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Aiko
Thursday, November 4th, 2004, 10:29 PM
The East Asian material is the material most often ignored by proponents of the Out of Africa model, and the one most touted by the Multiregional proponents as evidence to support their theory. The Japanese and Indonesian sequence is filled with problems associated with dating and provenience, that make any argument connecting the various material specious.

The Ngandong material are a clear example of this. The material is conventionally listed as H. erectus by most researchers, but has been redated to 53 kyr to 27 kyr, and may be a link to modern East Asians. I am a bit skeptical of this for now, but as the possibility is fascinating and cannot be ignored (not to mention the material is more important to discuss as a link from archaic East Asians to modern East Asians rather than a late surviving archaic of a population that left no modern progeny). The Ngandong material provides the single largest collection of crania from Java, with 15 specimens (including two tibiae) recovered from the High Terrace of the Solo River near Ngandong, and an additional female was discovered at nearby Ngawi.
This material (often called Solo rather than Ngandong) was originally placed in the Late Pleistocene due to the associated fauna found. Several attempts at dating have given dates of 101 kyr ± 10 kyr (uranium/thorium dating of animal bones), 165 kyr (dating of a nearby High Terrace site), less than 250 kyr (date from fission track dating from similar Javan deposits), older than 300 kyr (modified ESR date from one of the crania), and approximately 500 kyr (Potassium/Argon date from a tuff near the site). However, these date have come into question based on dates presented by C. Swisher et al. of 53 kyr to 27 kyr based on U-series and ESR dating of animal teeth from other deposits found near the site.

The Ngandong material were studied intensively by F. Weidenreich, but he died during the preparation of a monograph on the material, and it was published incomplete. Of the 13 crania or cranial fragments, nine are clearly adult, and one is clearly a juvenile (the rest are not diagnostic). It is believed that Solo 5, 9, 10, and 11 are male, and Solo 1, 4, 6, 8, and the Ngawi specimen are female. The juvenile (Solo 2) is likely male. The determination of sex is based on cranial size, projection and size of the nuchal torus, and the development oa an external occipital protuberance. These features do not overlap between the sexes. Other characteristics do overlap, but show a average difference between the sexes, including vault thickness and development of the lines and crests marking the muscle attachments.
These specimens are purported to share a number of similarities (regional similarities if the MRE hypothesis holds in East Asia) with earlier Indonesian specimens like the Sangiran material and the Sambungmachan material. Similarities that are reported between these samples include:


The frontal bone is flat, without any development of a frontal boss, and merges onto the top of the supraorbital torus.
The supraorbital torus is close to horizontal in orientation.
There is a distinct frontal keel extending over virtually the entire squama.
There is a prebregmatic eminence, a cross-like elevation at the meeting of the sagittal and coronal sutures.
The top of the vault is evenly curved along the sagittal suture.
While there are isolated teeth that seem to be associalted with the later Middle and early Upper Pleistocene faunas known from several East Asian countries, the vast majority of material from this time period comes from China. The material from China comes from a broad spatial span, and includes several nearly complete crania, as well as much of a postcranial skeleton. This is the region where multiregional hypotheses gain their best evidence (indeed, some researchers have begun to accept continuity in East Asia, while maintaining support for replacement in Europe). The earliest material from China that has been designated as H. sapiens (or at least has a good probability of being H. sapiens) is the Dali cranium from Shaanxi Province, and several teeth from Tongzi in Guizhou Province.

The Dali cranium was found in river gravels, and sustained some damage on its lower face that has never been reconstructed. This damage pushed the maxilla upwards, making the lower face look shorter than it actually was. The cranium came from a male individual under 30 years of age. Some of the features include:


A large, thick cranial vault.
A small braincase (1120 cc).
Large supraorbital tori that arch over the upper orbits.
A low forehead that begins behind the ridges.
A distinct frontal boss.
Presence of a narrow sagittal keel.
The occipital squama is expanded relative to the size of the nuchal plane.
The parietal bosses are well-developed.

