Showing posts with label China. Show all posts
Showing posts with label China. Show all posts

March 03, 2017

Incipient Mongoloids (or elusive Denisovans) 105-125kya in China?

The authors claim that these archaic humans from China show parallels to both modern eastern Eurasians (Mongoloids) and to Neandertals. The relationship with the Neandertals makes them prime candidates for the elusive Denisovans who were a sister group to Neandertals but are morphologically unknown (since all we've got is a genome, teeth, and a pinky). The relationship with Mongoloids suggest an appearance of Mongoloid morphology pre-dating the transition to sapiens, and brings to mind past claims about incipient Caucasoid morphology in Neandertals. Did aspects of modern Eurasian morphology originate in pre-sapiens archaic Eurasians? Hopefully someone's studying DNA from these crania as we speak.

Science 03 Mar 2017: Vol. 355, Issue 6328, pp. 969-972 DOI: 10.1126/science.aal2482

Late Pleistocene archaic human crania from Xuchang, China 

Zhan-Yang Li et al.

Two early Late Pleistocene (~105,000- to 125,000-year-old) crania from Lingjing, Xuchang, China, exhibit a morphological mosaic with differences from and similarities to their western contemporaries. They share pan–Old World trends in encephalization and in supraorbital, neurocranial vault, and nuchal gracilization. They reflect eastern Eurasian ancestry in having low, sagittally flat, and inferiorly broad neurocrania. They share occipital (suprainiac and nuchal torus) and temporal labyrinthine (semicircular canal) morphology with the Neandertals. This morphological combination reflects Pleistocene human evolutionary patterns in general biology, as well as both regional continuity and interregional population dynamics.

Link

August 06, 2016

China's Great Flood and the rise of the Xia dynasty

From a related story: Massive flood may have led to China's earliest empire:
Many cultures trace their origins to the hazy horizon where history meets legend. In China's case, that blurry line occurs sometime between 2200 B.C.E. and 2000 B.C.E., when a legendary hero named Yu tamed Yellow River flooding and earned a mandate to become the founding emperor of the Xia dynasty, the country's first. That’s the story according to texts written long after the fact, and many Chinese believe their civilization started with emperor Yu. But archaeologists have been unable to find convincing evidence for either the flood or the Xia dynasty itself. 
... 
The massive flood “provides us with a tantalizing hint that the Xia dynasty might really have existed," says David Cohen, an archaeologist and co-author at National Taiwan University in Taipei. The devastating flood could have inundated settlements even a thousand or more kilometers downstream, he says, and created chaos from which a new political order emerged. This sequence of events neatly fits the legend of Yu controlling the flooding by dredging channels to confine the Yellow River and its tributaries. This feat, the ancient texts say, allowed him to claim a mandate as the first emperor of the Xia dynasty.  
The timing is curiously coincidental. Around 1900 B.C.E., Cohen says, Chinese society was transitioning from the Neolithic to the Bronze age. The date also correlates with what is called the Erlitou culture, which is known from palace buildings and bronze smelting workshops discovered near Zhengzhou, about 2500 kilometers downstream from Jishi Gorge. Many scholars have argued that Erlitou is a manifestation of the elusive Xia dynasty, but a link is not firmly established.

Science 05 Aug 2016: Vol. 353, Issue 6299, pp. 579-582 DOI: 10.1126/science.aaf0842

Outburst flood at 1920 BCE supports historicity of China’s Great Flood and the Xia dynasty

Qinglong Wu

China’s historiographical traditions tell of the successful control of a Great Flood leading to the establishment of the Xia dynasty and the beginning of civilization. However, the historicity of the flood and Xia remain controversial. Here, we reconstruct an earthquake-induced landslide dam outburst flood on the Yellow River about 1920 BCE that ranks as one of the largest freshwater floods of the Holocene and could account for the Great Flood. This would place the beginning of Xia at ~1900 BCE, several centuries later than traditionally thought. This date coincides with the major transition from the Neolithic to Bronze Age in the Yellow River valley and supports hypotheses that the primary state-level society of the Erlitou culture is an archaeological manifestation of the Xia dynasty.

Link

April 01, 2016

Zhiren cave human remains: 116-106 ka old

Quaternary International doi:10.1016/j.quaint.2015.12.088

The age of human remains and associated fauna from Zhiren Cave in Guangxi, southern China

Yanjun Cai et al.

