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Science Review: 从亚洲遗址的角度看现代人的起源

http://science.sciencemag.org/content/358/6368/eaai9067

Review       Science  08 Dec 2017:        

On the origin of modern humans: Asian perspectives

The peopling of Asia

In recent years, there has been increasing focus on the paleoanthropology of Asia, particularly the migration patterns of early modern humans as they spread out of Africa. Bae et al. review the current state of the Late Pleistocene Asian human evolutionary record from archaeology, hominin paleontology, geochronology, genetics, and paleoclimatology. They evaluate single versus multiple dispersal models and southern versus the northern dispersal routes across the Asian continent. They also review behavioral and environmental variability and how these may have affected modern human dispersals and interactions with indigenous populations.

Structured
Abstract
BACKGROUND

The earliest fossils of Homo sapiens are located in Africa and dated to the late Middle Pleistocene. At some point later, modern humans dispersed into Asia and reached the far-away locales of Europe, Australia, and eventually the Americas. Given that Neandertals, Denisovans, mid-Pleistocene Homo, and H. floresiensis were present in Asia before the appearance of modern humans, the timing and nature of the spread of modern humans across Eurasia continue to be subjects of intense debate. For instance, did modern humans replace the indigenous populations when moving into new regions? Alternatively, did population contact and interbreeding occur regularly? In terms of behavior, did technological innovations and symbolism facilitate dispersals of modern humans? For example, it is often assumed that only modern humans were capable of using watercraft and navigating to distant locations such as Australia and the Japanese archipelago—destinations that would not have been visible to the naked eye from the departure points, even during glacial stages when sea levels would have been much lower. Moreover, what role did major climatic fluctuations and environmental events (e.g., the Toba volcanic super-eruption) play in the dispersal of modern humans across Asia? Did extirpations of groups occur regularly, and did extinctions of populations take place? Questions such as these are paramount in understanding hominin evolution and Late Pleistocene Asian paleoanthropology.

ADVANCES
An increasing number of multidisciplinary field and laboratory projects focused on archaeological sites and fossil localities from different areas of Asia are producing important findings, allowing researchers to address key evolutionary questions that have long perplexed the field. For instance, technological advances have increased our ability to successfully collect ancient DNA from hominin fossils, providing proof that interbreeding occurred on a somewhat regular basis. New finds of H. sapiens fossils, with increasingly secure dating associations, are emerging in different areas of Asia, some seemingly from the first half of the Late Pleistocene. Cultural variability discerned from archaeological studies indicates that modern human behaviors did not simply spread across Asia in a time-transgressive pattern. This regional variation, which is particularly distinct in Southeast Asia, could be related at least in part to environmental and ecological variation (e.g., Palearctic versus Oriental biogeographic zones).

OUTLOOK
Recent findings from archaeology, hominin paleontology, geochronology, and genetics indicate that the strict “out of Africa” model, which posits that there was only a single dispersal into Eurasia at ~60,000 years ago, is in need of revision. In particular, a multiple-dispersal model, perhaps beginning at the advent of the Late Pleistocene, needs to be examined more closely. An increasingly robust record from Late Pleistocene Asian paleoanthropology is helping to build and establish new views about the origin and dispersal of modern humans.
      
               
        Map of sites with ages and postulated early and later pathways associated with modern humans dispersing across Asia during the Late Pleistocene.Regions of assumed genetic admixture are also shown. ka, thousand years ago.
   
Abstract
The traditional “out of Africa” model, which posits a dispersal of modern Homo sapiens across Eurasia as a single wave at ~60,000 years ago and the subsequent replacement of all indigenous populations, is in need of revision. Recent discoveries from archaeology, hominin paleontology, geochronology, genetics, and paleoenvironmental studies have contributed to a better understanding of the Late Pleistocene record in Asia. Important findings highlighted here include growing evidence for multiple dispersals predating 60,000 years ago in regions such as southern and eastern Asia. Modern humans moving into Asia met Neandertals, Denisovans, mid-Pleistocene Homo, and possibly H. floresiensis, with some degree of interbreeding occurring. These early human dispersals, which left at least some genetic traces in modern populations, indicate that later replacements were not wholesale.
不错的文章,从图中可以看出现代人在4.5万年前左右发生了一次在“旧世界”的大范围扩张,这与C、F、D支系在5到4.5万年前发生的剧烈分化过程也是相吻合的。
此外,文章提到了更早一批出非洲人群的影响。除了丹尼索瓦人和尼安德特人,可能还包括十万年前左右走出非洲的一批现代人。虽然这批现代人的Y染与线粒体标记没有传递下来,但他们的常染成分还是有迹可循的,比如在澳洲土著和巴布亚人群。至于这一人群对其他地区的影响,希望今后能出现更多这方面的信息。
C-M130交流群:542136235
http://news.rti.org.tw/news/detail/?recordId=383895

人類歷史新發現 走出非洲說可望改寫   2017-12-08 15:47

科學文獻評論7日指出,現代人源於6萬年前從非洲走出的單一遷徙說法,不能再被視為是人類精確的歷史了。

美國「科學雜誌」(Science)刊登的研究結果指出,12萬年前就開始走出非洲的多次遷徙,才造就現今的人類。

DNA分析的進步和其他化石鑑定技術,特別是亞洲地區的相關發現,有助改寫我們對人類起源的認知。

研究報告指出,過去10年的「大批新發現」,顯示現代人或智人比先前以為的還要早就抵達亞洲大陸各地。

法新社報導,中國大陸南部和中部多處已經發現智人遺骸,年代可追溯至7萬到12萬年前之間。

其他化石發現顯示,現代人早在6萬年前就抵達東南亞和澳洲。

德國馬克斯普朗克人類歷史科學研究所(Max Planck Institute for the Science of Human History)研究人員佩塔利亞(Michael Petraglia)說:「6萬年前最初從非洲散布出去的可能是小群覓食者,至少這些早期離開非洲的覓食者在現代人身上留下低程度的遺傳痕跡。」

佩塔利亞表示:「後來大規模的『走出非洲』(Out of Africa)事件最有可能發生在約6萬年前或之後。」

報告指出,最近的研究已經證實6萬年前的這波大規模遷徙事件,「造就當今非洲人以外人類的大量基因組成」。

這些早期從非洲出走的人類在歐亞大陸許多地方與其他人種交配,包括尼安德塔人(Neanderthal)、丹尼索瓦人(Denisovan),和一種目前尚未辨識出的前現代人族。

科學家評估,非洲人種外的現代人有1%到4%的DNA來自尼安德塔人,多達5%的DNA可能來自丹尼索瓦人。

研究指出:「顯然現代人、尼安德塔人、丹尼索瓦人,以及可能的其他人族群體可能在亞洲有時空上的交疊,當然也會有許多互動的情況。」
看看更多的古DNA证据吧,这种总结性的文章并不起什么作用
Y区有个一模一样的,管理员为啥不合并一下涅?
黎巴嫩人的祖先,腓尼基人结合古埃及象形文字(约5千年前发明)和苏美尔楔形文字(约5千年前发明),发明了腓尼基字母(约3.2千年前),由此演化出来希伯来字母,阿拉伯字母,希腊字母,拉丁字母,德语,法语,英语,印度语等等。
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