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O3a3c* (M134+, M117-)
原始文献在此,Genome-wide data substantiate Holocene gene flow from India to Australia
http://www.pnas.org/content/early/2013/01/09/1211927110
O3a3c* (M134+, M117-)
Abstract
The Australian continent holds some of the earliest archaeological evidence for the expansion of modern humans out of Africa, with initial occupation at least 40,000 y ago. It is commonly assumed that Australia remained largely isolated following initial colonization, but the genetic history of Australians has not been explored in detail to address this issue. Here, we analyze large-scale genotyping data from aboriginal Australians, New Guineans, island Southeast Asians and Indians. We find an ancient association between Australia, New Guinea, and the Mamanwa (a Negrito group from the Philippines), with divergence times for these groups estimated at 36,000 y ago, and supporting the view that these populations represent the descendants of an early “southern route” migration out of Africa, whereas other populations in the region arrived later by a separate dispersal. We also detect a signal indicative of substantial gene flow between the Indian populations and Australia well before European contact, contrary to the prevailing view that there was no contact between Australia and the rest of the world. We estimate this gene flow to have occurred during the Holocene, 4,230 y ago. This is also approximately when changes in tool technology, food processing, and the dingo appear in the Australian archaeological record, suggesting that these may be related to the migration from India.
O3a3c* (M134+, M117-)
Abstract
The Australian continent holds some of the earliest archaeological evidence for the expansion of modern humans out of Africa, with initial occupation at least 40,000 y ago. It is commonly assumed that Australia remained largely isolated following initial colonization, but the genetic history of Australians has not been explored in detail to address this issue. Here, we analyze large-scale genotyping data from aboriginal Australians, New Guineans, island Southeast Asians and Indians. We find an ancient association between Australia, New Guinea, and the Mamanwa (a Negrito group from the Philippines), with divergence times for these groups estimated at 36,000 y ago, and supporting the view that these populations represent the descendants of an early “southern route” migration out of Africa, whereas other populations in the region arrived later by a separate dispersal. We also detect a signal indicative of substantial gene flow between the Indian populations and Australia well before European contact, contrary to the prevailing view that there was no contact between Australia and the rest of the world. We estimate this gene flow to have occurred during the Holocene, 4,230 y ago. This is also approximately when changes in tool technology, food processing, and the dingo appear in the Australian archaeological record, suggesting that these may be related to the migration from India.
O3a3c* (M134+, M117-)
文章没有说来自的印度的主要YSNP是啥,难道是C4?

原文大概意思是这样吧:
大约于4万年前,澳大利亚及新几内亚土著,菲律宾Mamanwa(Negrio部落)等是最早走南线出非洲的现代人群体,以前观点认为,澳大利亚土著在欧洲殖民者到来之前,几乎与世隔绝,没与其他大陆的人有什么联系。最近基因学家通过分析印度和澳洲北部地区的土著的基因序列,发现4230年前,这两个地方人群有基因交流。并且也和澳洲这一时期突然出现的石器工具,食品加工的改变,以及出现类似印度的野狗吻合,说明这些是从印度带过来的。
我之前多次提过这个问题,澳洲现代人动辄5-6万年前就登陆的论点并不靠谱。
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5# ranger
以前就有很明显的迹象表明澳洲土著在1万年之内和大陆有过基因交流,但是4230年前和印度土著有过交流确实没想到。
5# ranger  
以前就有很明显的迹象表明澳洲土著在1万年之内和大陆有过基因交流,但是4230年前和印度土著有过交流确实没想到。
wolfgang 发表于 2013-1-17 19:51
旧的文献中的ASI现已分成三个成份:Onge/Greater Andeman (Fig.3B中的黄色); New Geinua (Fig.3B中的黑色); Dravidian speakers (Fig.3B中的桔色).  桔色成分恐非真正的“印度土著”。
8# fjnj
看不到具体文献,无法讨论。在大东亚人群常染的文章里,美拉尼西亚人的常染部分确实和印度土著有同种颜色的成分,此时菲律宾尼格利陀人群和马来西亚尼格利托人群的特色常染均已分离。所以没看到具体资料前,只能说一切皆有可能。
The pdf is too big to post.  Here is the Fig.3B
Fig3B.png
本帖最后由 wolfgang 于 2013-1-18 00:46 编辑

