatever reason, migrations in Arabia seem concentrated in the MIS 5e (southern or "coastal": Rose, Armitage - also the Galilee skulls possibly) and the MIS 5b periods (northern or "riverine", Petraglia).

      "It is IMO still close to being a majority viewpoint"...

      Sadly enough. Some people, specially some with anglosaxon surnames, are too influential for the good of Humankind.

      He's simply wrong and has no factual evidence: nothing in what he says makes the slightest sense from an holistic, comprehensive viewpoint. It's totally fragmentary and exclusively anthropometrical speculation: no cultural archaeology, not even a plausible model, never mind the MC rantings.

      Delete
    2. Oops I left the first part of my reply cut.

      I should have followed more or less like this:

      2. Mousterian Pluvial (shorter).

      Both take up some 70 of the 100 millennia covered in the study. But that's not normal and sub-periods should be considered also, as we can see in the Arabian case.

      It'd be interesting if you'd resuscitated that blog of yours and wrote an entry with nice graphs (cut and paste and write down some notes, should not be too hard) on how you extrapolate these two Pluvials to the remote past based on Greenland cores' data. Meanwhile, never having read any single paper on how was the Sahara between its formation and the Abbassia pluvial (something about the Nile formation but little more), I remain skeptic.

      Also how (if at all) do you relate Acheulean → Mousterian with Acheulean → Sangoan → MSA, which is the critical aspect because all the rest is nothing but conflating the brain size of some co-evolving skulls in remotely distant parts of the globe like South Africa and Spain.

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    3. Erratum: not "co-evolving" but "parallelly evolving", which is not the same at all. Sorry.

      Delete
  14. Actually I'm all for recycling Stringer's idea but to talk of H. ergaster instead of the confusing "heidelbergensis". We can talk of H. ergaster pre-neanderthalensis in much of Europe, H. ergaster pre-sapiens in parts of Africa and H. ergaster without label in all other cases. It's a very legitimate approach and one that really seems supported by the factual evidence. Also, using H. ergaster instead of H. erectus we get rid of the confusing East Asian branch and the earliest less developed African remains as well, simplifying the discussion frame to H. ergaster and its varieties.

    But I won't accept "heidelbergensis" because it normally refers only to a handful of European pre-Neanderthal remains, whatever that narcissistic Stringer says. There is absolutely no evidence than anything that cannot be classified as H. ergaster with Acheulean technology ever migrated between Africa and West Eurasia or vice versa between the earlier H. erectus/habilis and the later H. sapiens flows.


    This actually has been addressed in the literature profusely, over the past several decades. Clearly, part of it is semantics: you call it ergaster, I call it heidelbergensis. The next step is whether heidelbergensis deserves to be a distinct clade across the continents, and across many hundreds of thousands of year. The overwhelming answer is: yes, definitely. This comes from distinct studies of the morphology of the Mauer mandible, other skull features, brain volume, and associated cultural advances (advanced tools, tents and huts, tiled floors, properly weighted spears thicker at the front part and aligned with wood grain, first evidence of hafted composite spears, etc.).

    If you look beyond what you perceive as prejudice in Stringer's review article and look at the original literature cited, you surely cannot deny this.

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    1. "Clearly, part of it is semantics: you call it ergaster, I call it heidelbergensis".

      No. Really H. ergaster has at least a well defined cultural and chronological time-frame and well established and continuously consolidated patterns of expansion into Eurasia (West and South), including Europe and specifically Iberia, where the transition towards Neanderthal forms may have been initiated (??)

      H. heidelbergensis has nothing of that and trying to expand this concept to Africa (without further evidence) is blatantly equivocal and an insult to intelligence.

      "This comes from distinct studies of the morphology of the Mauer mandible"...

      In the paper you sent me Stringer admits that the Mauer mandible is confusing and that most researchers prefer to discard it, notably as most remains are jawless and most comparisons are based on skulls, not jaws.

      "... brain volume"...