Zhiren Cave in southern China is an important site for the study of the origin and the environmental background of early modern humans. The combination of Elephas kiangnanensis, Elephas maximus, and Megatapirus augustus, indicates an early representative of the typical Asian elephant fauna. Previous U-series dating of flowstone calcite has pinpointed an upper age limit for the fossils of about 100 ka. In order to achieve a better comprehension of the chronology of the modern human and contemporaneous faunal assemblage, paleomagnetic, stratigraphic, and optically stimulated luminescence (OSL) dating methods have been applied to the cave sediments. Paleomagnetic analyses reveal that there is a reversed polarity excursion below the fossiliferous layer. This excursion can be regarded as the Blake excursion event, given the U-series ages of the overlying flowstone calcite, the OSL measurements, the virtual geomagnetic pole (VGP) path of the excursion, the two reverse polarity zones within this excursion event, and the characteristic of the fauna assemblage. The human remains and mammalian fauna assemblage can be bracketed to 116–106 ka. Application of OSL dating leads to erroneous ages, largely due to the uncertainty associated with the estimation on the dose rates.

Link

December 18, 2015

Archaic femur from Maludong, China

PLoS ONE 10(12): e0143332. doi:10.1371/journal.pone.0143332

A Hominin Femur with Archaic Affinities from the Late Pleistocene of Southwest China

Darren Curnoe et al.

The number of Late Pleistocene hominin species and the timing of their extinction are issues receiving renewed attention following genomic evidence for interbreeding between the ancestors of some living humans and archaic taxa. Yet, major gaps in the fossil record and uncertainties surrounding the age of key fossils have meant that these questions remain poorly understood. Here we describe and compare a highly unusual femur from Late Pleistocene sediments at Maludong (Yunnan), Southwest China, recovered along with cranial remains that exhibit a mixture of anatomically modern human and archaic traits. Our studies show that the Maludong femur has affinities to archaic hominins, especially Lower Pleistocene femora. However, the scarcity of later Middle and Late Pleistocene archaic remains in East Asia makes an assessment of systematically relevant character states difficult, warranting caution in assigning the specimen to a species at this time. The Maludong fossil probably samples an archaic population that survived until around 14,000 years ago in the biogeographically complex region of Southwest China.

Link

October 15, 2015

Modern humans in China ~80,000 years ago (?)

Another (?)-worthy paper has just appeared in Nature in the heels of the African ancient genome paper. Time will tell how these worldview-altering discoveries will change the story of Mankind, and a degree of skepticism is warranted. In the view I've held for a few years, modern humans expanded to Arabia before 100 thousand years ago, started leaving it 70 thousand years ago as the ecological situation worsened due to desertification and broke through the "Neandertal barrier" between 70-50 thousand years ago when they developed the skills and technology to overcome them.

The new paper claims that modern humans were in China 80 thousand years ago and came to Europe much later because Neandertal represented a barrier to successful entry to Europe. This begs the question of how they reached China without encountering Neandertals, as Neandertals were also in West Asia where -presumably- they passed through to get to China. A coastal route to south China would explain away this problem, but the coastal migration is usually envisioned much later, at around 60 thousand years ago. On top of that, how did Chinese end up having equal (or more) levels of Neandertals admixture if modern humans first went to China and later moved west and successfully outcompeted the Neandertals. How were they able to do so eventually? (There is no evidence that the kind of advantages associated with behavioral modernity first emerged in East Asia). It's possible that there were 80 thousand year-old modern humans in China (just as there were 100 thousand year-old modern humans in Israel), but that the later East Asians are not descended from them.

One would think that science would present an increasingly reasonable and consistent picture of the past, but it seems that we're a very long way from the point where the dust settles and the puzzle pieces start falling into place.

Nature (2015) doi:10.1038/nature15696

The earliest unequivocally modern humans in southern China

Wu Liu, María Martinón-Torres, Yan-jun Cai, Song Xing, Hao-wen Tong, Shu-wen Pei, Mark Jan Sier, Xiao-hong Wu, R. Lawrence Edwards, Hai Cheng, Yi-yuan Li, Xiong-xin Yang, José María Bermúdez de Castro & Xiu-jie Wu

