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Jean M
05-01-2014, 12:26 AM
Chris Stringer, Why we are not all multiregionalists now, Trends in Ecology & Evolution, Volume 29, Issue 5, p248Ė251, May 2014
http://www.cell.com/trends/ecology-evolution/fulltext/S0169-5347%2814%2900047-0

Stringer fights back! Full paper on open access.

Mandoos
05-01-2014, 01:33 AM
Maybe it's some grudge for the Chinese who certainly don't want to believe in OOA.

Jean M
05-01-2014, 09:10 AM
No, he cites the people/ideas he is fighting.


Recent revelations that human genomes contain DNA introgressed through interbreeding with archaic populations outside of Africa have led to reassessments of models for the origins of our species. The fact that small portions of the DNA of recent Homo sapiens derive from ancient populations in more than one region of the world makes our origins ‘multiregional’, but does that mean that the multiregional model of modern human origins has been proved correct? Is it true, as one well-known blogger put it, that ‘we are all multiregionalists now’ [John Hawks, NEANDERTALS LIVE! (http://johnhawks.net/weblog/reviews/neandertals/neandertal_dna/neandertals-live-genome-sequencing-2010.html) Click for link]? Should we, according to another commentator, stop talking about evolutionary trees and replace them with ‘braids’ [Professor Clive Finlayson, Viewpoint: Human evolution, from tree to braid (http://www.bbc.co.uk/news/science-environment-25559172) Click for link]? More remarkably, were RAO models, popularly known as Out of Africa models, founded on a hoax [R. Bednarik, R. African Eve: hoax or hypothesis?. Adv. Anthropol. 2013; 3: 216–228]?

parasar
05-01-2014, 04:22 PM
No, he cites the people/ideas he is fighting.

The ROoA (ie Upper Paleolithic ~50000ybp) is looking more and more doubtful. Stringer is going to lose that battle.
Both Tianyuan and Zhirendong show that the 50000ybp exit date should be abandoned. Tianyuan is 40000 years old and is already far distant from Africans. I suspect Tianyuan would be even farther from Africans of the 40000ybp period (though we need 40000ybp DNA from Africa to test this hypothesis) as current Africans have a lot of Eurasian sourced DNA. Even isolated African populations such as the San have a Eurasian input.

The Tianyuan individual differs by 21,944Ė23,756 substitutions from the Eurasian individuals (French, Sardinian, Papuan, Dai, Han, Karitiana) and by 30,297Ė35,938 substitutions from the African individuals (San, Mbuti, Yoruba, Mandenka, Dinka).

Furthermore, Tianyuan is 13,994 substitutions closer to the Karitiana than to the San. This 13,994 substitution difference is more than Tianyuan's distance from the San vis a vis the Denisovan which difference is almost half that at 7,955 substitutions.
http://rokus01.files.wordpress.com/2014/02/fu2012.jpg
Table 1 Pairwise nucleotide differences among chromosome 21 sequences analyzed
http://www.pnas.org/content/early/2013/01/17/1221359110.full.pdf

parasar
05-01-2014, 06:00 PM
Re: Zhirendong mentioned above.

For living populations the torus angularis (or process asteriacus in modern man), is
still visible in certain MongoloÔd and AustraloÔd populations with high incidence of other
bone thickenings like retromastoid process and supramastoid tubercle.

Discussion and conclusion

The time gap between late evolved Homo erectus and Anatomically Modern Human,
or Homo sapiens Linnaeus, has been filled recently with the discovery of the Chongzuo
mandible (Zhiren cave) in South China dated of 110 ka (Liu et al. 2010). Contrary to critics
questioning the possibility of a parallel emergence of modern anatomy in Asia, the release of
the trigonum mentale under the incisor dental arch that shapes the first appearance of the
mentum osseum is never visible on H. habilis, H. erectus, H. georgicus, H. antecessor, H.
heidelbergensis, and on the late Homo neanderthalensis and Homo floresiensis. The oldest
mentum osseum known before the Chinese discovery is Omo Kibish 1 (Ethiopia 200 ka) then
Qafzeh (Near East 95 ka, for instance Qafzeh 7 original mandible at IPH).
The Pleistocene Anatomically Modern Human developed cranial capacity around
1400-1600 ml, for instance as in Iberomaurusian people greater than in Holocene people, but
the brachycephaly is not visible before Mesolithic i.e. 9000 ka BP. Orsang cranial capacity
(1485 ml) corresponds to the Paleolithic peoples, while its hyperbrachycranial conformation
results of neural growth abnormalities. With its conspicuously developed glabellar
pneumatization, its well-marked post-cranial superstructures, the skull from Orsang valley is
closer to the robust Homo sapiens of the late Pleistocene than to the gracile Neolithic
populations. Besides, with its well-developed torus angularis, this skull attests to the presence
of Asian Homo erectus genes in its hereditary material and allows concluding that among
ancestors of Orsang valleys populations were late Asian Homo erectus living in the Narmada
basin, such as the large brained Homo erectus narmadensis. The paradigm of replacement by
African anatomically modern humans arriving in Asia around 90 – 70 ka and extinction of
autochthonous populations can no more be supported by recent paleontological data, the
mandible of Chongzuo in South China dated of 110 ka and the Late Pleistocene skull of
Orsang in Central India, with early Eurasian feature, the torus angularis.

