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本帖最后由 Ryan 于 2015-10-16 17:24 编辑


http://www.nature.com/news/teeth ... t-of-africa-1.18566

Nature | News

Teeth from China reveal early human trek out of Africa

"Stunning" find shows that Homo sapiens reached Asia around 100,000 years ago.

Ewen Callaway
14 October 2015

Teeth from a cave in south China show that Homo sapiens reached China around 100,000 years ago — a time at which most researchers had assumed that our species had not trekked far beyond Africa.

Nature PodcastMaría Martinón-Torres explains how a set of ancient teeth challenges ideas of early human migration. Go to full podcast

“This is stunning, it’s major league,” says Michael Petraglia, an archaeologist at the University of Oxford, UK who was not involved in the research. “It’s one of the most important finds coming out of Asia in the last decade.”
Limestone caves pockmark Daoxian County in Hunan Province, China. Recent excavations of a cave system there extending over 3 square kilometres discovered 47 human teeth, as well as the remains of hyenas, extinct giant pandas and dozens of other animal species. The researchers found no stone tools; it is likely that humans never lived in the cave and their remains were instead hauled in by predators.

The teeth are unquestionably those of H. sapiens, says María Martinón-Torres, a palaeoanthropologist at University College London who co-led the study with colleagues Wu Liu and Xie-jie Wu at the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing. Their small size, thin roots and flat crowns are typical for anatomically modern humans — H. sapiens — and the overall shape of the teeth is barely distinguishable from those of both ancient and present-day humans. The team report their results in Nature today1.

Determining the age of the teeth proved tricky. They contained no radioactive carbon (which has almost vanished after 50,000 years). So the team dated various calcite deposits in the cave and used the assortment of animal remains to deduce that the human teeth were probably between 80,000 and 120,000 years old.

Early trekkersThose ages buck the conventional wisdom that H. sapiens from Africa began colonizing the world only around 50,000–60,000 years ago, says Martinón-Torres. Older traces of modern humans have been seen outside Africa, such as the roughly 100,000-year-old remains from the Skhul and Qafzeh Caves in Israel. But many researchers had argued that those remains were only evidence of unsuccessful efforts at wider migration.
Researchers María Martinón-Torres, José María Bermúdez de Castro, Liu Wu and Wu Xiujie in the cave.

“This demonstrates it was not a failed dispersal,” says Petraglia, who has long argued for an early expansion of modern humans through Asia on a southerly route. “This is a rock-solid case for having early humans — definitely Homo sapiens — at an early date in eastern Asia.” Chris Stringer, a palaeoanthropologist at the Natural History Museum in London who had argued that remains from Skhul and Qafzeh signified unsuccesful migrations, says that he is now swayed by the Daoxian teeth.

Without DNA from the teeth, it is impossible to determine the relationship between the Daoxian people and other humans, including present-day Asians. But Jean-Jacques Hublin, a palaeoanthropologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, thinks that later waves of humans replaced them. Other genetic evidence sugests that present-day East Asians descend from humans who interbred with Neanderthals in western Asia some 55,000–60,000 years ago, Hublin notes.

It is also not clear whymodern humans would have reached East Asia so long before they reached Europe, where the earliest remains are about 45,000 years old. Martinón-Torres suggests that humans could not gain a foothold in Europe until Neanderthals there were teetering on extinction. The frigid climate of Ice Age Europe may have erected another barrier to people adapted to Africa, says Petraglia.

Although Hublin says there is a good case that the Daoxian teeth are older than 80,000 years, he notes that several of the teeth have visible cavities, a feature uncommon in human teeth older than 50,000 years. “It could be that early modern humans had a peculiar diet in tropical Asia,” he says. “But I am pretty sure that this observation will raise some eyebrows." Martinon-Torres says her team plans to look more closely at the cavities and the diet of the Daoxian humans by examining patterns of tooth wear.

