2014年1月5日 星期日

Re-Examining the "Out of Africa" Theory and the Origin of Europeoids (Caucasoids) in Light of DNA Genealogy



人類起源:美國科學院正式推翻「走出非洲」論



▲現代人的起源地是非洲嗎?(圖/達志影像)
國際中心/綜合報導
現代人的起源問題一直是一個備受爭論的話題,現今「走出非洲」理論是多數人普遍接受的主流理論。2012年5月美國DNA譜系科學院Anatole A. Klyosov重新審視了「走出非洲」論和歐羅巴人種的起源,認為人類並非起源於非洲,並使用“Walk through Y”項目的數據證明了這一觀點。研究結果發表在科研出版社英文期刊《Advances in Anthropology》(人類學進展)上(點擊閱讀原文)。
在過去的二十年裡,「走出非洲」論已經人盡皆知,但它卻從未被直接證明過。然而,對於許多專家來說,這一理論仍然具有著令人信服的吸引力。這一理論 主要基於這樣一個前提:最古老的人群顯示出最大的多樣性,而非洲人是多樣性最大的人群。其實這並不是一個強有力的論點,因為不同DNA的混合也會導致高的 多樣性。
作者從解剖學角度研究了現代人類的起源,根據人類遺傳學和DNA系統發育的分類發展,針對男性Y染色體單倍型,提出了一個歐羅巴人種(白種人又稱歐亞人種或高加索人種)起源的時間表,確定其在今天已知的所有單倍群中的位置,提供證據重新審視「走出非洲」論的正確性。
作者在非洲人Y染色體單倍型中發現了一個重大的多樣性,是幾個非常遙遠的血統的混合結果,而且其中一些不一定是來自非洲人,證明歐羅巴人種不包含「非洲」單核苷酸多態性(單倍型類群A或B)。這些重要的發現削弱了眾所周知的「走出非洲」的理論。
17個主要單倍型類群中46個進化亞枝的7556種單倍型,按照它們祖先的單倍型和與共同祖先的時間間隔,設計了一個時間平衡單倍型類群樹,發現非 洲單倍型類群A起源於距今132000±12000年前,來自於所​​有的其他有著單獨共同祖先的單倍群,我們稱其為β單倍群,起源於 64000±6000年前。一個單倍群A和β單倍群下游的共同祖先,創造了α單倍群,起源於160000±12000年前。
α單倍群和β單倍群的起源是未知的,但是最有可能的是它們是一個巨大的三角關係,從西方歐洲中部延伸通過俄羅斯平原東部到黎凡特南部。單倍群B是β單倍群可能是在距今46000年遷移到非洲。
研究證明,歐羅巴人種單倍群並非起源於「非洲」的單倍型類群A或B,事實支持歐羅巴人種以及所有非非洲人的單倍型類群,並未攜帶單核苷酸多態性 M91、P97、M31、P82、M23、M114、P262 、M32、M59、P289、P291、P102、M13、M171、M118 (單倍型類群A及其進化亞枝單核苷酸多態性)或M60 、M181、P90(單倍型類群B),這是最近在“Walk through Y”FTDNA項目中,幾百個來自各種單倍群的人顯示的結果。
2013年11月澳洲墨爾本考爾菲德南部國際岩石藝術聯合會(IFRAO) Robert G. Bednarik也在科研出版社英文期刊《Advances in Anthropology》(人類學進展)發表的一篇文章中,從多個角度分析反駁了「走出非洲」理論,認為「走出非洲」理論是一個騙局(點擊閱讀原文)。(新聞來源:科研出版社/爾灣閱讀)

Re-Examining the "Out of Africa" Theory and the Origin of Europeoids (Caucasoids) in Light of DNA Genealogy
PDF (Size:750KB) PP. 80-86   DOI: 10.4236/aa.2012.22009
Author(s)
Anatole A. Klyosov, Igor L. Rozhanskii
Seven thousand five hundred fifty-six (7556) haplotypes of 46 subclades in 17 major haplogroups were considered in terms of their base (ancestral) haplotypes and timespans to their common ancestors, for the purposes of designing of time-balanced haplogroup tree. It was found that African haplogroup A (originated 132,000 ± 12,000 years before present) is very remote time-wise from all other haplogroups, which have a separate common ancestor, named β-haplogroup, and originated 64,000 ± 6000 ybp. It includes a family of Europeoid (Caucasoid) haplogroups from F through T that originated 58,000 ± 5000 ybp. A downstream common ancestor for haplogroup A and β-haplogroup, coined the α-haplogroup emerged 160,000 ± 12,000 ybp. A territorial origin of haplogroups α- and β-remains unknown; however, the most likely origin for each of them is a vast triangle stretched from Central Europe in the west through the Russian Plain to the east and to Levant to the south. Haplogroup B is descended from β-haplogroup (and not from haplogroup A, from which it is very distant, and separated by as much as 123,000 years of “lat- eral” mutational evolution) likely migrated to Africa after 46,000 ybp. The finding that the Europeoid haplogroups did not descend from “African” haplogroups A or B is supported by the fact that bearers of the Europeoid haplogroups, as well as all non-African haplogroups do not carry either SNPs M91, P97, M31, P82, M23, M114, P262, M32, M59, P289, P291, P102, M13, M171, M118 (haplogroup A and its subclades SNPs) or M60, M181, P90 (haplogroup B), as it was shown recently in “Walk through Y” FTDNA Project (the reference is incorporated therein) on several hundred people from various haplogroups.


Haplogroup - Wikipedia, the free encyclopedia

en.wikipedia.org/wiki/Haplogroup
In molecular evolution, a haplogroup (from the Greek: ἁπλούς, haploûs, "onefold, single, simple") is a group of similar haplotypes that share a common ancestor ...

Human mitochondrial DNA

In human genetics, a human mitochondrial DNA haplogroup ...

Haplogroup J-P209

Haplogroup J-P209 is believed to have arisen roughly 31,700 ...

Human Y-chromosome DNA

In human genetics, a human Y-chromosome DNA haplogroup ...

Haplogroup L-M20

Haplogroup L-M20 is associated with South Asia. It has also ...

Haplogroup I-M170

In human genetics, Haplogroup I-M170 is a Y-chromosome DNA ...

Haplotype

A haplotype (from the Greek: ἁπλοῦς, haploûs, "onefold ...


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