Tuesday, December 31, 2013

Map of the World with Approximate LGM Sea Level

 
NOAA National Geophysical Data Center map of the world with sea level 110 meters lower than today.
 
Link to the zoomable version.
 
The sea level during the Last Glacial Maximum(LGM) has been estimated to have reached as low as -120 meters.  See Refining the eustatic sea-level curve since the Last Glacial Maximum using far and intermediate field sites, Fleming et al.

25 comments:

  1. Some interesting aspects to the map. I'm sure large regions shown as dry land were far from being so. I notice it has Australia and New Guinea completely connected whereas it seems quite obvious that the land connection was minimal. The two regions share very few haplogroups and those they do fit more a sea connection rather than a land one.

    It has also become obvious to me that the Sundaland region was certainly not completely dry land. The route southeast looks to have been what is now the malay Peninsula and the GReater Sunda Islands. Borneo and the Philiipines have always been a bit isolated from that main region.

    Similarly the North China Plain and its extension may also have been largely uninhabitable for most of human history. That would mean that northward-moving populations would be forced to use a route through the higher country between Tibet and China. To me that appears to provide the closest fit with the expansion of haplogroups in East Asia.

    Concerning your more recent entry about rise and fall of sea level. I note that there are two possibilities for the movement from Timor to Australia: the earliest around 60 kya. with a more recent option at something like 48 kya. I wonder which is the correct period for the crossing.

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  2. There are a number of recent papers that refine the sea level in South East Asia. I'm sure this map is only approximate and only valid for the -110 meter level.

    I'm not sure why you say that the North China plain was uninhabitable.

    Regarding "populations would be forced to use route through the higher country between Tibet and China", maybe.

    There is the obvious north-south route between the Altai, through western Afghanistan and Pakistan. I wrote a post about that a few years back:

    https://www.google.com/#q=westward+across+the+steppe

    There is also an ever accumulating amount of evidence for a route between Europe, Mezmaiskaya, what is today Kyrgyzstan, the Altai, Lake Baikal and Beringia. (And probably also joining to Sakhalin and Japan.)

    To me, the most obvious inaccuracy of the map is the missing Caspian Sea. For that, see the side bar "Europe During the Last Glacial Maximum".

    " the earliest around 60 kya. with a more recent option at something like 48 kya. I wonder which is the correct period for the crossing. "

    Probably both.

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  3. Terry, another thing I would mention is that many discussions, The Genographic Project (National Geographic) and even some scientific papers continues to discuss human migrations in very simplistic terms, (ie, hunter Joe put his back pack on and walked or paddled, one way, from Africa to Beringia.) Given the recent evidence of the last several years, I think it is about time that we started to talk about bidirectional and multidirectional population movements driver by climate. This has been going on for a lot longer than the Genographic Program standard blurb.

    (Sorry Spencer!)

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  4. "it is about time that we started to talk about bidirectional and multidirectional population movements"

    I very much agree with that statement. I think people are too ready to see ancient population expansions as somehow 'biblical'.

    "There is also an ever accumulating amount of evidence for a route between Europe, Mezmaiskaya, what is today Kyrgyzstan, the Altai, Lake Baikal and Beringia".

    I have long accepted that Y-DNA C and mt-DNA N moved east, not through South Asia but via some more northerly route, and so it is interesting to read that comment.

    "I'm not sure why you say that the North China plain was uninhabitable".

    To me it seems that the plain was first closely settled during Y-DNA O's expansion. In other words during the Neolithic. It also seems likely that, until population pressure built, humans were most comfortable living in semi-open woodland rather than in deep forest. The regions shown in the map as 'dry land' were almost certainly not exactly that. The low-lying region between Australia and New Guinea would have been similar to what the southern region of Papua New Guinea is like today: a tangled mass of mangrove swamp and jungle. I suspect something similar for much of Sunda although it is less likely for the Yellow Sea.

    "Probably both".