http://halshs.archives-ouvertes.fr/docs/00/87/39/39/PDF/Discovery_of_a_robust_fossil_Homo_sapiens_in_India _final_version.pdf

alan
05-01-2014, 08:36 PM
I think there is a difference in accepting multiple waves and admixture with other hominids and total abandonment of Out of Africa. An especially early southern coastal route seems to have support. I think the problem is when people think of it as a simple constant fission that neatly matches the y DNA tree. I tend to think there was a cradle zone near Africa where modern humans had lived for rather longer out of Africa than we used to think and from here a southern route may have been taken very early. From here I do agree though that the dates of the first modern humans to spread across Asia is looking likely to be earlier than once posited. Its also fair to say that the idea that the technological change from middle palaeolithic tool techniques such as mousterian to classic upper palaeolithic techniques marks the change from Neanderthals or other hominids to modern humans has been very badly shaken recently. The earlier waves of modern humans do seem to have used many middle palaeolithic tool making techniques. In otherwords the makers of upper palaeolithic techniques may be modern humans but that does not mean that all modern humans used them. Initially they appear not to have. In European and north Asian terms this is shown by the groups from Siberia to Europe known an 'initial upper palaeolithic' groups who retained a lot of middle paleolithic techniques. This does suggest that some of the even earlier users of middle palaeolithic techniques in southern Asia may well have actually been modern humans - a bit of a pain for archaeologists. It may have only been specific subsets of modern humans who developed what we think of as classic upper palaeolithic techniques and perhaps from them the ideas spread.

As far as I can tell the SNP counting method is suggesting all dates may be pushed somewhat further back than once thought albeit not astronomically.

alan
05-01-2014, 09:06 PM
I read that re-dating of mtDNA pushed the possibility of an out of Africa movement back to (from memory) 75-120 thousand years ago. Does anyone know if the new ySNP counting is suggesting an early date for y lines moving out of Africa? The general pattern seems to be that that technique is pushing back dates by a significant fraction. Has anyone any data on how that effects the dating of the earliest out of Africa y DNA?

alan
05-01-2014, 09:23 PM
This is a very specialist area that I cant pretend to be well read on but I am getting the impression that a number of strands of genetic and archaeological evidence seem to suggest that a limited dispersal could have proceeded into south-west Asia by 100,000 years ago.

I think I wouldnt be too far from believing Dienekes is in the right area when he says 'All in all, I'd say that my "two deserts" theory whereby a Green Sahara pumped early modern humans to Asia prior to 100,000 years ago and then a deteriorating Arabian desert pumped them out post-70,000 years ago is not obviously wrong. Perhaps the pre-100ky wave went much further to the east, to India and Southeast Asia'. I am assuming he is saying that a probably (not certainly) limited movement into the SW fringes of Asia was followed by a more significant dispersal into south Asia.



I read that re-dating of mtDNA pushed the possibility of an out of Africa movement back to (from memory) 75-120 thousand years ago. Does anyone know if the new ySNP counting is suggesting an early date for y lines moving out of Africa? The general pattern seems to be that that technique is pushing back dates by a significant fraction. Has anyone any data on how that effects the dating of the earliest out of Africa y DNA?

GailT
05-02-2014, 04:56 AM
Two points:

1) It may be possible that there were multiple migrations of AMH out of Africa both before and after 100,000 years ago, but the question is whether earlier OoA migrations survive or were largely replaced by subsequent OoA migrations.

2) Regardless of whether the major OaA migration occurred 70,000 or 130,000 years ago, it still indicates that AMH originated in and expanded from Africa.

The traditional multiregionalism theory has been falsified based on both uniparental and autosomal DNA. At most, one can claim a very weak form of multiregionalism in that the expanding AMH population mixed with and overwhelmed existing archaic populations. I think this is the sense that John Hawks said we are all multiregionalists, i.e., that a small trace of archaic humans survive in us. But Hawks also clearly states that we are primarily descended from a recent AMH ancestor which originated in Africa. Milford Wolpoff's multiregionalism theory (that AMH evolved from an erectus ancestor that exited Africa more than 1 million years ago) is inconsistent with the DNA evidence.