Southern China is filled with similar caves that may colour in more details of humans’ early exploits, such as the tools they made. “This is just the tip of the iceberg,” Petraglia says. “There’s a lot more work that needs to be done."

本帖最后由 Ryan 于 2015-10-16 18:56 编辑

Nature 评论文章:

http://www.nature.com/nature/jou ... ll/nature15640.html

Nature | News & Views

Palaeoanthropology: Homo sapiens in China 80,000 years ago
Robin Dennell

Nature (2015)  doi:10.1038/nature15640 Published online 14 October 2015

A discovery in southern China of human teeth dated to more than 80,000 years old indicates that Homo sapiens was present in the region considerably earlier than had previously been suspected.

Debate over when our species, Homo sapiens, first dispersed from Africa across southern Asia is hindered by a lack of relevant fossil evidence between the eastern Mediterranean and southeast Asia. Exciting new material is presented in a paper online in Nature, in which Liu et al.1 describe a collection of H. sapiens teeth from a cave in southern China's Hunan province. The age and morphology of the teeth suggest that modern humans reached southern China long before they had arrived in northern China or in Europe.

Most researchers agree that our species first appeared in East Africa around 190,000 to 160,000 years ago, and then dispersed into the eastern Mediterranean around 100,000 to 60,000 years ago, after which it was replaced by Neanderthals. Following this apparent 'failed dispersal'2, one suggested scenario is that H. sapiens did not progress eastwards until around 60,000 years ago — a date based on the estimated divergence time of genetic lineages in South Asian people3 and the probable arrival date of humans in Australia4. This picture is supported by apparent similarities between small stone tools known as microliths from South Africa dating to around 60,000 years ago and ones from South Asia that are between 30,000 and 36,000 years old3, 5. These similarities have been interpreted as showing a direct link between the earliest modern humans in South Asia and their probable African ancestors5, although the similarities now seem less robust than was first argued6. A contrasting scenario is that H. sapiens first dispersed eastwards (probably by way of the Arabian Peninsula) during the last interglacial period, and entered South Asia well before 60,000 years ago, and perhaps before the volcanic super-eruption that occurred 74,000 years ago at present-day Lake Toba in Indonesia7, 8, 9.

One place where these hypotheses can be tested is in southern China, which is dotted with karst caves that are rich fossil sources. But descriptions of this material have so far been ambiguous because of doubts over the stratigraphic context of skeletal specimens, their dating and/or their identification. Some finds were made by villagers while digging for fertilizer, which obscured the stratigraphic context of the fossils; in other cases, fossil teeth are too worn for identification purposes, or the association between a dated flowstone deposit and a skeletal specimen is unclear10. At Zhiren Cave in southern China, for example, a mandible (lower jawbone) attributed to H. sapiens was found in a geological sequence dated by five flowstones ranging from 110,000 to 55,000 years old11, so the specimen may be younger than the published age of 110,000 years12; it has also been suggested that the mandible is from a late Homo erectus individual13.

Liu and colleagues' discoveries at Fuyan Cave are especially welcome because they seem to lack these usual problems surrounding context, dating and identification. A flowstone (layer 1) covers the entire cave floor, so the underlying material clearly has to be older; a stalagmite on this flowstone was dated to a minimum age of 80,100 years old (± 1,200 years). The underlying layer 2 is a thin, sandy clay around 20–50 centimetres thick, in which the authors identify numerous mammalian fossils from 38 extant species and 5 extinct large mammals. This fauna is identified as being from the Upper Pleistocene period (125,000 to 10,000 years ago), so the human teeth, which were found in layer 2 in part of the cave, are estimated to be between 80,000 and 120,000 years old.