    Perhaps. I certainly see evidence for two separate migrations into Sahul. The earliest reached just Australia (Y-DNA C and mt-DNA N) but as boating improved people were able to travel along the coast and then across open water to New Guinea (Y-DNA K and mt-DNA M).

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  5. There's this recent paper on the Paleolithic in China:

    Paleolithic Archaeology in China
    Annual Review of Anthropology
    Vol. 41: 319-335 (Volume publication date October 2012)
    First published online as a Review in Advance on July 2, 2012
    DOI: 10.1146/annurev-anthro-092611-145832
    Authors: Ofer Bar-Yosef and Youping Wang

    Abstract:

    Despite almost a century of research, the Chinese Paleolithic chronocultural sequence still remains incomplete, although the number of well-dated sites is rapidly increasing. The Chinese Paleolithic is marked by the long persistence of core-and-flake and cobble-tool industries, so interpretation of cultural and social behavior of humans in East Asia based solely on comparison with the African and western Eurasian prehistoric sequences becomes problematic, such as in assessing cognitive evolutionary stages. For the Chinese Paleolithic, wood and bamboo likely served as raw materials for the production of daily objects since the arrival of the earliest migrants from western Asia, although poor preservation is a problem. Contrary to the notion of a “Movius Line” with handaxes not present on the China side, China does have a limited distribution of Acheulian bifaces and unifaces. Similarly, Middle Paleolithic assemblages are present in the Chinese sequence. Although the available raw materials have been assumed to have limited applicable knapping techniques in China, this notion is challenged by the appearance of microblade industries in the north in the Upper Paleolithic. In the south, early pottery making by foragers emerged 20,000 years ago, thus preceding the emergence of farming but heralding the long tradition of cooking in China.

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  6. And this 2013 paper:

    The Chinese Upper Paleolithic: Geography, Chronology, and Techno-typology

    http://link.springer.com/article/10.1007/s10814-012-9059-4#page-1

    It states that the Chinese Upper Palaeolithic started at about 35,000 years ago.

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  7. " humans were most comfortable living in semi-open woodland rather than in deep forest"

    Well, it looks like most humans were either fishing, catching birds, or following aurochs, bison, horses, reindeer, deer, gazelles, elephants and sometimes mammoths. Some of these animals live in forests (deer), but most live on open or lightly forested areas. Fishing is another story. Many salmon rivers run through deeply forested areas.

    In West Africa, some people were known to live in forests by emphasizing forest tubers (vegetables) in their diets.

    There were probably some forest specialists, but I agree that the preference appears to have been open or lightly forested land.

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  8. "The Chinese Paleolithic is marked by the long persistence of core-and-flake and cobble-tool industries"

    That has been widely accepted for a long time. In fact much the same holds for all of East Asia including SE Asia and Australia. To me it has always been the main argument against 'modern humans' as being marked by Upper Paleolithic. In spite of the abstract's disclaimer as to the Movius line the above does indicate a very abrupt faultline between South and East Asia, indicating a fairly effective barrier to free movement between the two regions. The presence of this barrier is further born out 'the appearance of microblade industries in the north in the Upper Paleolithic'. In other words it didn't arrive via South Asia.

    "the Chinese Upper Palaeolithic started at about 35,000 years ago".

    That too has been long-accepted.

    "Some of these animals live in forests (deer), but most live on open or lightly forested areas. Fishing is another story. Many salmon rivers run through deeply forested areas".

    Many stretches of salmon rivers are not through heavily forested regions though.

    "In West Africa, some people were known to live in forests by emphasizing forest tubers (vegetables) in their diets. There were probably some forest specialists"

    From haplogroup diversity it looks to me as though the Pygmies do not have a particulary ancient presence in the deep forest. They may have been pushed there by the same population pressure that gave rise to the OoA.