10# fjnj
这张图是以印度人群特别是南印度人群为主要采样对象的。比较遗憾的是,边界人群选择的不好,没有中东人群和典型的蒙古利亚人群,也没有马来西亚的尼格利托人群,这样有些成分到底是什么就不好判断。根据我的感觉,其中的桔色成分有些来自中东,确实不是真正的印度土著成分。不过在澳洲土著中的成分应该不是来自历史时期。问题在于,这种成分到底来自晚近的移民还是远古时期的共同成分很难界定。不知道那个4230年是怎么来的?
11# wolfgang
Admixture-Time Estimation. We next analyzed the genome-wide
admixture pattern to estimate the time of admixture. We first
used StepPCO (20) to obtain the block-like admixture signal
across each chromosome for each Australian (excluding two
individuals with evidence of European admixture). The NGH
and India (represented, again, by Chenchu and Kurumba and the
nontribal Dravidian speakers from South India) were used as
proxies for the parental populations (Fig. S7). We then applied
wavelet-transform analysis to the StepPCO signal and used the
wavelet transform coefficients to infer time since admixture (20).
Briefly, this wavelet transform represents the admixture signal as
the sum of simple waves, each characterized by its frequency
(width) and position within the signal. The dominant frequency
present in the signal is an indirect measure of an average width
of the admixture blocks, and from this, the time of admixture is
estimated by comparing this observed dominant frequency to
that obtained for simulated data generated using the admixture
rate observed in the empirical data (20). The spectral analysis of
the StepPCO signal revealed that the estimated average dominant
frequency for the Australians was 3.9, which corresponds to
an abundance of high-frequency wavelets (that is, narrow ancestry
blocks). Based on simulations, this estimate corresponds
to an admixture time of 141 generations ago. Assuming a generation
time of 30 y (42), our results indicate that the gene flow
from India into Australia occurred around 4,230 y ago, consistent
with a previous estimate based on a small number of Y-STR
(short tandem repeats on the Y-chromosome) loci (14).
Interestingly, at around this time, several changes take place in
the archaeological record of Australia. There is a sudden change
in stone tool technologies, with microliths appearing for the first
time (43), and people start processing plants differently (14, 44).
It has been a matter of controversy as to whether these changes
occurred in situ (45) or reflect contact with people from outside
Australia or some combination of both factors. However, the
dingo also first appears in the fossil record at this time and must
have come from outside Australia (46). Although dingo mtDNA
appears to have a SE Asian origin (47), morphologically, the
dingo most closely resembles Indian dogs (46). The fact that we
detect a substantial inflow of genes from India into Australia at
about this same time does suggest that all of these changes in
Australia may be related to this migration.
12# fjnj
这种方法看来是可靠的,而且里面说这和以前Y的结果一致。可是我以前从来没有看过Y类似的分析。
13# wolfgang
Y似乎是没有,但是mtDNA有的
G Horvat (see comments) points me to Kumar 2009 (so far unchallenged at PhyloTree)  for a shared mitochondrial lineage between Australia and India, known as M42. This haplogroup has the following structure (each → indicates a coding region mutation according to PhyloTree, Kumar originally listed a few more):

M
→ M42'74
→ M42
→→→→ M42a (Australian Aborigines)
→ M42b (India)
→→ M74 (South China, Vietnam, India)
This allows for a potential mtDNA backing of this purported connection, however it is a very small lineage and Kumar claimed that M42 coalesced long ago, in the context of the first colonization of Asia and Australasia by Homo sapiens:

The divergence of the Indian and Australian M42 coding-region sequences suggests an early colonization of Australia, ~60 to 50 kyBP, quite in agreement with archaeological evidences.