The teeth are well preserved and show detailed cusp morphology. All 47 are unequivocally attributed to H. sapiens. The authors describe them as generally smaller than other African and Asian specimens from the Upper Pleistocene, and closer in size to those of Upper Pleistocene Europeans and contemporary modern humans. The M1 molar teeth in the sample are different in shape from the rhomboidal contours displayed by Neanderthals or the elongated teeth seen in Asian H. erectus fossils. Instead, the relative cusp and occlusal polygon areas of the M1 molars are almost identical to those of modern Chinese populations. They also seem less primitive than northern Chinese specimens such as those discovered at the Xujiayao site14.

This discovery has several implications. The finding that H. sapiens first appeared in southern China between 120,000 and 80,000 years ago indicates that our species dispersed across southern Asia well before 60,000 years ago (Fig. 1). Furthermore, the fact that the teeth resemble those of Upper Pleistocene Europeans and modern humans implies that the population they came from were immigrants and not the outcome of local evolution from H. erectus. To place these finds in their continental context, the Fuyan teeth indicate that modern humans were present in southern China 30,000 to 60,000 years earlier than in the eastern Mediterranean and Europe. This is not surprising, perhaps. H. sapiens originated in or near the tropics, so it makes sense that the species' initial dispersal was eastwards rather than northwards, where winter temperatures rapidly fell below freezing. As Liu and colleagues point out, the finds also imply that modern humans were in southern China long before there is evidence for them in northern China and Europe. In the case of northern China, the earliest evidence is from Tianyuan Cave near Beijing, dated to around 40,000 years ago15; in Europe, evidence appears around 45,000 to 40,000 years ago16. Here, the authors suggest, the presence of Neanderthals may have delayed the arrival of modern humans. However, the predominantly colder winter conditions of the enormous landmass between Europe and northern China may better explain the earlier colonization of southern zones.

Figure 1: Human dispersal.
Liu and colleagues' discovery1 of modern-human teeth at Fuyan Cave in southern China implies that Homo sapiens dispersed towards the east and south from Arabia or the eastern Mediterranean between 120,000 and 80,000 years ago, considerably earlier than the species is known to have first arrived in Europe and northern China, around 40,000 years ago. The delayed dispersal to these northern regions may be explained by the well-established resident Neanderthal populations in Europe and Siberia, and the harsh, sub-zero winter conditions.

Excavation of other caves in the region will undoubtedly add to the findings from Fuyan. What is especially needed now is archaeological evidence (sadly lacking in Fuyan Cave) to indicate whether the initial dispersal of our species was caused or facilitated by cognitive developments (such as symbolism or complex exchange systems), or was simply an example of opportunistic range extension. More revelations about our species' history can surely be expected from southern China.
来自 王传超博士的评论:


知识分子 2015-10-15 08:28



10月15日上线的Nature文章中,中科院古脊椎动物与古人类研究所研究员刘武、吴秀杰,以及西班牙的牙齿人类学专家María Martinón-Torres等发表关于道县福岩洞古人类牙齿的研究报告,认为解剖学意义上的现代人,至少在8万年前就已在中国南方出现。
















还有一些中间学说,比如中科院古脊椎动物与古人类研究所吴新智先生提出中国人类进化的“多地区起源附带杂交”说,既承认现代人的多地区起源,又认为不同大陆上的古人类有过基因交流,“前者为主要趋势, 后者与时俱增”。吴先生该假说主要依据是中国古人类化石在整体连续的基础上又反映出的可能来自西方基因流影响的特征,例如山顶洞 102号头骨眼眶外侧骨柱前外侧面比较朝向外侧、南京头骨高耸的鼻梁等等。





2010年,中科院古脊椎动物与古人类研究所对广西崇左江州区木榄山智人洞的11万年前古人类下颌骨化石进行研究,发现其已经出现一系列现代人的衍生特征,如明显的颏三角、突起的联合结节、明显的颏窝、中等发育的侧突起、近乎垂直的下颌联合部、明显的下颌联合断面曲度等,同时,还保留有粗壮的下颌体以及较明显的下横圆枕等相对原始的特征。研究者因此认为,智人洞古人类属于正在形成中的早期现代人,处于早期智人向晚期智人演化的过渡阶段。不过,对于如何通过形态特征判定具体的人类化石是否属于早期现代人,目前在古人类学界还没有统一标准,有时甚至存在争议。英国艾克塞特大学Robin Dennell教授就在Nature撰文,对智人洞下颌特征及被确定为早期现代人的分类地位提出不同意见。