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  9. "That has been widely accepted for a long time. In fact much the same holds for all of East Asia including SE Asia and Australia. To me it has always been the main argument against 'modern humans' as being marked by Upper Paleolithic. In spite of the abstract's disclaimer as to the Movius line the above does indicate a very abrupt faultline between South and East Asia, indicating a fairly effective barrier to free movement between the two regions. The presence of this barrier is further born out 'the appearance of microblade industries in the north in the Upper Paleolithic'. In other words it didn't arrive via South Asia. "

    I'm not even a very good novice on this topic, and haven't yet had a chance to read up on the Palaeolithic in China, but I have to say that I would be inclined to weigh with careful consideration any research by Ofer Bar-Yosef.

    http://en.wikipedia.org/wiki/Ofer_Bar-Yosef

    "The presence of this barrier is further born out 'the appearance of microblade industries in the north in the Upper Paleolithic'."

    You might find interesting a paper I recently have been combing through on lithic development in Japan:

    Title: The evolution of lithic technology and human behavior from MIS 3 to MIS 2 in the Japanese Upper Paleolithic

    Author: Kazuki Morisaki

    Journal: Quaternary International


    "Many stretches of salmon rivers are not through heavily forested regions though."

    Some are, some aren't.


    "From haplogroup diversity it looks to me as though the Pygmies do not have a particulary ancient presence in the deep forest."

    Here, I was specifically thinking of people of various people of West Africa, not central Africa.

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  10. "You might find interesting a paper I recently have been combing through on lithic development in Japan"

    I could only access the abstract of the Morisaki paper but I see:

    "The EUP/LUP transition, at ca. 25,000 14C BP"

    Obviously the EUP developed in Japan before that time which fits its arrival in China at '35,000–30,000 years ago' from the Bar-Yosef paper. As he says:

    "The proliferation of blade assemblages in northwest China is interpreted as the cultural impact or the physical presence of bearers of blade industries from western Eurasia".

    Nothing via South Asia.

    "Here, I was specifically thinking of people of various people of West Africa, not central Africa".

    But the Pygmies are the only hunter-gatherers who inhabit the deep forest. The other people in the jungle are mainly farming people who have preseumably invaded the forest reasonably recently. The Pygmies probably evolved in the forested regions.

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  11. Terry, I just sent you the pdf for the Morisaki paper.

    Regarding forest specialists in West Africa, I was referring in my commnent to the Kintempo complex. The Kintempo complex includes grassland and forest specialists, as well as coast dwellers.

    I lived there as a kid and can definitely attest to the fact that parts of West Africa are covered in dense forest.

    Here's an example of what it looks like:

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

    I think that people in Cameroun, Congo and other parts of Central Africa also live in the forest.

    For a good general reference, See "The Archaeology of Africa: Food, Metal and Towns".

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  12. Thanks for the paper (I haven't had a chance to look at it yet) and thanks for the link to the park. Where did you live? Ghana? I visited the Gambia, Senegal and Mali early in the 80s. Sahel region of course.

    "I think that people in Cameroun, Congo and other parts of Central Africa also live in the forest".

    But did they live in the forest as hunter-gatherers or is it only since cultivation was adopted? As I understand things the population of the coastal regions grew with the European involvement in the slave trade, necessarily along the coast. Most of the early civilizations were certainly more inland. I see the Kintempo was certainly post agriculture, although I'm sure the most productive human habitat has always been on the margin between forst and grassland.

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  13. I lived in Takoradi-Sekondi in Ghana.

    "But did they live in the forest as hunter-gatherers or is it only since cultivation was adopted?"

    This is a very detailed topic which I can't answer properly here.

    A good reference would be:

    The Oxford Handbook of African Archaeology
    edited by Peter Mitchell, Paul Lane
    2013

    By the way, I previously said Kintempo Complex. It is Kintampo Complex.