The hominin record from southern Asia for the early Late Pleistocene epoch is scarce. Well-dated and well-preserved fossils older than ~45,000 years that can be unequivocally attributed to Homo sapiens are lacking1, 2, 3, 4. Here we present evidence from the newly excavated Fuyan Cave in Daoxian (southern China). This site has provided 47 human teeth dated to more than 80,000 years old, and with an inferred maximum age of 120,000 years. The morphological and metric assessment of this sample supports its unequivocal assignment to H. sapiens. The Daoxian sample is more derived than any other anatomically modern humans, resembling middle-to-late Late Pleistocene specimens and even contemporary humans. Our study shows that fully modern morphologies were present in southern China 30,000–70,000 years earlier than in the Levant and Europe5, 6, 7. Our data fill a chronological and geographical gap that is relevant for understanding when H. sapiens first appeared in southern Asia. The Daoxian teeth also support the hypothesis that during the same period, southern China was inhabited by more derived populations than central and northern China. This evidence is important for the study of dispersal routes of modern humans. Finally, our results are relevant to exploring the reasons for the relatively late entry of H. sapiens into Europe. Some studies have investigated how the competition with H. sapiens may have caused Neanderthals’ extinction (see ref. 8 and references therein). Notably, although fully modern humans were already present in southern China at least as early as ~80,000 years ago, there is no evidence that they entered Europe before ~45,000 years ago. This could indicate that H. neanderthalensis was indeed an additional ecological barrier for modern humans, who could only enter Europe when the demise of Neanderthals had already started.

Link

July 12, 2015

mtDNA from Xiaohe cemetery

BMC Genetics 2015, 16:78 doi:10.1186/s12863-015-0237-5

Analysis of ancient human mitochondrial DNA from the Xiaohe cemetery: insights into prehistoric population movements in the Tarim Basin, China

Chunxiang Li et al.

Abstract

Background

The Tarim Basin in western China, known for its amazingly well-preserved mummies, has been for thousands of years an important crossroad between the eastern and western parts of Eurasia. Despite its key position in communications and migration, and highly diverse peoples, languages and cultures, its prehistory is poorly understood. To shed light on the origin of the populations of the Tarim Basin, we analysed mitochondrial DNA polymorphisms in human skeletal remains excavated from the Xiaohe cemetery, used by the local community between 4000 and 3500 years before present, and possibly representing some of the earliest settlers.

Results

Xiaohe people carried a wide variety of maternal lineages, including West Eurasian lineages H, K, U5, U7, U2e, T, R*, East Eurasian lineages B, C4, C5, D, G2a and Indian lineage M5.

Conclusion

Our results indicate that the people of the Tarim Basin had a diverse maternal ancestry, with origins in Europe, central/eastern Siberia and southern/western Asia. These findings, together with information on the cultural context of the Xiaohe cemetery, can be used to test contrasting hypotheses of route of settlement into the Tarim Basin.

Link

May 03, 2015

Structure of Y-haplogroup N

arXiv:1504.06463 [q-bio.PE]

The dichotomy structure of Y chromosome Haplogroup N

Kang Hu et al.

Haplogroup N-M231 of human Y chromosome is a common clade from Eastern Asia to Northern Europe, being one of the most frequent haplogroups in Altaic and Uralic-speaking populations. Using newly discovered bi-allelic markers from high-throughput DNA sequencing, we largely improved the phylogeny of Haplogroup N, in which 16 subclades could be identified by 33 SNPs. More than 400 males belonging to Haplogroup N in 34 populations in China were successfully genotyped, and populations in Northern Asia and Eastern Europe were also compared together. We found that all the N samples were typed as inside either clade N1-F1206 (including former N1a-M128, N1b-P43 and N1c-M46 clades), most of which were found in Altaic, Uralic, Russian and Chinese-speaking populations, or N2-F2930, common in Tibeto-Burman and Chinese-speaking populations. Our detailed results suggest that Haplogroup N developed in the region of China since the final stage of late Paleolithic Era.

Link

January 01, 2015

Y Chromosome of Aisin Gioro: C3b2b1

Apart from the historical interest, this study might be useful to further calibrate the Y-chromosome molecular clock. The Y-SNP mutation rate was previously calibrated with a Chinese pedigree that went down to ~1800AD, and this is potentially much deeper.

arXiv:1412.6274 [q-bio.PE]

Y Chromosome of Aisin Gioro, the Imperial House of Qing Dynasty 

Shi Yan, Harumasa Tachibana, Lan-Hai Wei, Ge Yu, Shao-Qing Wen, Chuan-Chao Wang

(Submitted on 19 Dec 2014) House of Aisin Gioro is the imperial family of the last dynasty in Chinese history - Qing Dynasty (1644 - 1911). Aisin Gioro family originated from Jurchen tribes and developed the Manchu people before they conquered China. By investigating the Y chromosomal short tandem repeats (STRs) of 7 modern male individuals who claim belonging to Aisin Gioro family (in which 3 have full records of pedigree), we found that 3 of them (in which 2 keep full pedigree, whose most recent common ancestor is Nurgaci) shows very close relationship (1 - 2 steps of difference in 17 STR) and the haplotype is rare. We therefore conclude that this haplotype is the Y chromosome of the House of Aisin Gioro. Further tests of single nucleotide polymorphisms (SNPs) indicates that they belong to Haplogroup C3b2b1*-M401(xF5483), although their Y-STR results are distant to the "star cluster", which also belongs to the same haplogroup. This study forms the base for the pedigree research of the imperial family of Qing Dynasty by means of genetics.