2014年,美国夏威夷大学的Christopher Bae、广西民族博物馆王頠等分析研究了广西陆那洞中的两颗距今7万~12.7万年的牙齿化石,也是主要基于牙齿的齿冠长度和宽度,他们推测,至少有一颗应属于现代人。







2010年,德国马普所的Svante Pääbo与哈佛大学医学院的David Reich研究组,对尼人全基因组进行测序分析时就得到了不同的结果,他们在非洲现代人中还是没有发现任何尼人的遗传成分,但是在非洲之外的现代人中都发现有1%~4%的尼人基因组成分。由此看来,现代人与尼人之间的基因交流可能发生过,但是非常有限,对现代人的贡献很少。



本帖最后由 Ryan 于 2015-10-18 20:28 编辑


摘要:亚洲南部非常缺乏晚更新世早期的人类化石遗骸。这一地区极少发现测年准确保存完好且能够毫无争议地归为Homo sapiens的早于~45,000年的人类化石。在本文中,我们发布了新近发掘的中国南部道县福岩洞的人类牙齿化石证据。这一遗址出土了47颗年代早于8万年的人类牙齿,且其年代上限可达12万年。形态学和测量学的评估显示,这些牙齿可以毫无争议地归类为 H. sapiens。道县人类牙齿的形态比所有其他的AMH(Anatomically Modern Humans) 都更为进步, 包括晚更新世中期至早期的样本甚至现代人。我们的研究显示,具有完全形态的现代人类在东亚出现的时间比黎凡特地区和欧洲早3万到7万年。我们的数据填补了H. sapiens出现在亚洲南部这一过程中的年代和地理上的空白。道县人类牙齿的发现也支持以下假说,即在相同的时段,居住在中国南部的人类比中部和北部的人类更为进步。这一证据对于理解早期现代人类扩散的路径非常重要。最后,我们的研究结果也有助于理解现代人类较晚进入欧洲的原因。有研究认为与现代人类的竞争是尼安德特人消亡的原因之一。值得注意的是,尽管有现代人类于8万年以前到达东亚的证据,目前还没有现代人类早于4.5万年进入欧洲的证据。这种状态提示尼安德特人可能是现代人进入欧洲的一个生态学障碍,只有在尼人开始消亡之后,现代人才开始在欧洲扩散。


上限:nine samples of speleothemfragments from layers 2 to 3 (FYS-1 to FYS-9) at regions I and II. 。遗物层之下的堆积层的碎屑物。556 kyr BP to 120.7 kyr BP。

下限:two subsamples (FYS-S1 to FYS-S2) from a small stalagmite that grew
on the top of layer 1.  layer 1(遗物层)之上的石笋。80.16+/-1.2 kyrBP and 79.56+/-2.8 kyrBP。
考虑到其他动物化石的生活年代,人类牙齿的年代断定为 距今12-8万年。

This is pre-Toba, so it likely has little relationship to present east asian populations.  The talk of an east asia orgin of modern human is just ridiculous.
本帖最后由 xavierxh 于 2015-10-26 15:01 编辑




   刘武支持多地起源说。他和中国科学院古脊椎动物与古人类研究所研究员吴秀杰带领的研究团队在湖南发现了前述化石。2011年-2013年3年间,他们在湖南省永州市道县乐福堂乡的一个名为“福岩洞”的洞穴中发掘出47颗人类牙齿化石,以及大量的野生动物化石,如剑齿象、貘、猕猴、叶猴、长臂猿、梅花鹿等的化石.    ...
Ryan 发表于 2015-10-15 13:40
本帖最后由 隆攀gdzq 于 2015-10-17 09:54 编辑