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  14. "It is Kintampo Complex"

    I see on a ecological map I have that Kintampo district is described as 'tropical grassland and Savanna, with tall grass and scattered low trees and bushes (baobab, acacia)'. So it's not in the dense forest region of Ghana, whereas Takoradi-Sekondi is on the coast, very near the 'Tropical Rain Forest' region.

    I don't know if you've seen Maju's mt-DNA L diagrams:

    http://leherensuge.blogspot.co.nz/2010/03/reviewing-mtdna-l-lineages-notes-l0.html

    For L0 and the other accessible from the bottom of the page. From other sources We know that Western Pygmies are primarily L1c1a and eastern Pygmies are L0a2b, L2a2 and L5a1c. All these haplogroups are shared with nearby non-Pygmy populations, indicating the jungle-dwelling pygmies are by no means an 'ancient' population. I'll try to find The Oxford Handbook of African Archaeology.

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  15. I see you're arguing with Maju. That you are some way off proving he is wrong is demonstrated by the fact he hasn't threatened to ban you yet. You'll know you've reached the stage where he has to admit he's wrong because he will actually ban you. That has been the usual pattern.

    It seems from the Morisaki paper that Japan was uninhabited until the Early Upper Paleolithic arrived, very soon after it first appeared in North China. That in itself is interesting. Ancient humans may have been unable to move far enough north to move through the Korean Peninsula to Japan. It seems likely Y-DNAs Q and R introduced the UP to China from further west but both seem virtually unknown in Japan. The earliest Y-DNAs there appear to be C1 and D2. Presumably these haplogroups picked up the UP from Q and R and carried it to Japan. Interestingly Japanese C1 is now thought to be close to the newly identified European C6. These haplogroups are in turn possibly related to South Asian C5. D2's relations are spread in an arc from the Andaman Islands, through Tibet and into Mongolia. Seems there was a lot of movement during the Eurasian Upper Paleolithic.

    Turning to SE Asia. It seems likely that at times of lowered sea level, and increased cold and aridity, the higher ground through the region may have been less heavily forested than was the lower land. More accessible to humans. We certainly have basal mt-DNA Ms scattered along the peninsula (less so with N, except for R-derived haplogroups). But surprisingly it seems there are no basal haplogroups indigenous to Borneo even though ancient human remains have been found in Palwan, and even further into the Philippines proper. Perhaps Borneo was so inhostitable that people left as soon as the opportunity arose. Y-DNAs S and M must have come from somewhere in Sunda, as must have the Sahul mt-DNA M-derived haplogroups. Of further interest is the mt-DNAs M24'41 and M19'53. One branch of each in Palawan, the other in South Asia. Perhaps the connection here is from east to west rather than the usually assumed west to east. Adding to the confusion (or not?) is the M42'74 haplogroup: M74 in southern China with M42 in both South Asia and Australia.

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  16. "It seems from the Morisaki paper that Japan was uninhabited until the Early Upper Paleolithic arrived" . . .

    There is some evidence from several other papers that Japan may have been inhabited earlier. But the arrival of Upper Palaeolithic Hunter Gatherers in Japan seems to have occurred between 40 and 30 thousand years ago. Japan could have been occupied from the Sakhalin Islands, as well.

    "Ancient humans may have been unable to move far enough north to move through the Korean Peninsula to Japan."

    I don't get this, Terry. I don't think there is yet evidence yeah or neah to support this. There is a the moment quite a bit of archaeology being done in Beringia. I guess at some point they'll be able to date the earliest Upper Palaeolithic in Beringia.

    Regarding looking at y-dna haplogroups, it's interesting. However, often I find it very confusing. So I usually look at the autosomal data and the archaeological record. Sometime, I check back with mtDNA.

    I don't know enough about the fine details over time of these y-dna distributions to comment.

    I do follow your discussions of SE Asia with interest. Your observations about the arrival of mt-DNA N in SE Asia caught my eye.

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  17. "There is some evidence from several other papers that Japan may have been inhabited earlier".

    Not very reliable as I understand things.