Link

Ancient DNA from Di-qiang populations in the Xinjiang

American Journal of Physical Anthropology DOI: 10.1002/ajpa.22690

Ancient DNA reveals a migration of the ancient Di-qiang populations into Xinjiang as early as the early Bronze Age

Shi-Zhu Gao et al.

Xinjiang is at the crossroads between East and West Eurasia, and it harbors a relatively complex genetic history. In order to better understand the population movements and interactions in this region, mitochondrial and Y chromosome analyses on 40 ancient human remains from the Tianshanbeilu site in eastern Xinjiang were performed. Twenty-nine samples were successfully assigned to specific mtDNA haplogroups, including the west Eurasian maternal lineages of U and W and the east Eurasian maternal lineages of A, C, D, F, G, Z, M7, and M10. In the male samples, two Y chromosome haplogroups, C* and N1 (xN1a, N1c), were successfully assigned. Our mitochondrial and Y-chromosomal DNA analyses combined with the archaeological studies revealed that the Di-qiang populations from the Hexi Corridor had migrated to eastern Xinjiang and admixed with the Eurasian steppe populations in the early Bronze Age.

Link

August 21, 2014

Ancient Y-DNA from China

From the paper:
Dividing the samples further using social status shows that the six aristocrats had haplogroups Q1a1, O3a, and N, the 14 commoners had haplogroups Q1a1, O3a, and O*, and the seven slaves had haplogroups O3a, O2a, and O* (Fig. 2).
Am. J. Hum. Biol. DOI: 10.1002/ajhb.22604

Ancient DNA evidence reveals that the Y chromosome haplogroup Q1a1 admixed into the Han Chinese 3,000 years ago

Yong-Bin Zhao et al.

Objectives

Y chromosome haplogroup Q1a1 is found almost only in Han Chinese populations. However, it has not been found in ancient Han Chinese samples until now. Thus, the origin of haplogroup Q1a1 in Han Chinese is still obscure. This study attempts to provide answer to this question, and to uncover the origin and paternal genetic structure of the ancestors of the Han Chinese.

Methods

Eighty-nine ancient human remains that were excavated from the presumed geographic source of the Han Chinese and dated to approximately 3,000 years ago were treated by the amelogenin gene polymerase chain reaction test, to determine their sex. Then, Y chromosome single nucleotide polymorphisms were subsequently analyzed from the samples detected as male.

Results 

Samples from 27 individuals were successfully amplified. Their haplotypes could be attributed to haplogroups N, O*, O2a, O3a, and Q1a1. Analyses showed that the assigned haplogroup of each sample is correlated to the suspected social status and observed burial custom associated with the sample.

Conclusions

The origins of the observed haplotypes and their distribution in present day Han Chinese and in the samples suggest that haplogroup Q1a1 was probably introduced into the Han Chinese population approximately 3,000 years ago. Am. J. Hum. Biol., 2014. © 2014 Wiley Periodicals, Inc.

Link

August 15, 2014

ISBA 2014 titles

Some interesting talks and posters from the upcoming International Symposium on Biomolecular Archaeology. I don't see any abstracts on the site (yet?) but the titles are intriguing. Some that caught my eye:

  • Investigating the maternal lineage diversity from an early medieval site in Southern Italy
  • Ancient mitochondrial and Y chromosomal DNA reveals the western Carpathian Basin as a corridor of the Neolithic expansion
  • Ancient mitochondrial DNA from the Northern fringe of the Neolithic farming expansion in Europe sheds light on the dispersion process
  • The effect of demography and natural selection on pigmentation heterogeneity in late Pleistocene and early Holocene Europeans
  • The genomics of equine speciation and domestication
  • Ancient population genetics: new insights on horse domestication
  • Species identification and analysis of the Tyrolean Iceman's clothes using next generation sequencing of ancient DNA.
  • Early evidence for the use of pottery: extending the ancient lipid record to the Pleistocene.
  • Whey to go – first identification of lactose in prehistoric pottery
  • Use of the earliest pottery on the Western and Eastern side of the Baltic
  • The geographical distribution of the Polynesian cultural complex and its association with P33-C2a1 Y chromosomes: adding data from Aotearoa (New Zealand)
  • Interdisciplinary investigation of an archaic hominin femur from the Swabian Jura (South-West Germany)
  • Tracing the genetic history of farming populations of El Portalón Cave in the Sierra de Atapuerca, Spain.
  • Ancient human genomes suggest three ancestral populations for present-day Europeans
  • Ancient DNA from Early Neolithic farmers in Europe
  • Genomic diversity and admixture in Stone-Age farmer and hunter-gatherer groups in Scandinavia
  • Ancient DNA reveals the complex genetic history of the New World Arctic
  • A prediction of the hybridisation potential between Hominin species using mitochondrial DNA
  • Population Genomics of Vikings
  • Tracing the genetic profile of Sus scrofa on Romanian territory from the Neolithic period until the Middle Ages
  • The origins of the Aegean palatial civilizations from a population genetic perspective
  • Ancient DNA evidence for a diversified origin of ancestor of Han Chinese

July 08, 2014

Neandertal-like temporal labyrinth of Xujiayao 15

From the press release:
While it's tempting to use the finding of a Neandertal-shaped labyrinth in an otherwise distinctly "non-Neandertal" sample as evidence of population contact (gene flow) between central and western Eurasian Neandertals and eastern archaic humans in China, Trinkaus and colleagues argue that broader implications of the Xujiayao discovery remain unclear.  
"The study of human evolution has always been messy, and these findings just make it all the messier," Trinkaus said. "It shows that human populations in the real world don't act in nice simple patterns.  
"Eastern Asia and Western Europe are a long way apart, and these migration patterns took thousands of years to play out," he said. "This study shows that you can't rely on one anatomical feature or one piece of DNA as the basis for sweeping assumptions about the migrations of hominid species from one place to another."
I think this study highlights the possibility that some of the traits thought to be characteristic of Neandertals may in fact be part of Eurasian hominins in general, and the fact that they have been associated with Neandertals is a consequence of the much greater attention paid to that species until recently. As East Eurasian Pleistocene Homo becomes better described, it may become clear what are indeed the traits that were specific to H. neanderthalensis.

PNAS doi: 10.1073/pnas.1410735111

Temporal labyrinths of eastern Eurasian Pleistocene humans

Xiu-Jie Wu et al.

One of the morphological features that has been identified as uniquely derived for the western Eurasian Neandertals concerns the relative sizes and positions of their semicircular canals. In particular, they exhibit a relatively small anterior canal, a relatively larger lateral one, and a more inferior position of the posterior one relative to the lateral one. These discussions have not included full paleontological data on eastern Eurasian Pleistocene human temporal labyrinths, which have the potential to provide a broader context for assessing Pleistocene Homo trait polarities. We present the temporal labyrinths of four eastern Eurasian Pleistocene Homo, one each of Early (Lantian 1), Middle (Hexian 1), and Late (Xujiayao 15) Pleistocene archaic humans and one early modern human (Liujiang 1). The labyrinths of the two earlier specimens and the most recent one conform to the proportions seen among western early and recent modern humans, reinforcing the modern human pattern as generally ancestral for the genus Homo. The labyrinth of Xujiayao 15 is in the middle of the Neandertal variation and separate from the other samples. This eastern Eurasian labyrinthine dichotomy occurs in the context of none of the distinctive Neandertal external temporal or other cranial features. As such, it raises questions regarding possible cranial and postcranial morphological correlates of Homo labyrinthine variation, the use of individual “Neandertal” features for documenting population affinities, and the nature of late archaic human variation across Eurasia.

Link

May 08, 2014

Psychological differences in China predicted by rice/wheat agriculture

Science 9 May 2014: Vol. 344 no. 6184 pp. 603-608
DOI: 10.1126/science.1246850

Large-Scale Psychological Differences Within China Explained by Rice Versus Wheat Agriculture

T. Talhelm et al.

Cross-cultural psychologists have mostly contrasted East Asia with the West. However, this study shows that there are major psychological differences within China. We propose that a history of farming rice makes cultures more interdependent, whereas farming wheat makes cultures more independent, and these agricultural legacies continue to affect people in the modern world. We tested 1162 Han Chinese participants in six sites and found that rice-growing southern China is more interdependent and holistic-thinking than the wheat-growing north. To control for confounds like climate, we tested people from neighboring counties along the rice-wheat border and found differences that were just as large. We also find that modernization and pathogen prevalence theories do not fit the data.