It is fascinating that a small trace of archaic humans survives in us, but this in no way supports the belief (or the wish) that AMH originated outside of Africa.

parasar
05-02-2014, 05:52 PM
Two points:

1) It may be possible that there were multiple migrations of AMH out of Africa both before and after 100,000 years ago, but the question is whether earlier OoA migrations survive or were largely replaced by subsequent OoA migrations.

2) Regardless of whether the major OaA migration occurred 70,000 or 130,000 years ago, it still indicates that AMH originated in and expanded from Africa.

The traditional multiregionalism theory has been falsified based on both uniparental and autosomal DNA. At most, one can claim a very weak form of multiregionalism in that the expanding AMH population mixed with and overwhelmed existing archaic populations. I think this is the sense that John Hawks said we are all multiregionalists, i.e., that a small trace of archaic humans survive in us. But Hawks also clearly states that we are primarily descended from a recent AMH ancestor which originated in Africa. Milford Wolpoff's multiregionalism theory (that AMH evolved from an erectus ancestor that exited Africa more than 1 million years ago) is inconsistent with the DNA evidence.

It is fascinating that a small trace of archaic humans survives in us, but this in no way supports the belief (or the wish) that AMH originated outside of Africa.

What if Y-M168 originated outside Africa some 60000 years after separation from Africa and them M168's descendants swamped Africa reaching 100% in some populations? That a common ancestor of C,D,E,F migrated out of Africa followed by a back-migration of E to Africa (please see figure below with E expanding 64000ybp). In this scenario, that post-70000ybp movement is not a second move out from Africa but a movement into Africa .
I would agree with you though that if AMH is over 130000 years old then AMH has an African origin.

http://www.anthrogenica.com/attachment.php?attachmentid=1173&d=1389101515

parasar
05-04-2014, 03:19 PM
I read that re-dating of mtDNA pushed the possibility of an out of Africa movement back to (from memory) 75-120 thousand years ago. Does anyone know if the new ySNP counting is suggesting an early date for y lines moving out of Africa? The general pattern seems to be that that technique is pushing back dates by a significant fraction. Has anyone any data on how that effects the dating of the earliest out of Africa y DNA?

Depends. At the pre-CT level evolutionary is better, as lineages get more recent pedigree is closer.


. The TMRCA of all the 377 Y chromosomes estimated
using evolutionary STR mutation rates is 117-127 kya, slightly higher than sequence-based
TMRCA. However, the estimations using three genealogical mutation rates give the date almost
4-5 times lower than sequence-based TMRCA. This point is consistent with Wei et alís
observation (Wei et al., 2013a). However, the ages for other main lineages (CT, DE, K, NO, IJ, P, E,
C, I, J, N, O, and R) show large gaps with both the times estimated using evolutionary and
genealogical STR mutation rates. The times using evolutionary rates show a slightly better
correlation with the sequence-based estimation than using genealogical rates at the Y
Downloaded from http://biorxiv.org/ on May 4, 2014chromosomal main lineage level (EMR: Pearsonís r=0.892, Spearmanís rho=0.940, p=1.878E-6;
rEMR: Pearsonís r=0.872, Spearmanís rho=0.907, p=1.930E-5; OMRB: Pearsonís r= 0.878,
Spearmanís rho=0.923, p=6.852E-6; OMRS: Pearsonís r=0.865, Spearmanís rho=0.896, p=3.481E-5;
lmMR: Pearsonís r=0.860, Spearmanís rho=0.879, p=7.545E-5). For the sublineages coalesced in
Neolithic Time (C3e, and from D2a1b to R1b1a2a1a2 in x-axis of fig.2a), the TMRCAs based on
three genealogical rates are much more consistent with sequence-based TMRCAs than those
based on evolutionary rates. At the sublineages level, the ages estimated using genealogical rates
have a slightly better correlation with sequence-based estimation

http://biorxiv.org/content/biorxiv/early/2014/05/03/004705.full.pdf

Jean M
06-21-2016, 07:59 AM
https://www.youtube.com/watch?v=igrL9FypiZc

Professor Chris Stringer explains all with pictures.

9884

Homo sapiens developed from Homo heidelbergensis. That had to happen somewhere where there were Homo heidelbergensis. That rules out the Americas and Australia. Homo heidelbergensis developed from Homo erectus. That had to happen where there were Homo erectus.

Map of locations for Homo heidelbergensis and early Homo sapiens

9885

Baltimore1937
06-21-2016, 10:09 AM
I walked my ex-mother-in-law's dog a few times at the Steinheim site in Hessen. But I didn't know anything about it back then (early 1970s). The cave is locked, but with a commemorative metal plaque.