2015-10-17 09:54

本帖最后由 baiyueren 于 2015-10-18 10:21 编辑

NRY: O2a1c1a1a1a1a1a1-002611,F11,F17,F856,F1495(源自粤西云浮)
百越人的人类学文集 http://blog.sina.com.cn/baiyueren
与M168对应的母系类型应是L3,与L2分叉于11.5万年前,非洲有L3的a、b、d、e、f、i、h、x多个分支,与M、N的分叉年代大约在7万年前。如果L3在11万年前就跟M168迁徙入东亚南部,按理就不应该在非洲出现诞生于7万年前的 ...
隆攀gdzq 发表于 2015-10-17 09:19
我觉得  隆攀的分析很有道理。不过,从中东返回非洲的迁徙一直存在。所以,带回去多少母系并不好说。
本帖最后由 Ryan 于 2015-10-18 22:22 编辑


第一种可能:    结合Behar2012和Karmin2015对全世界Y-DNA和mtDNA的分化的计算,现代人类在10万年已经走出非洲是很有可能的。Y染色体单倍群DT在10万年前从 A/B上分化出来,到7.3万年前 DE与CT分化。距今5万年绝大部分现存父系才开始大扩散。从现有的单倍群分布来看,在距今5万年以前,现存Eurasian的父系祖先应生活在中东至南亚西北部一带。

也就是说,在10万年至7.3万年之前,很可能存在很多 DT*(xDE, CT)这样的父系,并且扩散到环印度洋区域甚至内陆地区。只不过由于 多巴火山的喷发,他们都灭绝了。只剩下 DE'CT这一支男性存活。之后非洲之外的所有父系都是这一个支系的男性的后裔。

丹尼索瓦人至少存活到4万年。根据 Micheal Hammer和Prof. Li的观点,东亚早期智人很有可能都可以归类为丹尼索瓦人。丹尼索瓦人的分布范围可能包括南亚,东南亚及其岛屿地区,东亚和北亚。


本帖最后由 Ryan 于 2015-10-18 22:34 编辑

Early AMH dispersal. 修改自Behar et al. 2012和Karmin et al. 2015。 经 fjnj在 25#的提示,考虑了pre-Toba 的观点。
Early AMH dispersal.png
35# Ryan 传统上所说的早期智人是相当于东亚大约二十万至十万年的人类,五万年以后的具有现代人特征的叫晚期智人。根据特征往前往非洲推,十几二十万年早期的现代人祖先也应叫晚期智人,像尼安德特人及丹尼索瓦人才叫早期智人,其与现代人祖先分叉年代在四十万年以上,据说分叉年代尼人是四十万年、丹人是70万年,像曲江马坝人这种保留有猿人特征的应是丹尼索瓦人类,而福岩洞具有明显的现代人特征的就不会是丹尼索瓦人。
35# Ryan 传统上所说的早期智人是相当于东亚大约二十万至十万年的人类,五万年以后的具有现代人特征的叫晚期智人...像曲江马坝人这种保留有猿人特征的应是丹尼索瓦人类,而福岩洞具有明显的现代人特征的就不会是丹尼索瓦人。
隆攀gdzq 发表于 2015-10-19 07:27
本帖最后由 隆攀gdzq 于 2015-10-19 07:57 编辑

YFull Experimental YTree v3.16
BT   V187/PF1403 * M8968/PF207 * M42... 403 SNPsformed 126300 ybp, TMRCA 83800 ybpinfo
B  M8740 * M8872 * M8777... 30 SNPsformed 83800 ybp, TMRCA 73900 ybpinfo
CT  M5608/PF258 * V3858/PF970 * V2901/M5675/PF719... 316 SNPsformed 83800 ybp, TMRCA 68100 ybpinfo

2015-10-19 08:06

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