    "But the arrival of Upper Palaeolithic Hunter Gatherers in Japan seems to have occurred between 40 and 30 thousand years ago".

    Which fits very closely with your above comment, 'the Chinese Upper Palaeolithic started at about 35,000 years ago'.

    "I don't get this, Terry. I don't think there is yet evidence yeah or neah to support this. There is a the moment quite a bit of archaeology being done in Beringia. I guess at some point they'll be able to date the earliest Upper Palaeolithic in Beringia".

    The presence in Beringia is unlikely to be earlier than 30,000 years ago is my best guess. In other words it is associated with the Upper Paleolithic expansion the Malt'a boy was a member of. The fact he has virtually no East Asian element suggests his population had not met the East Asian EDAR370A carrying population at 27,000 years ago (as I remember his dating). The paper on the EDAR mutation shows its origin as being in the high country of northwest China at not quite 40 degrees N, which makes complete sense. To reach Japan via the Korean Peninsula involves a movement north of 40 degrees which may not have been possible until the UP.

    "Japan could have been occupied from the Sakhalin Islands, as well".

    And probably was. But that is even further north.

    "Regarding looking at y-dna haplogroups, it's interesting. However, often I find it very confusing. So I usually look at the autosomal data and the archaeological record. Sometime, I check back with mtDNA."

    Have you seen the McDonald maps of some years ago? Later research has not really affected the distribution he shows very much:

    http://s155239215.onlinehome.us/turkic/60_Genetics/JDMcDonaldDNAmapsEn.htm

    "Your observations about the arrival of mt-DNA N in SE Asia caught my eye"

    Have you seen the list of mt-DNA haplogroups Maju let me post some time ago? I arranged them from west to east in the case of M and N, and from east to west in the case of R. Maju agreed totally with my distribution details but still disagrees with my conclusions:

    http://ourorigins.wikia.com/wiki/Human_Prehistory_and_Genetics_Wiki

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    1. I had a look at both of these links. It's hard to tell what you are getting at.

      Maybe you could fill me in.

      Delete
  18. Terry, thanks for these comments and suggestions. It's late now, but I'll have a look at the maps you are suggesting.

    The Mal'ta boy did have some Oceanian ancestry, so that does make me wonder. Also, someone commented that there was genotyping error due to the age of this sample. That does make me a little ambivalent about this sample.

    I think they are just beginning to explore the peopling of Beringia, so I don't have any clear thoughts on this topic as of yet.

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  19. "someone commented that there was genotyping error due to the age of this sample".

    In my experience such comments most usually come from someone who doesn't like the findings. The find makes their previously-held belief untenable. I'm prepared to take the research at face value, at least for now.

    "The Mal'ta boy did have some Oceanian ancestry, so that does make me wonder".

    To me it is almost certain that both Y-DNA MNOPS and mt-DNA R originated in Sundaland, near (or even in) Wallacea. If that is so then it would follow that the expansion would carry at least some element of the Oceanian substrate.

    "I think they are just beginning to explore the peopling of Beringia, so I don't have any clear thoughts on this topic as of yet".

    I haven't really considered Beringia very much at all yet. My interest was originally primarily in Polynesian origins. However I have found that the results from that can be considerably extrapolated as it includes Australia, New Guinea, Melanesia, island and mainland SE Asia, along with Neolithic China.

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    1. The observation of "genotyping error" was made in a twitter post of Joe Pickrell (author of Treemix). I think he was just pointing out that there was some error in the MA1 sequencing. He wasn't discounting the overall conclusion of the paper.
      .
      Very interesting observation about Y-DNA MNOPS and mt-DNA R. I'll have to think a little more about it.

      Delete
  20. "Maybe you could fill me in".