Link

November 08, 2013

Early cattle management in NE China

From the paper:
The haplogroup retrieved has so far not been found in modern cattle. However, as mtDNA represents a single genetic locus, it is prone to genetic drift and could easily have been lost by drift even if hybridization between the population to which the Chinese specimen belonged and other domesticated cattle populations has occurred. Further analyses on nuclear DNA will be necessary to show whether this early Chinese cattle management was a short-lived episode or whether it has contributed to the nuclear gene pool of modern cattle.

Nature Communications 4, Article number: 2755 doi:10.1038/ncomms3755

Morphological and genetic evidence for early Holocene cattle management in northeastern China

Hucai Zhang et al.

The domestication of cattle is generally accepted to have taken place in two independent centres: around 10,500 years ago in the Near East, giving rise to modern taurine cattle, and two millennia later in southern Asia, giving rise to zebu cattle. Here we provide firmly dated morphological and genetic evidence for early Holocene management of taurine cattle in northeastern China. We describe conjoining mandibles from this region that show evidence of oral stereotypy, dated to the early Holocene by two independent 14C dates. Using Illumina high-throughput sequencing coupled with DNA hybridization capture, we characterize 15,406 bp of the mitogenome with on average 16.7-fold coverage. Phylogenetic analyses reveal a hitherto unknown mitochondrial haplogroup that falls outside the known taurine diversity. Our data suggest that the first attempts to manage cattle in northern China predate the introduction of domestic cattle that gave rise to the current stock by several thousand years.

Link

October 29, 2013

Interesting talks @ Penn: Zheng He and Mount Vesuvius

I had recently mentioned Zheng He on account of his Y chromosome.

Great Voyages: Zheng He


Pompeii Lecture Series: Mount Vesuvius in Human History

October 22, 2013

A Persian in China (Y chromosome of Sayyid Ajjal)

Quite remarkable that a Persian (Sayyid Ajjal) would leave many descendants in faraway China, and one of this descendants (Zheng He) would one day set out to explore the West (from the perspective of China). A nice reminder of how far a Y-chromosome lineage might travel, even in the span of a couple of centuries.

arXiv:1310.5466 [q-bio.PE]

Present Y chromosomes support the Persian ancestry of Sayyid Ajjal Shams al-Din Omar and Eminent Navigator Zheng He

Chuan-Chao Wang et al.

Sayyid Ajjal is the ancestor of many Muslims in areas all across China. And one of his descendants is the famous Navigator of Ming Dynasty, Zheng He, who led the largest armada in the world of 15th century. The origin of Sayyid Ajjal's family remains unclear although many studies have been done on this topic of Muslim history. In this paper, we studied the Y chromosomes of his present descendants, and found they all have haplogroup L1a-M76, proving a southern Persian origin.

Link

October 16, 2013

Neolithic super-grandfathers of the Chinese

An interesting new paper on the arXiv. The title focuses on three star-like Neolithic expansions that account for ~40% of the modern Chinese. From ~3 men to ~270 million male descendants over ~6,000 years ain't too shabby.

Also of interest in the paper is the authors' work on the rest of the Y-chromosome tree (see Figure on the left). As always with age estimates, the details matter. From the paper:
It is worth to point out that
recently, Wei et al. published a similar study about Y chromosome sequencing of 36 individuals (mainly Haplogroup R1b and E1b), in which 3.15 or 8.83 Mbp range was sequenced 19, and they achieved a time of out-of-Africa at 57 – 74 kya using various methods, which is slightly older than our result  (54 kya), although the same mutation rate of 1×10-9 substitution/base/year were employed. The difference could be ascribed to the regions chosen for date estimation; we compared the regions that Wei et al. and we studied, and found that in their study, the SNP density in the region that was sequenced only in their study is significantly higher than that in the region that both studies have sequenced (P less than 0.005) (Table S3).

It thus seems that the time estimates may be lower than true. An interesting new finding from the paper is the near-simultaneous D/CF and C/F splits. The authors comment:
It remained mysterious that how many times the anatomically modern human migrated out of Africa, since that among the three superhaplogrous C, DE and F, Haplogroup F distributes in whole Eurasia, C in Asia and Austronesia, D exclusively in Asia, while D’s brother clade E distribute mainly in Africa 62, so there are two hypotheses, 1) haplogroups D and CF migrated out of Africa separately; 2) the single common ancestor of CF and DE migrated out of Africa followed by a back-migration of E to Africa. From this study, the short interval between CF/DE and C/F divergences weakens the possibility of multiple independent migrations (CF, D, and DE*) out of Africa, and thus supports the latter hypothesis 63 (Fig. S2 a).
I have argued for haplogroup E back-migration into Africa before in this blog, so it's nice to see that this idea is gaining some supporters.

arXiv:1310.3897v1 [q-bio.PE]

Y Chromosomes of 40% Chinese Are Descendants of Three Neolithic Super-grandfathers

Shi Yan et al.