      While it's a common point that brain volume is generally relevant to human evolution it is also a well known fact (for those who dare to know) that it varies quite a bit within normal modern humans and prehistorical Neanderthals. For example, Wikipedia mentions 1200-1900 variation in Neanderthals and 1000-1900 variation in modern humans. It may need a bit of cut at the edges but it clearly indicates how much can vary this trait within closely related individuals of the same species, almost 100% and certainly more than 50% rel. to the smaller skull.

      The differences in crania capacity between H. ergaster (i.e. H. heidelbergensis and H. rhodesiensis, among others) and early H. erectus is fully within those ranges, quite smaller in fact.

      "... and associated cultural advances (advanced tools, tents and huts, tiled floors, properly weighted spears thicker at the front part and aligned with wood grain, first evidence of hafted composite spears, etc.)".

      Wait, wait, wait... this is dumping a lot of diverse stuff, most of which is surely questionable (although in general seems to correlate with the gradual increase of brain size in "H. erectus senso lato" before the 'big jump' of 200 Ka ago). What part of this stuff corresponds to European H. heidelbergensis?

      It's thimblerig what you're doing here: moving around the ball faster than my eye can follow. But of course the ball is not and never was under any of the cups, right?




      Delete
  15. "for some reason Europe/ the Levant always gets the "latest and greatest new model" - starting from the Georgian erectus, to antecessor, heidelbergensis, and then Levantine early AMHs. To me this indicates that these crossroads may have been, at least at times, instrumental in carrying genetic innovations bidirectionally, and the NE of Africa"

    The Levant would be the region where any hybrid populations between African and Asian populations would be most likely to occur. I am convinced that 'evolution' involves the interplay between inbreeding and hybrid vigour. Inbreeding leads to fixation of particular genes, which then spread through the appearance of hybrid vigour through the wider population.

    "We can talk of H. ergaster pre-neanderthalensis in much of Europe, H. ergaster pre-sapiens in parts of Africa and H. ergaster without label in all other cases".

    I can agree with that. In fact I suggested much the same in my essay here:

    http://humanevolutionontrial.blogspot.co.nz/2009/06/human-evolution-on-trial-species-or-not.html

    I wrote, 'Homo heidelbergensis is a name for a kind of “Archaic Homo sapiens” but it is doubtful if it should be considered on the one hand to be a single species or on the other a separate species from either Homo erectus or Homo sapiens'.

    "there is reasonable correlation with ice core data - in particular, even with the less well-suited Antarctic data, that albeit have the advantage of going further back".

    I agree. As in geology, 'the present is the key to the past'. 'Present' in this case being the last 150,000 years.

    "Clearly, part of it is semantics: you call it ergaster, I call it heidelbergensis".

    It's all semantics, but that is one of Maju's specialities.

    "If you look beyond what you perceive as prejudice in Stringer's review article and look at the original literature cited, you surely cannot deny this".

    Another of Maju's specialities. If you disagree with the main thrust of a paper discredit the whole thing by claiming 'molecular-clockology', or some such irrelevant claim.

    "While it's a common point that brain volume is generally relevant to human evolution"

    Again I largely agree. Most scientists are intellectuals who value intelligence, and intelligence is often (falsely) correlated with brain size. However we can definitely see an overall, and basically gradual, increase in brain size from Australopithecus to modern humans. So brain size is not completely irrelevant.

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    1. Heidelbergensis is NOT the same thing as ergaster and it's not semantics. All heidelbergensis are ergaster by derivation but they are a particular subset in Europe believed to be precursors of H. nenaderthalensis. Hence they'd be similar to my suggested category H. ergaster pre-neanderthalensis.

      You guys just like muddying the waters but you need a much larger paddle for that, really: one that shows that the African and the European homo effectively interacted in some meaningful way, preferably that there was a migration from either region to the other.

      Nothing of that is anywhere. And until I see that evidence I will keep considering the African and the European branch distinct since c. 900-1300 Ka ago.

      All the rest is ranting and that is YOUR speciality Terry.

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