The Dali cranium has several other features that have been presented as evidence of a link between the earlier Chinese material from Zhoukoudian, as well as between the Java material from Ngandong. These features are also used as evidence to fit Dali into a set of "East Asia" characteristics that link the fossil material between what is generally considered the East Asian H. erectus material and modern living Asians. These characteristics include:


The angular torus.
The temporal-frontal articulation in the temple region.
The thick vault bones.
The depressed region where the browridges meet over the nose.
An elevated lower cheek border.
The presence of a maxillary notch.
Orbital pillars that face forward.
Nasal bones that are narrow, flat, and oriented vertically, with a constricted internasal crest.
A moderate swelling of the maxilla along the nasal border.

While the lack of dentition in Dali prevents the inquiry into whether it had shovel-shaped incisors like current East Asian populations, the six teeth from Tongzi include a central incisor that is shovel-shaped in the normal East Asian pattern. The incisor has moderately strong marginal ridges, a lingual tubercle, and a straight buccal face. This is another point in favor of East Asian continuity.

From a little more recent time period in China, comes the Jinniushan material. The material from Jinniushan in Liaoning Province consists of the cranium and much of the postcranial skeleton of a 20-year-old female. The postcrania include four vertebrae, some ribs, an os coxa, an ulna, a patella, and 30 hand and foot bones. The remains were found in a consolidated fissure-filling in an isolated karst prominence. ESR dates (early uptake model) by Chen Tiemei et al. has given a dat of approximately 187 kyr (165 kyr to 195 kyr) for this material. The cranium has the following features:


A large cranial vault (1260 cc).
Unusually thin vault bones.
A gabled cranial contour.
A broad frontal bone.
Central supraorbital thinning.
A gracilized posterior region with marked nuchal plane reduction.

While these features combine to make Jinniushan the earliest specimen with this mixture of modern features, there are many features that are not modern. These features include a great distance between the orbits, the supraorbitals project far in front of the forehead, and the nuchal torus extends across the entire occipital bone and has a distinct, straight upper border there. However, the case for calling this specimen modern H. sapiens is probably as strong as African (Klasies River Mouth) and West Asian (Qafzeh) samples of almost half the age of Jinniushan. This specimen has also been used as a link to the earlier Zhoukoudian material, with similar features that include:


Arched supraorbitals with a sulcus separating them from the frontal squama.
A tall narrow keel on the frontal bone.
Transversely flat, vertically oriented face.
Marked facial breadth.
The top of the nasal bones makes a horizontal juncture with the frontal bone.
A high position for the maxillary notch.
Incisor shoveling, marginal ridges combined with a straight incisor blade with a tubercle with finger-like projections extending above it.
M3 reduction.

Other earlier H. sapiens remains from China include a maxilla and occipital bone from Chaohu (also known as both Chaoxian and Yinshan) in Anhui Province, the Changyang maxilla from Hubei, a child's parietal and teeth from Dincun (Shanxi), teeth from Xindong (Beijing), a skullcap from Maba in Guangdong Province, and material from ten individuals at Xujiayao (Shanxi) (2, 3, mandible).

The unequivocable modern H. sapiens from continental East Asia include: the Liujiang material (67 kyr), cranial and limb remains from Salawusu (50 kyr to 37 kyr), the Laishui material (60 kyr), the Ziyang material (either 39 kyr to 36 kyr, or 7 kyr depending on which level it came from, though this can no longer be established), the Upper Cave (101, 102) material at Zhoukoudian (29 kyr to 24 kyr), an occipital from Shiyu (28 kyr), the Hamakita material from Japan, the Yamashita-cho material from Okinawa (32 kyr), the Pinza-Abu cranial fragment and postcrania (26 kyr), the Minatogawa material (18 kyr), the Niah Cave material from Borneo (40 kyr), and the Wadjak material (1, 2) from Indonesia.

nordic_canadian_male
Thursday, November 4th, 2004, 11:11 PM
Material from both asia, europe, and the middle east all show proof of racial continuity. These archaic skeletons all show asian or caucasian features, although they may be more robust and not yet modern, they are the ancestors of modern out of africa populations. The mechanism of gracilazation simply took over as our soceity became more complex, smaller faces, teeth, bones, all came with the progress toward civilization. The Mitrochondrial clock geneticist speak of is correct, showing that yes we all share a common ancestor but not in the last 150 thousand years but within the last half million years. Homo Erectus is that common ancestor, he gave rise to modern populations.

