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First modern Britons had 'dark to black' skin
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[QUOTE]Originally posted by Ish Gebor: [QB] [QUOTE]Originally posted by Dinkum: [qb] Haplogroup R1A originated in Eurasia. There is no definite proof where it originated, BUT IT LIKELY ORIGINATED IN IRAN or Central Asia: [IMG]http://zakhor-online.com/wp-content/uploads/2017/12/Origins-of-Haplogroup-R1a-1.jpg[/IMG] [/qb][/QUOTE]. [QUOTE] An ancient human back migration from Asia to Africa had already been proposed by Altheide and Hammer (1997) and Hammer et al. (1998, 2001), on the basis of nested cladistic analysis of Y-chromosome data. They suggested that the presence of YAP+ chromosomes in Africa was due to such an event, but this has recently been questioned by Underhill et al. (2001b) and Underhill and Roseman (2001), primarily on the basis of the Asian-specific YAP+ subclade that neutralizes the previous phylogenetic inferences. Thus, the only evidence of a migration from Asia to sub-Saharan Africa that is fully supported by Y-chromosome data relies, at least for the moment, on the finding of haplogroup IX chromosomes in Cameroon. Group IX Chromosomes in Sub-Saharan Africa: An Asian Origin? How can the presence of Group IX chromosomes at considerable frequency in Cameroon be explained? A priori, we can envision three possibilities. [b]First, group IX chromosomes in Cameroon are due to rather recent male gene flow from Europe or the Near East. Second, the entire M9 superclade (haplogroups VII–X) has an African origin. Third, group IX chromosomes in Cameroon represent a footprint of a male back migration from Asia to Africa. [/b] The first scenario seems to be very unlikely, because only derived haplotypes, carrying the M269 or M17/SRY10831 mutations, have been detected in western Eurasia. The second hypothesis, an African origin of the M9 superclade that includes haplotype 117, would imply a subsequent impressive extinction of derivative lineages in sub-Saharan Africa, since no other haplotypes carrying the M9 mutation (haplogroups VII–X) have been observed in this region (the only exception being represented by a few haplotype 109 chromosomes found in the Fulbe from Cameroon). The last scenario, that of a back migration from Asia to Africa, currently appears to be by far the most plausible. This is because most of the M9 haplotypes (the majority of group VII and VIII lineages, as well as some group IX and X lineages reported by Underhill et al. [2000]) have been observed only in Asia. Moreover, this possibility appears to be further supported by the recent finding of the UTY2+/M173− intermediate haplotype (Karafet et al. 2001) in central and northeastern Asia (the UTY2 marker in the study by Karafet et al. [2001] corresponds to M207 in the present study). [/QUOTE]—Fulvio Crucian et al. A Back Migration from Asia to Sub-Saharan Africa Is Supported by High-Resolution Analysis of Human Y-Chromosome Haplotypes However in the 2011 paper they found chromosomes to be matching, which lacked presence in prior studies, thus the phylogenetic needed a reevaluation. And the painful conclusions can be read, in more recent papers published by Fulvio Crucian et al. [QUOTE] In conclusion, we present here a Y chromosome phylogenetic tree deeply revised in its root and earliest branches.[b] Our data do not uphold previous models of Y chromosomal emergence 15, 16 and demand a reevaluation of some fundamental ideas concerning the early history of the human genetic diversity we find today. [/b] 38–40 Our phylogeny shows a root in central-northwest Africa. Although this point requires further attention, we think that it offers a new prospect from which to view the initial development of our species in Africa. [/QUOTE]—Fulvio Cruciani et al. A Revised Root for the Human Y Chromosomal Phylogenetic Tree: The Origin of Patrilineal Diversity in Africa [IMG]https://s-media-cache-ak0.pinimg.com/564x/f8/61/6e/f8616e0d92e5387c154173e46df72466.jpg[/IMG] [/QB][/QUOTE]
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