Demographic change of human populations is one of the central questions for delving into the past of human beings. To identify major population expansions related to male lineages, we sequenced 78 East Asian Y chromosomes at 3.9 Mbp of the non-recombining region (NRY), discovered >4,000 new SNPs, and identified many new clades. The relative divergence dates can be estimated much more precisely using molecular clock. We found that all the Paleolithic divergences were binary; however, three strong star-like Neolithic expansions at ~6 kya (thousand years ago) (assuming a constant substitution rate of 1e-9/bp/year) indicates that ~40% of modern Chinese are patrilineal descendants of only three super-grandfathers at that time. This observation suggests that the main patrilineal expansion in China occurred in the Neolithic Era and might be related to the development of agriculture.

Link

October 12, 2013

Ancient Y chromosomes of West Liao River valley

I added the results in my compendium.

BMC Evolutionary Biology 2013, 13:216 doi:10.1186/1471-2148-13-216

Y Chromosome analysis of prehistoric human populations in the West Liao River Valley, Northeast China

Yinqiu Cui et al.

Abstract

Background

The West Liao River valley in Northeast China is an ecologically diverse region, populated in prehistory by human populations with a wide range of cultures and modes of subsistence. To help understand the human evolutionary history of this region, we performed Y chromosome analyses on ancient human remains from archaeological sites ranging in age from 6500 to 2700 BP.

Results

47 of the 70 individuals provided reproducible results. They were assigned into five different Y sub-haplogroups using diagnostic single nucleotide polymorphisms, namely N1 (xN1a, N1c), N1c, C/C3e, O3a (O3a3) and O3a3c. We also used 17 Y short tandem repeat loci in the non-recombining portion of the Y chromosome. There appears to be significant genetic differences between populations of the West Liao River valley and adjacent cultural complexes in the prehistoric period, and these prehistoric populations were shown to carry similar haplotypes as present-day Northeast Asians, but at markedly different frequencies.

Conclusion

Our results suggest that the prehistoric cultural transitions were associated with immigration from the Yellow River valley and the northern steppe into the West Liao River valley. They reveal the temporal continuity of Y chromosome lineages in populations of the West Liao River valley over 5000 years, with a concurrent increase in lineage diversity caused by an influx of immigrants from other populations.

Link

July 18, 2013

81-100 thousand year old modern humans from China

From the paper:
The presumption of a late appearance of AMH in eastern Asia has been largely prompted by a remarkable yet dubious ‘gap’ between 100 and 40 ka ago lacking any human fossils, specifically between the latest archaic H. sapiens (i.e., Xujiayao, 104–125 ka and Maba, 129–135 ka) and the earliest modern H. sapiens (i.e., Ziyang, 35-40 ka) (data pooled from Wu and Poirier, 1995). In addition, genetic studies of present-day Chinese populations have supported the late appearance of AMH in eastern Asia (e.g., Chu et al., 1998). From this perspective, the AMH fossils from Tianyuan Cave at Zhoukoudian in northern China, dated to 39-42 ka B.P. (Before Present), have been readily accepted as the earliest representatives of modern H. sapiens in China, and the earliest evidence for the influx of African genes into the indigenous population (e.g., Shang et al., 2007; Cartmill and Smith, 2009; Endicott et al., 2009). 
However, the credibility of this supposed ~60 ka gap in the hominin fossil record and a late appearance of modern humans in China might have been compromised by the exclusion of a number of hominin fossils claimed to represent AMH from various limestone caves in southern China with more ancient dates, including Liujiang (between 68 and 153 ka, and most probably between 111 and 139 ka, Shen et al., 2002b), Ganqian (94–220 ka, Shen et al., 2002a), Bailiandong (>160 ka, Shen et al., 2001b), and Zhirendong (>100 ka, Liu et al., 2010a) in Guangxi. Based on our work on the sites of H. erectus and of both archaic and modern H. sapiens over the past twenty plus years, we argue that the temporal framework in China has been artificially ‘compressed and gapped,’ meaning that due to limitations in previous dating techniques and practices, the ages of Chinese hominin fossils have been significantly postdated (compressed), and that a temporal gap between archaic H. sapiens and AMH has been artificially created (gapped). To this scenario of the possible early presence of modern humans in China, here we report evidence from Huanglong Cave, a recently discovered Late Pleistocene hominin fossil- and stone artifact-bearing site, and discuss its impact on the mode of recent human evolution in eastern Asia.
I guess a lot depends on whether these teeth are accepted as belonging to AMH; if this holds, the early range of AMH must need to be extended even further east.