Aiko
Saturday, November 13th, 2004, 12:26 AM
Asian and European physical characteristics have antiquity in their regions going back over 100,000 years. Many Europeans have relatively heavy brow ridges reminiscent of Neanderthals. Similarly, Chinese facial characteristics can be seen in Asian archaic Homo sapiens dating to 200,000 years ago. Like local Homo erectus, Sinids today shovel-shaped incisors while Africans and Europeans rarely do. This supports the contention of direct genetic links between Asian Homo erectus and Nothern Asians. Australian aborigines share key skeletal and dental traits with people who inhabited Indonesia at least 100,000 years ago. The implication is that there was no complete replacement by modern humans from Africa 50,000 years ago. Frayer gives good arguments that a number of European fossils from the last 50,000 years have characteristics that are the result of archaic and modern Homo sapiens interbreeding.

Also, Bräuer proposes that the first modern humans did evolve in Africa, but when they migrated into other regions they did not simply replace existing human populations. Rather, they interbred to a limited degree with late archaic Homo sapiens resulting in hybrid populations. In Europe, for instance, the first modern humans appear in the archaeological record rather suddenly sometime after 40,000 years ago. The abruptness of the appearance of these Cro-Magnon people could be explained by their migrating into the region from another area, possibly Southwest Asia or North Africa. They apparently shared Europe with Neandertals for another 10,000 years or more. During this long time period, it is argued that interbreeding occurred and that the partially hybridized predominantly Cro-Magnon population ultimately became the modern Europeans. The Pestera cu Oase discovery supports this hypothesis. It is a skeleton of a 15-16 year old male Homo sapiens who lived about 35,000 years ago. He has a mix of old and new anatomical features. The skull has characteristics of both modern and archaic Homo sapiens. Trinkaus believes that could be the result of interbreeding with Neanderthals.

Part of the mitochondrial DNA was extracted recently from the bones of a 60,000 year old modern Homo sapiens skeleton found in 1974 on the shores of Lake Mungo in Southeastern Australia. This is the oldest DNA that has been extracted from a human so far. Comparison of this DNA with that of nine other ancient Australian skeletons, 2 Neandertals, and 3,453 contemporary people from around the world indicates that "Mungo Man" had a unique genetic marker. This indicates that a now lost genetic line of modern Homo sapiens existed in Australia prior to the arrival of later Australian Aborigines. This evidence provides significant support for rejecting the "out of Africa" replacement model of modern Homo sapiens evolution.

Alan Templeton reported that a new computer-based analysis of 10 different human DNA sequences indicate that there has been interbreeding between people living in Asia, Europe, and Africa for at least 600,000 years. These data again suggest that the complete replacement model of Homo sapiens origin is incorrect. According to Templeton, "humans expanded again and again out of Africa, but these expansions resulted in interbreeding, not replacement."

Homo sapiens skull from Liujiang County in Southern China has been tentatively dated to 139,000-111,000 years ago and that Homo sapiens sapiens teeth from two other sites in the same area have been dated to 94,000 years ago.

"Out of Africa" replacement model is not conclusive by Asian evidence.

Northern Paladin
Saturday, November 13th, 2004, 03:28 AM
Shoved shaped incisors are not exclusively found in East Asian populations.
Some Northern European groups exhibit this trait as well.

morfrain_encilgar
Saturday, November 13th, 2004, 04:11 AM
Shoved shaped incisors are not exclusively found in East Asian populations.
Some Northern European groups exhibit this trait as well.

Shovel shaped incisors are an archaic trait, the Sinodont form of shovelled incisor is exclusively East Asian (and American) but it isn't found in Asian erectus specimens.