Yet the relatively long stem leading to M42a does allow for a later time-frame of arrival to Australia. Neolithic anyhow looks still most unlikely to me.
14# 198401
这里M42a和M42b虽然支持澳洲和印度的联系,却是支持很久远的分离的。
15# wolfgang

是的。
如果来自4000年前的南印度,恰恰对应2000BC的印度河谷农民及南岛人的扩张。
澳大利亚土著的采集经济似乎难以理解。

对比组中没有中南半岛、东南亚岛屿(印度化地区),而且南部印度人过多。
16# 198401 开始也挺疑惑,比较好的解释也许是这些迁移的印度人本身也不会农业或者没受农业经济的影响,而是狩猎采集经济模式。
旧的文献中的ASI现已分成三个成份:Onge/Greater Andeman (Fig.3B中的黄色); New Geinua (Fig.3B中的黑色); Dravidian speakers (Fig.3B中的桔色).  桔色成分恐非真正的“印度土著”。
fjnj 发表于 2013-1-17 23:47
当年莱希博士一战成名的“ANI”与"ASI"实际上也是两种严重混血成分,这个只要一个简单的admix测试分析就可以知道,可知当年那个时代对常染成分的测试与分析方法是多么的简陋。 不过我们现在不能因此而苛求这位长相可爱的莱希,毕竟东亚人很多年后才知道原来咱们一个民族内部也可以分出南北两种不同的成分呢,而且记忆中似乎还是歪果仁率先发现的呢,呜呜呜

如果仔细观察一下K=6的admix结果,就会发现许多很有趣的信息:
oase-田园洞-南印度-墨西哥-smith2017.jpg
2017-9-23 16:16

Unetice EBA-乌克兰-南印度绿色.jpg
2017-9-23 16:16


K6-南亚绿色-澳洲成分-EN伊朗-Punjab-smith2017.jpg
2017-9-23 16:16


可以明显看到,南亚绿色(基本可以理解为一种真正的ASE)是一种分布非常广泛的成分,也是一种非常古老的成分,甚至在田园洞时期就已经遍布欧亚大陆了。从某种角度说,ASE与“AA(aboriginal australian澳美成分)”,相比现在东亚欧的另外两大主频成分E.A.与S.E.A.,更接近protoE.E.成分。
不仅在新石器早期的伊朗农人身上可以看到这种成分相当高频,在青铜早期Unetice古人与现代乌克兰人也可以明显看到这种南亚绿色,说明这种ASE成分在proto印欧人形成之时就已经是其中的固有成分之一了(目前在欧洲人身上普遍观察到的EE成分,其中一部分无疑与此有关,当然,更早期的旧石器时期的古欧洲人还有不菲“AA澳美成分”,都是欧洲人身上EE成分的来源之一)。ASE不仅是印欧语人群的底层成分之一,同时也是闪米特语人群以及超过一半的突厥语人群的底层之一。
物格而后知至,知至而后意诚,意诚而后心正,心正而后身修,身修而后家齐,家齐而后国治,国治而后天下平...
...ASE不仅是印欧语人群的底层成分之一,同时也是闪米特语人群以及超过一半的突厥语人群的底层之一。
imvivi001 发表于 2017-9-23 16:16
更准确的说,是“ASE不仅是印欧语人群的底层成分之一,同时也是闪米特语人群、超过一半的突厥语人群的重要底层之一。对其他东亚人群特别是南方民族如南汉傣苗壮台湾土著而言,应该也是其重要底层之一,不过一般表现为与EA混合的形式存在(应该是在旧石器时期就已经混合,之后大部分独立演化成为现在的SEA成分)。”
物格而后知至,知至而后意诚,意诚而后心正,心正而后身修,身修而后家齐,家齐而后国治,国治而后天下平...
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