Such early dates are often seen as conflicting with the molecular clock (e.g., West and East Eurasians don't appear to have diverged ~100 thousand years ago no matter what assumptions about mutation rate one makes). But, we should not forget that divergence times can be suppressed either due to (i) admixture between the divergent populations, or (ii) due to an expansion of a highly successful population.


Journal of Human Evolution doi:10.1016/j.jhevol.2013.05.002

Mass spectrometric U-series dating of Huanglong Cave in Hubei Province, central China: Evidence for early presence of modern humans in eastern Asia

Guanjun Shen et al.

Most researchers believe that anatomically modern humans (AMH) first appeared in Africa 160-190 ka ago, and would not have reached eastern Asia until ∼50 ka ago. However, the credibility of these scenarios might have been compromised by a largely inaccurate and compressed chronological framework previously established for hominin fossils found in China. Recently there has been a growing body of evidence indicating the possible presence of AMH in eastern Asia ca. 100 ka ago or even earlier. Here we report high-precision mass spectrometric U-series dating of intercalated flowstone samples from Huanglong Cave, a recently discovered Late Pleistocene hominin site in northern Hubei Province, central China. Systematic excavations there have led to the in situ discovery of seven hominin teeth and dozens of stone and bone artifacts. The U-series dates on localized thin flowstone formations bracket the hominin specimens between 81 and 101 ka, currently the most narrow time span for all AMH beyond 45 ka in China, if the assignment of the hominin teeth to modern Homo sapiens holds. Alternatively this study provides further evidence for the early presence of an AMH morphology in China, through either independent evolution of local archaic populations or their assimilation with incoming AMH. Along with recent dating results for hominin samples from Homo erectus to AMH, a new extended and continuous timeline for Chinese hominin fossils is taking shape, which warrants a reconstruction of human evolution, especially the origins of modern humans in eastern Asia.

Link

June 21, 2013

Origins and dispersals of Y-chromosome haplogroup N

I will simply note that the authors use the effective mutation rate that is ~1/3 the genealogical mutation rate and hence their age estimates are inflated by ~3x. I have expressed reservations about using Y-STR based age estimates in general, but these concerns become more important for older lineages.

In particular, I would be very surprised if Y-haplogroup N turns up in Europe 8-10 thousand years ago, and I expect to see it make its first appearance in the 3rd millennium BC or thereabouts, perhaps together with the Seima-Turbino expansion across northern Eurasia. Thanks to the ancient DNA -preserving boreal cold, it may be possible to find out.

Irrespective of my disagreement on the mutation rate issue, I have to applaud the comprehensive survey carried out by these Chinese scientists: numbers invariably pay off.

PLoS ONE 8(6): e66102. doi:10.1371/journal.pone.0066102

Genetic Evidence of an East Asian Origin and Paleolithic Northward Migration of Y-chromosome Haplogroup N

Hong Shi et al.

The Y-chromosome haplogroup N-M231 (Hg N) is distributed widely in eastern and central Asia, Siberia, as well as in eastern and northern Europe. Previous studies suggested a counterclockwise prehistoric migration of Hg N from eastern Asia to eastern and northern Europe. However, the root of this Y chromosome lineage and its detailed dispersal pattern across eastern Asia are still unclear. We analyzed haplogroup profiles and phylogeographic patterns of 1,570 Hg N individuals from 20,826 males in 359 populations across Eurasia. We first genotyped 6,371 males from 169 populations in China and Cambodia, and generated data of 360 Hg N individuals, and then combined published data on 1,210 Hg N individuals from Japanese, Southeast Asian, Siberian, European and Central Asian populations. The results showed that the sub-haplogroups of Hg N have a distinct geographical distribution. The highest Y-STR diversity of the ancestral Hg N sub-haplogroups was observed in the southern part of mainland East Asia, and further phylogeographic analyses supports an origin of Hg N in southern China. Combined with previous data, we propose that the early northward dispersal of Hg N started from southern China about 21 thousand years ago (kya), expanding into northern China 12–18 kya, and reaching further north to Siberia about 12–14 kya before a population expansion and westward migration into Central Asia and eastern/northern Europe around 8.0–10.0 kya. This northward migration of Hg N likewise coincides with retreating ice sheets after the Last Glacial Maximum (22–18 kya) in mainland East Asia.

Link