Northern Paladin
Saturday, November 13th, 2004, 07:25 AM
Shovel shaped incisors are an archaic trait, the Sinodont form of shovelled incisor is exclusively East Asian (and American) but it isn't found in Asian erectus specimens.

If they are an archaic trait how come Modern East Asians still have them?

I read that shovel shaped inicisors are rather common in Swedes. Aren't they just a cold adapadation? If not what possible function would you attribute to them?

morfrain_encilgar
Saturday, November 13th, 2004, 11:33 AM
If they are an archaic trait how come Modern East Asians still have them?

I read that shovel shaped inicisors are rather common in Swedes. Aren't they just a cold adapadation? If not what possible function would you attribute to them?

Well archaic means a feature hasn't changed from its ancestral state. In some ways different races are more archaic than each other in certain race, like they have all come further from a shared ancestor in different ways, too. In this case, I said that shovelling is archaic, because it is known among erectus and neanderthaloids. In moderns (especially Sinodonts) the high frequency of shovelling does appear to be related to a cold climate, even though Sinodont dentition is derived from the Sundadont condition.

The frequency of incisor shovelling in northern Europeans (including the Lapps) is actually nowhere near the frequency in north-east Asians, except among Finns from Helsinki.

Scoob
Saturday, November 13th, 2004, 03:59 PM
Khoisan (African Bushmen) also have shovel-shaped incisors.

morfrain_encilgar
Saturday, November 13th, 2004, 04:25 PM
Khoisan (African Bushmen) also have shovel-shaped incisors.

I have heard so, but I don't have any data about the frequency in Bushmen.

Scoob
Saturday, November 13th, 2004, 04:33 PM
At this point, the genetic preponderance of evidence indicates that the Out of Africa model (where humans replaced archaic sapiens in the Old World) is overall correct. Multiregionalism is basically dead in academia, except maybe as a minor footnote to OOA (i.e., some small amount of archaic sapiens DNA has been integrated into modern humans.)

morfrain_encilgar
Saturday, November 13th, 2004, 04:47 PM
At this point, the genetic preponderance of evidence indicates that the Out of Africa model (where humans replaced archaic sapiens in the Old World) is overall correct. Multiregionalism is basically dead in academia, except maybe as a minor footnote to OOA (i.e., some small amount of archaic sapiens DNA has been integrated into modern humans.)

The reality of the origin of moderns in Africa is extremely well supported, however the anatomical evidence for regional continuity is strong and it seems to be growing.

Scoob
Saturday, November 13th, 2004, 05:13 PM
The reality of the origin of moderns in Africa is extremely well supported, however the anatomical evidence for regional continuity is strong and it seems to be growing. Perhaps archaic sapiens contributed very few genes to modern humans, but these genes had a strong effect on phenotype.

What makes this possibility doubtful is that when mixing occurs, it tends to leave its mark throughout a genome, and would thus include many genes that don't apparently influence phenotype.

The other possibility is that somehow there were strong selective forces on the continents that independently reproduced similar phenotypes in both archaic sapiens and modern sapiens.

We need much more genetic data to determine this - especially if there is archaic admixture at a very low level.

morfrain_encilgar
Saturday, November 13th, 2004, 06:48 PM
Perhaps archaic sapiens contributed very few genes to modern humans, but these genes had a strong effect on phenotype.

What makes this possibility doubtful is that when mixing occurs, it tends to leave its mark throughout a genome, and would thus include many genes that don't apparently influence phenotype.

The other possibility is that somehow there were strong selective forces on the continents that independently reproduced similar phenotypes in both archaic sapiens and modern sapiens.

We need much more genetic data to determine this - especially if there is archaic admixture at a very low level.

I don't know about the new research using autosomal markers, but the evidence from studies of parental lineages doesn't show evidence of admixture except in an Upper Paleolithic Australian. However, such lineages become lost over time so don't provide evidence against regional admisture. I think everyone agrees that any regional admixture was limited or moderns wouldnt be so closely related to each other.