    I mean considering both the distribution and the phylogeny should give an idea of where each haplogroup branch originated. I assumed M and N had originated close to Africa and so I sorted them from west to east. I noticed that M does have haplogroups through SE Asia, including Sumatra (M47 and M26). These haplogroups lie between the more northerly M haplogroups and the Australian M42, M14 and M15, and New Guinea/Melanesian M27, M28 and M29'Q. N on the other hand has a huge gap between Thai/Laos N21 and N22 and the Australian N13, N14, O and S. That seemed very strange until I considered that R might have originated in the gap. R actually fills the gap completely: P in Australia, R12'21 in the Malay Negritos and in Australia, R14 in the Lesser Sunda Islands, R22 in the Lesser Sunda Islands but also in Malaysia and R23 straddling Wallace's Line in Bali and Sunda. To me that confirmed that R had originated in the region, probably in the Lesser Sunda Islands.

    I have actually made some primitive maps of the 3 haplogroups' SE Asian distribution. If you like I could scan them and send you a copy.

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  21. Terry, I don't really know very much about mtDNA distributions. They mostly seem to be very widely distributed and unless they can be verified with ancient DNA, I'm ambivalent about using them to pinpoint "origin".

    In talking with Luis, I know he relies heavily on mtDNA. We had a long discussion at one point about the origin of the L-L1 split:

    http://linearpopulationmodel.blogspot.com/2012/11/for-what-they-were-we-are-on-h1-in.html

    In general, Luis had some very insightful comments regarding the very long sequence between mtDNA L1-U. However, I think it would be very difficult without ancient DNA to better understand these dispersals.

    That being said, I would be happy to look at your maps. I confess that it might take me several weeks to look at them. I don't have a good grasp on South East Asian geography. (Also, I'm not really up on the existing various theories regarding the origin of mtDNA N and M.)

    Terry, have you ever thought of starting your own blog?

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  22. "Terry, have you ever thought of starting your own blog?"

    Not really because it seems to involve a large amount of time.

    "They mostly seem to be very widely distributed and unless they can be verified with ancient DNA, I'm ambivalent about using them to pinpoint 'origin'".

    I think we can reasonably safely assume that individual haplogroups originated somewhere within their present distribution. If a large number of basal branches are concentrated in a small region we can then be confident that is where the haplogroup first originated.

    "In talking with Luis, I know he relies heavily on mtDNA".

    And I agree with him on that. However I disagree with his comment in your earlier discussion with him:

    "In my understanding all three super-haplogroups coalesced in Southern Asia without doubt".

    He has always looked for a single region of origin for 'modern humans' and his desire to place the three main mt-DNAs in a single region stems from this desire. I see no reason why they should not have originated in three separate regions. Also from Maju:

    "The L3 node was in Africa, no doubt, but the M, N and R nodes must be located in Southern Asia (senso lato), possibly in the Indian subcontinent but could also be in some cases SE Asia or (some claim, without any solid support IMO) in West Asia".

    He is refering to my claim my conclusions regarding R with ' but could also be in some cases SE Asia. And I disagree with 'or (some claim, without any solid support IMO) in West Asia' for N. He tends to claim a South Asian origin for N but his comments concerning M, N and R in Africa (But from an empirical viewpoint there is no doubt: the basal diversity of M, N and R in Africa is ridiculously low) apply to N in South Asia: no basal N haplogroups there. I also disagree with his ideas concerning long mutation tails:

    "This extra time is precisely what is needed to more easily allow for a long migration as small groups through non-hospitable lands, like the OoA through an arid and maybe already settled Arabia".

    Human groups would migrate when conditions a favourable, not harsh. As a result haplogroups would diversify while expanding in good environmentla conditions and would remain static and isolated during harsh ecological conditions, thus developing a long mutation tail.

    I haven't scanned the maps yet and it could be some time before I do. That should suit us both.

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    1. It would be great if you could start a blog and post your maps and other data. If you are concerned about time, just turn off comments.

      I could link your blog in so others could easily find it.

      It would be a good way for you to convey a visual picture of your idea.

      Delete

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